ES2822179T3 - Modeling a digital design of a dental prosthesis - Google Patents

Abstract

A method for modeling a digital design of a dental prosthesis (2464) for a patient, said dental prosthesis comprising a gingival part (2466) and a dental part comprising a set of dental prosthesis teeth (1930; 2430), where the method it comprises: - obtaining a 3D digital representation of the patient's gingiva (1925, 1928); - obtain virtual dental models corresponding to the teeth of the dental prosthesis (1930; 2430); - virtually arrange the virtual dental models (1930; 2430) in relation to the 3D digital representation of the patient's gingiva (1925; 1928); and - generating a virtual external gingival surface of the gingival part (2466) of the dental prosthesis (2464), - selecting the virtual dental models (1930; 2430) from a virtual library comprising a set of dental models (1930; 2430) for the lower jaw (1928) and a set of dental models (1930; 2430) for the upper jaw (1925), where the set of dental models for the lower jaw and the set of dental models for the upper jaw constitute a pair that fit together and are arranged in occlusion.

Description

DESCRIPTION

Modeling a digital design of a dental prosthesis

This invention relates generally to a method for modeling a digital design of a dental prosthesis. More particularly, the invention relates to a method for modeling the gingival part and / or the dental part of the dental prosthesis.

A document in the art is exemplified by EP 2621 397 A1.

A method is described for modeling a digital design of a dental prosthesis of a patient, said dental prosthesis comprising a gingival part and a dental part comprising a set of dental prosthesis teeth, where the method comprises:

- obtain a 3D digital representation of the patient's gingiva;

- obtain virtual dental models corresponding to the teeth of the dental prosthesis;

- virtually arranging the virtual dental models in relation to the 3D digital representation of the patient's gingiva; Y

- generate a virtual external gingival surface of the gingival part of the dental prosthesis.

A computer program product is described which comprises program code means for causing a data processing system to perform the method of the present invention, when said program code means is executed in the data processing system.

In some examples, the computer program product comprises a computer-readable medium that has the program code media stored therein.

A non-transient computer-readable medium is described that stores therein a computer program, wherein said computer program is configured to make computer-assisted modeling of a digital design of a dental prosthesis for a patient, said dental prosthesis comprising a gingival part and a dental part comprising a set of dental prosthesis teeth, where the modeling comprises: obtaining a 3D digital representation of the patient's gum, obtaining virtual dental models corresponding to the teeth of the dental prosthesis, virtually arranging the dental models in relation to the 3D digital representation of the patient's gingiva and generate a virtual external gingival surface of the gingival part of the dental prosthesis.

A data processing system is described to model a digital design of a dental prosthesis for a patient, said dental prosthesis comprising a gingival part and a dental part comprising a set of dental prosthesis teeth, wherein the system comprises

- a data processing unit configured to obtain a 3D digital representation of the patient's gingiva, and to obtain virtual dental models corresponding to the teeth of the dental prosthesis; and - a non-transient computer-readable medium having one or more computer instructions stored therein, wherein said computer instructions comprise instructions for virtually organizing the virtual dental models in relation to the 3D digital representation of the patient's gingiva, and to generate a virtual external gingival surface of the gingival part of the dental prosthesis when said instructions are executed in said data processing unit.

A system is described for modeling a digital design of a dental prosthesis for a patient, said dental prosthesis comprising a gingival part and a dental part comprising a set of dental prosthesis teeth, wherein the system comprises

- a scanner unit configured to obtain a 3D digital representation of the patient's gingiva, - a unit configured to obtain virtual dental models corresponding to the teeth of the dental prosthesis; Y

- a non-transient computer-readable medium having one or more computer instructions stored therein, wherein said computer instructions comprise instructions for virtually arranging the virtual dental models in relation to the 3D digital representation of the patient's gingiva, and generating a virtual external gingival surface of the gingival part of the dental prosthesis.

According to one aspect, the invention is a method for modeling a digital design of a dental prosthesis for a patient, said dental prosthesis comprises a gingival part and a dental part comprising a set of teeth, where the method comprises:

- obtain a 3D digital representation of the patient's gingiva;

- obtain virtual dental models corresponding to the teeth of the dental prosthesis;

- virtually arranging the virtual dental models in relation to the 3D digital representation of the patient's gingiva; Y

- generate a virtual external gingival surface of the gingival part of the dental prosthesis.

A method for manufacturing a dental prosthesis for a patient is described, wherein the dental prosthesis comprises a gingival part and teeth of dental prosthesis, wherein the method comprises:

- obtaining a digital dental prosthesis design, where the digital dental prosthesis design is modeled using the method according to the present invention;

- manufacture at least part of the dental prosthesis by means of computer aided manufacturing (CAM).

When virtual dental models have been arranged virtually relative to the 3D digital representation of the patient's gingiva, the virtual external gingival surface of the gingival portion of the dental prosthesis can be generated using a number of computer-implemented techniques, such as by a process of sliding or copying or modifying suitable surfaces of the 3D digital representation of the patient's gums.

It is an object of the present invention to provide a method for digitally designing a dental prosthesis by virtually arranging the teeth of the dental prosthesis and virtually generating the gingival part of the dental prosthesis so that a dental prosthesis manufactured from the digital design has an appearance and nice touch.

The outer gingival surface of a fabricated dental prosthesis is visible when the dental prosthesis is disposed in the patient's mouth.

It is an object of the present invention to provide that the generated virtual external gingival surface is such that a dental prosthesis manufactured from the digital design of the dental prosthesis has an aesthetically pleasing and natural appearance.

It is an object of the present invention to provide that the generated virtual external gingival surface is such that a dental prosthesis manufactured from the digital design of the dental prosthesis is formed such that the external gingival surface causes minimal discomfort to the patient when using the dental prostheses.

The gingival portion of the dental prosthesis comprises an internal gingival surface that faces or contacts the surfaces of the patient's oral cavity when the dental prosthesis is disposed in the patient's mouth. Preferably, the digital design of the dental prosthesis also comprises a corresponding virtual internal gingival surface.

In some embodiments, the method comprises generating the virtual inner gingival surface.

It is an object of the present invention to provide that the internal gingival surface of a dental prosthesis manufactured from digital design causes minimal discomfort to the patient when wearing the dental prosthesis. In some embodiments, the virtual external gingival surface and the virtual external gingival surface are generated concurrently.

In some embodiments, the 3D digital representation obtained from the patient's gingiva refers to the patient's upper jaw, the patient's lower jaw, or both.

In some embodiments, the portion of the patient's gingiva (s) that is scanned when the 3D digital representation is obtained comprises one or more healthy teeth, such as when the digital design is of a partial denture.

When designing a denture for one of the patient's jaws, it may also be relevant to scan the opposing jaw even though no denture is needed for this jaw. When the 3D digital representation of the patient's gums comprises the opposing jaw and associated teeth, the design of the dental prosthesis can take into account the occlusion of the teeth.

In some embodiments, a part of the virtual external gingival surface is formed by copying or transferring the corresponding part of the obtained 3D digital representation. This provides the advantage that the gingival part of a dental prosthesis made from the digitally designed dental prosthesis will have an external surface that resembles the natural surface of the oral cavity so that the dental prosthesis will have a more pleasant and natural appearance. . Wearing the denture will also cause less discomfort to the patient when, for example, the blade portion of the denture resembles the patient's own blade.

In some embodiments, the portion of the patient's gingiva (s) that is scanned when the 3D digital representation is obtained refers to at least the alveolar ridge and / or the paddle on which the dental prosthesis is to be arranged so that the obtained 3D digital representation of the gums comprises data in relation to the alveolar ridge and / or the paddle.

In some embodiments, the alveolar ridge and / or the palette of the obtained 3D digital representation is used in the design of the dental prosthesis, as used when generating the virtual external gingival surface of the gingival portion of the dental prosthesis. For example, the virtual outer surface of the gingival portion of the dental prosthesis on the alveolar ridge can then be designed to resemble corresponding surfaces on the patient's alveolar ridge, so that the fabricated dental prosthesis will appear more natural.

It may be advantageous that the dental prosthesis design comprises copying / transferring the shape of the patient's own pallet area from the 3D digital representation of the patient's gums to the dental prosthesis design, as this may improve the fit of the dental prostheses. Furthermore, it enables a dental prosthesis design in which the paddle portion of the virtual external gingival surface is shaped to the natural paddle of the patient. In some embodiments, a surface of the dental prosthesis configured to contact or face a section of the patient's gums is designed by copying or transferring the portion of the 3D digital representation of the patient's gums corresponding to this section.

This can have the advantage that the patient may feel less discomfort when they have the denture arranged in their mouth.

The virtual external gingival surface of the gingival portion of the dental prosthesis can be generated concurrently with the virtual gingival surface configured to face or contact the appropriate surface of the patient's oral cavity.

In the context of the present invention, the occlusal plane can be represented by the following three points in a toothed mandible: the contact point of the incisal edges of the lower central incisors (incisal point), and the tips of the distobuccal cusps of the lower second molars. This is mainly at the level of the lip closure line.

In the context of the present invention, the phrase "digital design of a dental prosthesis" is used interchangeably with the phrase "digital design of dental prosthesis".

In the context of the present invention, the phrase "mandibular occlusion rim" is used interchangeably with the phrase "lower wax rim."

In the context of the present invention, the phrase "maxillary occlusion rim" is used interchangeably with the phrase "upper wax rim".

In the context of the present invention, the phrase "wax rim" is used interchangeably with the phrase "wax occlusal rim model".

Various steps of the method can be implemented by computer so that digital precision and efficiency can be applied to a traditionally demanding technical process. The invention provides that technicians can model highly aesthetic and functional dental prostheses while significantly shortening the design step.

The dental prosthesis design workflow can include adjusting the occlusion, modeling the gingival design, placing teeth, and making fine adjustments such as bite height and more. With a computer implementation of the method, the operator can use computer-implemented free-form sculpting tools and dynamic virtual articulation in modeling the digital design of the dental prosthesis and make all necessary adjustments for optimal occlusion, aesthetics, and functionality.

The teeth part of the dental prosthesis can be based on fixed-size precast acrylic teeth or on custom individual teeth made, for example, using CAD / CAM technology.

The invention provides that the operator can quickly adjust all teeth, upper and lower, as well as the left and right sides, while maintaining the correct bite. Using virtual occlusal plates, the combined occlusion can be easily upgraded. A virtual joint can then be applied to optimize the dynamic occlusion of the dental prosthesis.

Occlusion can be set in different ways depending on the case or preferred workflow.

In some embodiments, a Wax Occlusal Fence model is scanned to define an upper and lower relative position and the occlusal plane of the patient.

In some embodiments, the upper / lower wax rim models are scanned separately and brought into virtual occlusion using flex-fit tools.

In some embodiments, the method comprises obtaining the occlusal plane of the patient by means of a face bow. In some embodiments, the facebow is an electronic facebow.

The electronic facebow can emit different patient-specific parameters that can be used to establish a virtual articulator, for example, as described in 3Shape patent applications WO2011 / 103876 and DK / PA 201270138.

In some embodiments, the facebow is a mechanical facebow.

After setting and adjusting the mechanical facebow for the patient's face, the facebow can be arranged on a mechanical articulator, and the articulator positions can be transferred to a virtual articulator by means of, for example, transfer plates, plates adapters, male and female plates, etc., as described in 3Shape patent applications WO2011 / 103876 and DK / PA 201270138.

In some embodiments, the method comprises obtaining the occlusal plane of the patient by physical impressions of the patient's upper and lower gums and / or by one or more measurements of the patient's face and mouth. Physical impressions can be obtained by using a tray filled, for example, with edge molding material and / or impression material.

The tray can be a custom dental impression tray, as described in 3Shape patent application PCT / EP2012 / 062684.

The tray can be made of a thermoplastic material.

In some embodiments, the method comprises:

- obtain a 3D digital representation of the physical impression of the patient's upper jaw;

- obtain a 3D digital representation of the physical impression of the patient's lower jaw; Y

- Obtain a 3D digital representation of the physical impressions of the patient's upper jaw and lower jaw arranged together.

In some embodiments, the patient's upper jaw and lower jaw are disposed together in occlusion.

It is an advantage to obtain a 3D digital representation of the combined physical impressions of the upper and lower jaw, as this can indicate their correct relative positions, so that the dental prosthesis can be designed appropriately.

In some embodiments, the method comprises taking measurements of the patient's face and mouth. Measurements can be made by the dentist using different measuring devices. The measuring device can be, for example, a component that is attached to the gingiva and / or lips of the patient. The component can be attached using, for example, impression material, bite registration material, biocompatible glue, etc.

Measurements can be the correct vertical height of the dental prosthesis, centric relationship, lip support, bite plane, midline, smile line, central incisal line, etc.

The occlusal plane can be obtained by a combination of using a face bow, taking measurements of the patient's face and mouth, obtaining physical impressions, and / or obtaining wax rings.

In some embodiments, the method comprises providing a straight occlusal plate.

In some embodiments, the method comprises providing a curved occlusal plate.

Virtual occlusal plates can be curved, bent, flat, straight, etc. The simplest type of occlusal plate can be a flat plate. However, often a patient's bite is not characterized by a completely flat bite or occlusion, and then a curved occlusal plate can be used.

The sagittal curve of the patient's mouth can determine the curvature of the occlusal plate.

The sagittal curve can be derived from the patient by moving the models of the patient's lower and upper jaw relative to each other in a mechanical articulator and using the pin of a face bow to mark the movements in the silicone material underneath the pin. . Then movements can be recorded made in the silicone material and the same movements can be performed either in a physical articulator or in a virtual articulator, as described in 3Shape patent applications US 61 / 664,343 and DK PA 2012 70371. This can be done if the patient still has teeth in his / her mouth. If the patient has lost teeth, then a standard plate can be used for movement.

In some embodiments, the method comprises selecting a virtual occlusion plate to model the patient's dental prosthesis.

In some embodiments, the method comprises providing a virtual occlusal plate in relation to the 3D digital representations of the wax rims and / or the 3D digital representation of the patient's gums, and virtually arranging the virtual dental models in relation to the occlusal plate. virtual.

This can provide that virtual dental models can be arranged virtually easily and quickly in relation to each other and / or in relation to the 3D digital representation of the patient's gingiva, that is, in relation to the gingival part of the dental prosthesis.

In some embodiments, the virtual dental models in the lower jaw or the upper jaw are arranged in occlusion by means of a virtual occlusal plate, and the virtual dental models are then arranged in the upper jaw or the lower jaw, respectively, relative to dental models already arranged in the opposing jaw.

If, for example, the patient has lost his teeth for a long time, for example, if the person is an older person, then the upper arch will have shrunk and the lower arch will have expanded, and the lower arch is therefore , the dominant arch, and the teeth will be laid out in the lower jaw first, and then later the teeth will be laid out in the upper jaw relative to the teeth in the lower jaw.

If, for example, the patient is a younger person who has only recently lost his teeth, then the upper jaw has not started to shrink yet, and the lower jaw has not started to expand, and in this case the upper jaw is the mandible or dominant arch, and the teeth will be arranged first in the upper jaw, and then later the teeth will be arranged in the lower jaw relative to the teeth in the upper jaw.

A virtual articulator can be used to test and verify the occlusion.

Alternatively and / or additionally, a suitable digital test, performed by means of an algorithm, can be used to design, test and / or verify the occlusion.

In some embodiments, the virtual dental casts are virtually fitted to the occlusal plate.

Tight virtually means fixed, attached, held, clamped, held in virtual contact with the occlusal plate, etc. In this way, even though the operator adjusts the position, orientation and / or shape of the virtual dental models, the dental models remain in the occlusion given by the occlusal plate.

In some embodiments, the method comprises adjusting the curvature of the occlusal plate to provide that the occlusal plate substantially follows the curvature of the patient's jaws.

In some embodiments, the method comprises adjusting the curvature of the occlusal plate by virtually pulling one or more control points on the occlusal plate.

Control points can be pulled or dragged up, down, to the right side, to the left side, etc., thereby altering the curvature of the occlusal plate.

The occlusal plate can be straight by default, and the operator can then adjust the curvature of the occlusal plate in relation to the specific patient case.

In some embodiments, the method comprises selecting virtual dental models from a virtual library comprising virtual sets of dental models, such as selecting a set of dental models from a virtual library.

In some embodiments, the different sets of dental models in the virtual library have different dispositions of the dental models, such as different dispositions of the teeth with respect to each other. In some embodiments, the different sets of dental models in the virtual library have different tooth shapes and / or sizes, such as round, square, triangular, short, long, wide, and / or narrow.

In some embodiments, a set of dental casts for the lower jaw and / or a set of dental casts for the upper jaw are selected.

In some embodiments, the lower jaw set of teeth and the upper jaw set of teeth are a pair that fit together and are arranged in occlusion.

In this way, the shape of the opposing teeth fits together, for example, the cusps of the opposing posterior teeth in the lower and upper jaw coincide with each other and fit together.

In some embodiments, the sets of dental models in the library are provided by 3D scanning of physical dentures that comprise the physical versions of the dental models arranged in the sets. In this way, the library sets can be obtained by building dentures manually, scanning the dentures, where the artificial teeth are arranged in proper occlusion, and then saving this scan as a tooth library configured for the dental prosthesis.

In some embodiments, the virtual dental models are aligned relative to the dental model sets, such as where one or more virtual dental models are aligned relative to the other teeth of the dental model set in which they are comprised and / or in relationship with the set of dental models for the other jaw.

This provides that the virtual dental models can be arranged very well in relation to the 3D digital representation of the upper and / or lower jaw.

In some embodiments, the dental models from different sets of dental models are combined for the dental prosthesis.

For example, beautiful and aesthetic dental models for anterior teeth are selected from a first set of teeth, and robust and less aesthetic dental models are selected for posterior teeth or molar teeth.

For example, tall models are selected for the anterior teeth and low dental models are selected for the posterior teeth, if the patient's mouth does not provide enough space at the back for tall teeth.

In some embodiments, the method comprises virtually adjusting the position, shape, and / or orientation of one or more of the dental models in the assemblies.

It is an advantage to adjust the position, shape and / or orientation of one or more of the dental casts to ensure that the dental casts fit the patient and to ensure that occlusion is obtained and / or maintained.

3Shape's software called Smile Composer can be used to adjust the position, shape and / or orientation of one or more dental models.

In some embodiments, virtually adjusting the position, shape, and / or orientation of one or more of the dental models in the assemblies comprises:

- transfer a tooth model;

- rotate a tooth model; me

- transform a tooth model.

In some embodiments, the occlusion of the lower jaw set of teeth and of the upper jaw set of teeth is maintained when adjusting the position, shape and / or orientation of one or more of the dental casts in the set (s). sets.

In some embodiments, interproximal contact is maintained between neighboring dental casts, when adjusting the position, shape, and / or orientation of one or more of the dental casts in the set or sets.

In some embodiments, the method comprises virtually adjusting the position, shape, and / or orientation for a group of dental models. The setting can be identical for all teeth in that group or it can scale with the distance of a selected tooth in the group. Scaling can be such that the setting increases or decreases with distance from the selected tooth.

In some embodiments, the method comprises replacing one or more dental models in the selected set of teeth with dental models from another set of teeth in the library.

In some embodiments, the method comprises virtually designing one or more of the teeth for the dental prosthesis. The teeth of the dental prosthesis can then be manufactured from the virtually designed teeth. In this way, instead of using pre-made dental prosthesis teeth, a dental designer can design one or more of the teeth for the dental prosthesis from scratch, and the designed teeth can then be manufactured, for example, by rapid manufacturing methods, such as 3D printing, milling, sintering, etc. Either all denture teeth or only some teeth can be designed from scratch.

In some embodiments, the method comprises providing a number of characteristic points in the 3D digital representation of the lower jaw and / or in the 3D digital representation of the upper jaw.

In some embodiments, the feature points are used to determine the placement of dental casts on the mandible (s).

In some embodiments, the virtual set of dental models selected from a virtual library of dental models is selected based on the relative positions of the feature points.

In some embodiments, providing the number of feature points comprises an operator virtually placing the feature points.

In some embodiments, providing the number of feature points comprises that the feature points are automatically positioned.

Feature points can be automatically placed or placed by the operator on the 3D digital representation of the mandible (s) based on certain placement rules.

In some embodiments, the signature points on the lower jaw comprise one or more of:

- a retromolar pad # 1;

- a retromolar pad # 2;

- a first canine point;

- a second canine point; Y

- a central ridge point.

In some embodiments, the signature points on the upper jaw comprise one or more of:

- tuberosity # 1;

- tuberosity # 2;

- a first canine point;

- a second canine point; Y

- a central ridge point.

Tuberosities can be defined in relation to or based on the distance between the canines.

The distance between the canines can further define the size of the artificial teeth of the dental prosthesis, such as the width of the teeth. In this way, the set of dental models in the library can be selected based on the distance between the canines.

Traditionally, precast teeth are physically arranged in wax by ravaging the wax to make room for the precast teeth. Waxed teeth can be denoted a test, since the patient can try it in his mouth to see if it fits. If it doesn't fit well enough, the teeth can be adjusted in the wax. When the trial fits the patient, the trial can be placed in a mold where the wax can melt and the acrylic can replace the wax around the precast teeth.

According to the present method, in some embodiments, a trial denture is printed when the denture has been designed.

The patient can then try on the printed trial denture in their mouth to see if it fits. If it does not fit well enough, the teeth can be adjusted in the printed test, if the printed material allows this.

In some embodiments, a photopolymerizable material is used to print the trial denture.

For example, a material can be used that is photopolymerizable, so that the printed material is ductile, moldable, or formable prior to photopolymerization so that the teeth can be fitted in the gingival portion. When the trial denture fits into the patient, the trial can be light cured to harden the material to ensure that the teeth remain in position.

In some embodiments, the printed trial denture is 3D scanned after a potential fit of the teeth in the trial denture.

It can be easy to record the adjusted teeth on the printed trial denture, as the position and orientation of the teeth on the trial denture are only slightly adjusted relative to their original position and orientation on the printed trial denture. .

In some embodiments, a trial denture is fabricated in wax, the wax trial denture is 3D scanned, and based on the 3D scan of the wax trial denture, an acrylic final denture is printed.

Instead of producing a trial denture, a digital trial can be performed using a virtual articulator to test whether the denture will fit the patient. If the 3D digital representation of the patient's gingiva is of good quality and the virtual dental models are properly arranged relative to the 3D digital representation of the teeth, then a trial denture may not be required and the digital trial using a Virtual articulator may be sufficient to ensure that the dental prosthesis fits the patient.

In some embodiments, the method comprises defining a 3D gingival streak that marks an outer boundary curve of the dental prosthesis directly on the 3D digital representation of the patient's gum or on the 3D scanned trial dental prosthesis when one of these is viewed. on a computer screen. Based on the 3D gingival stria and the arrangement of virtual dental models, a computer software can implement various steps of the method and automatically design the gingival part of the dental prosthesis, so that it is perfectly shaped to fit the teeth of the dental prosthesis. . This can be done with limited effort on the part of the operator. Anatomical details of the gingival part can be added with the operator's own artistic touch using computer-implemented virtual sculpting and editing tools.

When the digital design modeling of the dental prosthesis designs is completed, the resulting virtual model of the dental prosthesis is completely ready for efficient emission on a variety of milling machines or 3D printers. The gingival portion of the dental prosthesis can be produced to perfectly match pre-fabricated acrylic teeth or custom fabricated teeth.

In some embodiments, the method comprises defining a 3D gingival streak in relation to the 3D digital representation of the patient's gingiva. The 3D gingival streak is configured to define a gingival edge or boundary of the dental prosthesis, that is, the circumference / outer boundary of the gingival portion of the dental prosthesis.

In computer-implemented embodiments, the 3D gingival streak can be drawn directly on the 3D digital representation of the patient's gingiva on a computer screen.

The system of the invention can automatically design the gingival part of the dental prosthesis and provide that it is perfectly formed to fit the teeth.

In some embodiments, the method comprises virtually arranging the virtual dental casts in relation to the gingival portion of the dental prosthesis.

In some embodiments, part of the 3D gingival streak is disposed in the gum groove of the patient.

In some embodiments, part of the 3D gingival streak is disposed on the ah line of the patient.

In some embodiments, the virtual external gingival surface is configured to connect the 3D gingival streak and virtual dental models, that is, the generated virtual external gingival surface is formed such that it is limited, at least in part, by the 3D gingival streak. and the surface of virtual dental models.

In some embodiments, the gingival lines of the tooth are defined for said virtual dental models and said virtual external gingival surface contacts said virtual dental models on said gum-tooth line. This has the advantage that the appearance of the dental prosthesis can be determined, at least in part, by the gum-tooth line. In some cases, the gum-tooth line is predefined based on the tooth structure of the dental prosthesis, while in other cases an operator defines the gum-tooth line. In both cases, the shape of the virtual external gingival surface in the dental prosthesis can be determined, to some extent, automatically based on the defined gingival lines of the tooth.

In some embodiments, the method comprises connecting the virtual external gingival surface with the gingival lines of the tooth in the virtual dental models.

In some embodiments, the method comprises extending the virtual external gingival surface into the interproximal gap between the dental casts.

It is an advantage that the external gingival surface extends past the gingival lines of the tooth in virtual dental models in the gaps between the teeth, as this provides a natural and aesthetic appearance of the dental prosthesis and provides that parts of the food do not become Capture in the interproximal gaps.

In some embodiments, the virtual external gingival surface is generated at least in part by a displacement of a corresponding portion of the 3D digital representation of the patient's gingiva.

This has the advantage that a natural appearance can be easily obtained from this part of the dental prosthesis. In addition, the patient may experience less discomfort when wearing the denture if its outer surface resembles the natural anatomy of the patient's tissue. Also the design of this part of the dental prosthesis can be made highly automatic, for example by activating a virtual button on a user interface, this part can be designed automatically.

In some embodiments, the virtual external gingival surface is generated, at least in part, by a sliding process.

In some embodiments, at least part of the virtual outer gingival surface is shaped to resemble corresponding surfaces on the patient's natural gingiva. The corresponding surfaces can refer to the visible part of the alveolar ridge and the paddle, so that at least the visible surface of the gingival part of the dental prosthesis is shaped according to the natural appearance of the patient's gingiva.

In some embodiments, at least part of the shape of the virtual external gingival surface is selected from a gingival library.

This has, for example, the advantage that the dental prosthesis can be designed quickly and largely automatically. The use of a gingival library with a virtual, natural-looking external gingival surface selection provides that an aesthetically appealing dental prosthesis can be easily designed.

In some embodiments, at least part of the shape of the virtual external gingival surface is modified or generated using a virtual freeform sculpting tool. This can be implemented with 3Shape's Dental System ™ sculpting and editing tools that allow you to easily add anatomical details to the gingiva with an operator's own artistic touch.

In some embodiments, the virtual external gingival surface is generated at least in part by a virtual marginal gingiva.

In some embodiments, the virtual marginal gingiva is disposed in the gingival portion of the dental prosthesis where the gingiva meets the lingual, labial, or buccal aspect of the virtual dental models.

In some embodiments, generating the virtual external gingival surface comprises generating the virtual marginal gingiva and connecting the marginal gingiva to the 3D gingival streak.

In some embodiments, generating the virtual external gingival surface comprises connecting the 3D gingival streak with the virtual dental models and then generating the marginal gingiva.

In some embodiments, the 3D gingival streak is connected to a gum-tooth line in virtual dental models.

In some embodiments, the virtual external gingival surface is configured to be fitted.

An initial version of the virtual external gingival surface, for example, can be selected from a library and the method may then comprise an adjustment of the selected initial version to customize the virtual external gingival surface to the oral situation of the patient. This provides the advantage that an aesthetically attractive dental prosthesis that resembles the natural surface in the oral cavity can be easily designed.

In some embodiments, the adjustment is done by pulling one or more control points arranged on the virtual external gingival surface.

In some embodiments, the virtual outer gingival surface is configured to be adjusted so that it curves inwardly between the patient's gums and the gum-tooth line in dental models.

An inward curvature between the gum-tooth line and the gums provides a natural-looking gingival portion of the denture.

In some embodiments, the method comprises virtually designing the outer gingival surface of the dental prosthesis to be rounded at the gingival edges or limits.

If the gingival edges or limits are rounded, it is more comfortable for the patient to wear the dental prosthesis, since a gingival edge or limit that is not rounded will be quite uncomfortable for the patient since the edges and limits will then feel very sharp. for the gums and when touched by the tongue.

In some embodiments, the method comprises virtually designing the outer gingival surface of the mandible or part of the lower jaw of the dental prosthesis to be large enough for the tongue to touch and rest on a portion of the outer gingival surface. By this means, the tongue can act as an active prosthetic support for the lower jaw portion of the denture, which might otherwise have a tendency to fall back into the mouth.

In some embodiments, the method comprises virtually designing a protrusion at the gingival edge or boundary of the palate or paddle area of the dental prosthesis.

The function of the protrusion is to create a vacuum under the palate or paddle area of the upper jaw denture, whereby the upper part of the denture will be suctioned into the patient's own palate. In some embodiments, the method comprises designing virtually a dent in the center of the palate or the paddle area at the gingival edge or boundary of the dental prosthesis.

Two salivary glands exit the palate and the dental prosthesis should be designed so as not to cover these glands.

In some embodiments, the virtual external gingival surface is generated, at least in part, by one or more virtual cervical protrusions. The virtual cervical protrusions can be configured to resemble the protrusions defined by the ends of the subgingival root of the teeth.

In some embodiments, the method comprises identifying an occlusal plane of the dental prosthesis.

In some embodiments, the method comprises adjusting the height of the bite.

In some embodiments, the method comprises forming an upper wax rim for the patient's maxillary arch. In some embodiments, the method comprises scanning said upper wax rim to obtain a 3D digital representation of the upper wax rim.

In some embodiments, the method comprises forming a lower wax rim for the patient's mandibular arch. In some embodiments, the method comprises scanning said lower wax rim to obtain a 3D digital representation of the lower wax rim.

In some embodiments, the method comprises digitally forming 3D representations of a lower wax rim for the patient's mandibular arch and / or digitally forming 3D digital representations of an upper wax rim for the patient's maxillary arch, such as by selecting digital representations. 3D wax rim from a wax rim library and digitally shape these 3D digital representations to fit the patient's oral situation using a virtual manipulation tool

Based on the 3D digital representations of the wax rims, the location of the occlusal plane, the medial plane marked on a wax rim, or the incisal edge of the anterior teeth of the mandible can be obtained, for example, to derive the plane. occlusal of the patient. Wax rims can be obtained by scanning in the patient's mouth or by scanning a physical model from a bite registration. The scan can use a benchtop scanner or an intraoral scanner.

Wax rims can be used for two functions, which is to adjust and ensure correct occlusion of the denture, and to shape the patient's lips so that the teeth on the denture fit underneath the denture. lips, without causing the lips to collapse in the mouth or causing the lips to move away from their natural position

In some embodiments, the method comprises virtually arranging the dental models in relation to the 3D digital representations of the wax surround.

In some embodiments, the arranged dental models virtually conform to the 3D digital representation of the wax surround.

In some embodiments, the dental models are automatically arranged at a predefined distance from the 3D digital representation of the wax rim, such as a predefined distance along a direction in the occlusal plane.

In some embodiments, the centerline and / or the midline of the patient's face are recorded or outlined on the wax rings.

The registered centerline and midline are used when designing the dental prosthesis so that the artificial teeth in the dental prosthesis are aesthetically and / or functionally correctly arranged in relation to the patient's face.

In some embodiments, the method comprises obtaining 3D digital representations of both the mandibular gingiva and the maxillary gingiva of the patient.

In some embodiments, the method comprises arranging physical models of the patient's mandible and maxilla and the corresponding lower and upper wax rims in a stack according to their relative position in occlusion, and obtaining a 3D digital representation of this stack.

The stack can be scanned before the gingiva models or after the gingiva models. In a workflow, the stack is laid out and scanned. The physical model of the maxilla and the wax rings are then removed and scanned together. Finally the physical model of the jaw is scanned.

In some embodiments, the method comprises virtually aligning the 3D digital representations of the patient's mandibular and maxillary gums and the 3D digital representation of the stack, such that a combined gingiva-wax rim model is generated.

In some embodiments, the gingiva-wax rim patterns are defined for each of the maxilla and mandibular. This provides, for example, the advantage that the gingiva-wax surround patterns can be arranged together to provide information on the relative arrangement of the gums in occlusion.

In some embodiments, the relative disposition of the gingiva is derived from the maxillary arch and the occlusal plane. In some embodiments, the relative disposition of the gingiva is derived from the mandibular arch and the occlusal plane. In both cases, it can be derived from the 3D digital representation of the stack.

In some embodiments, the method comprises obtaining a 3D digital representation of the lower wax rim, such as by scanning the formed upper wax rim.

This has the advantage that the 3D digital representation of the lower wax rim can be used in the digital design of the dental prosthesis, so that the information provided by the lower wax rim can be used. In some embodiments, the method comprises obtaining a 3D digital representation of the upper wax rim, such as by scanning the formed upper wax rim.

This has the advantage that the 3D digital representation of the upper wax rim can be used in the digital design of the dental prosthesis, so that the information provided by the upper wax rim can be used. In some embodiments, the 3D digital representations of the upper and lower wax rims are brought virtually into occlusion, and where the position and orientation of the occlusal plane is determined therefrom. The relative arrangement of the mandibular and maxillary arch in occlusion can also be determined from these. In some embodiments, the 3D digital representations of the upper and lower wax rims are arranged virtually relative to the 3D digital representation of the patient's mandibular and maxillary gums, such that the combined gingiva-wax rim model is generated.

In some embodiments, the lip line of the dental prosthesis is derived from the combined gingiva rim model.

In some embodiments, the incisal edge of the anterior teeth of the mandibular dental prosthesis is derived from the combined gingiva-wax rim model.

In some embodiments, the occlusal plane is derived from the combined gingival rim-wax model.

In some embodiments, the incisal edge of the anterior teeth of the maxillary dental prosthesis is derived from the combined gingiva-wax rim model.

The incisal edge of the maxillary anterior teeth can be marked on the upper wax rim in cases where the maxillary anterior teeth extend below the incisal edge of the mandibular anterior teeth. In some embodiments, the occlusion or occlusal plane of the patient's mouth is derived from the upper and lower wax rims.

The occlusal or occlusal plane derived from the mouth can be provided as the occlusal plane or occlusion of the dental prosthesis.

In some embodiments, the shape of the patient's lips is derived from the upper and lower wax rims.

The shape derived from the lips can be used when designing the dental prosthesis. In this way it is possible to determine from the wax rings how much space is available for the teeth of the dental prosthesis and the gingiva behind the lips. The teeth of the dental prosthesis and the gingival part should not occupy more or less space than adequate, since otherwise the patient's lips will not cover the dental prosthesis in an aesthetic way.

In some embodiments, the dental models are virtually fitted within the 3D digital representation (s) of the wax rim (s) to ensure that there is sufficient space for the teeth behind the patient's lips.

Alternatively, the dental models can be fitted to the 3D digital representation of the wax surround in a suitable location to ensure that there is sufficient space for the teeth behind the patient's lips.

In some embodiments, the virtual dental models are arranged virtually in relation to the 3D digital representation of the patient's gingiva based on a visualization of the virtual dental models in relation to said combined gingiva-wax rim model.

In some embodiments, virtually arranging the virtual dental models relative to the 3D digital representation of the patient's gingiva comprises rotating and / or translating the virtual dental models relative to the 3D digital representation of the patient's gingiva.

In some embodiments, the method comprises virtually arranging at least the dental portion of the dental prosthesis in relation to a virtual articulator and performing a dynamic virtual articulation to assess the occlusion of the dental prosthesis.

In some embodiments, the method comprises determining a target shape of the teeth of the dental prosthesis. The target shape can be determined using collision detection based, for example, on a virtual dynamic articulator, a target relationship between the teeth and the gums, the space available for the gingival material of the dental prosthesis.

Virtual articulation can be performed using a virtual articulator comprising a 3D virtual model of the maxilla and a 3D virtual model of the mandible with the corresponding teeth arranged in relation to their respective jaws. The virtual maxilla and virtual mandible are moved relative to each other to simulate dynamic occlusion such that collisions occur between the teeth in the virtual maxilla and in the virtual mandible.

Articulation and occlusion of the dental prosthesis can be evaluated using a virtual dynamic articulator in which the dental prosthesis and opposing teeth are arranged. The opposing teeth can be the virtual dental models of a simultaneous or previously modeled dental prosthesis for the opposite arch. The antagonist can also be the patient's original teeth. For the case where the patient's mandibular teeth are intact and a maxillary dental prosthesis is to be modeled, the opposing teeth will be the intact set of teeth of the mandible.

In some embodiments, the method comprises:

- make a virtual joint of the dental prosthesis, and

- virtually remove a part of one or more of the dental models, if the virtual joint indicates that the removal is adequate.

Virtual removal of part of virtual dental models can be performed automatically on a joint basis or can be virtually removed by the operator.

In some embodiments, the method comprises:

- make a virtual joint of the dental prosthesis, and

- virtually adjust the position and / or orientation of one or more of the dental models, if the virtual joint indicates that the adjustment is adequate.

Virtual adjustment of the position and / or orientation of part of the virtual dental models can be done automatically based on the joint or can be done virtually by the operator. The dental models can be translated, for example, in the labial or lingual direction or they can be moved further towards the gingival part or rotated in relation to the neighboring teeth.

In some embodiments, the virtual dental models correspond to exact versions of denture teeth, such as exact versions of precast denture teeth. An initial virtual model of a tooth can correspond to the exact version of a dental prosthesis tooth.

In some embodiments, the teeth of the dental prosthesis are precast teeth, such as precast acrylic teeth. Such pre-fabricated teeth can be, for example, Vita T3M or other dental prosthetic teeth manufactured by VITA Zahnfabrik in Germany, or lvoclar Vivadent artificial teeth, such as Phonares, Vivodent, VivoTAC, lvostar, etc.

In some embodiments, the method comprises adjusting the size, shape, length, width, or thickness of the precast teeth to obtain said target shape. Adjustments may involve the removal of excess dental material for example, by devastating or by laser ablation. Adjustments may also include the addition of dental material, such as locally adding porcelain material to selected parts of the tooth. In some embodiments, the teeth of the dental prosthesis are custom teeth that are represented by dental CAD models.

Dental CAD models of denture teeth can be modified with respect to size, shape, length, width, mass distribution, or thickness to obtain such a target shape. This can be done during modeling of the digital design of the dental prosthesis, so that the shape of the tooth is also taken into consideration in the design of the gingival part of the dental prosthesis.

In some embodiments, the 3D digital representation of the patient's gingiva is obtained by scanning the patient's gingiva using an intraoral scanner.

In some embodiments, the 3D digital representation of the patient's gingiva is obtained by scanning at least part of an impression of the patient's gingiva and / or scanning at least part of a physical model of the patient's gum. Scanning can be performed by laser light scan, white light scan, probe scan, X-ray scan, and / or CT scan.

In some embodiments, the method is to model a maxillary or a mandibular dental prosthesis. For example, the teeth of the maxilla may be intact while a dental prosthesis is designed for its antagonist, that is, the jaw or vice versa.

In this case, the antagonist's teeth are scanned and a 3D digital representation of the antagonist is obtained. When the virtual dental models of the dental prosthesis are arranged, then the 3D digital representation of the antagonist is used when, for example, a virtual dynamic articulator is applied to assess the occlusion.

In some embodiments, the method is to model a maxillary and a mandibular dental prosthesis.

Virtual dental models are then obtained for both the maxillary and mandibular dental prostheses, and the virtual models of the mandibular teeth are preferably taken into account when the virtual model of the maxillary teeth is available and vice versa.

In some embodiments, at least the dental portion of a maxilla and the dental portion of a mandibular dental prosthesis are modeled simultaneously. The virtual models of the mandibular teeth and the virtual models of the maxillary teeth can be positioned, rotated, resized, etc. depending on position, rotation, size, etc. one of the other.

In some embodiments, the method is to model a complete dental prosthesis, that is, a dental prosthesis that replaces all teeth in the corresponding part of the patient's mouth.

Some of the original patient's teeth may be present in the 3D digital representation of the patient's gums, and in some cases these teeth are so healthy that they should preferably be preserved. In some embodiments, the method is to model a partial dental prosthesis, that is, a dental prosthesis that replaces some teeth in the corresponding part of the patient's mouth.

In some embodiments, at least part of the method is implemented by computer. This has the advantage that many design steps can be performed faster and with greater precision than when an operator is doing them manually.

In some embodiments, the extent of the undercut sections between the denture and the gums is controlled. For a maxillary dental prosthesis, the suction power between the dental prosthesis and the patient's gums counteracts the force of gravity to keep the dental prosthesis fixed on the patient's maxillary gums. For this dental prosthesis, a certain degree of undercuts can help the suction power and actually work to the benefit of the patient.

For mandibular dentures, it may be advantageous to block any undercuts.

In some embodiments, the method comprises performing a partial wax blocking of the undercuts.

Especially for older people, a wax lock may be required to ensure that the denture remains in the patient's mouth.

In some embodiments, the method comprises mimicking teeth.

The imitation of teeth may be such that the arrangement of the teeth of the dental prosthesis on one side of an arch is determined by imitating the arrangement of the teeth of the dental prosthesis on the opposite side of the arch, such as the imitation with respect to the plane. medial of the patient.

In some embodiments, the tooth imitation is such that the shape of the denture teeth on one side of an arch is determined by mimicking the shape of the denture teeth on the opposite side of the arch. In this way, the imitation can be with respect to the medial plane of the patient.

It is an advantage that the imitation can be performed, because then the user does not need to work or modify the arrangement or shape of all the teeth that should be designed with respect to the arrangement and shape, the user can only design the teeth, for example, in the left arch. One or more teeth can be imitated.

In some embodiments, the modeling result of the digital dental prosthesis designs is a virtual model of the dental prosthesis that is completely ready for efficient output on a variety of milling machines or 3D printers.

The method may comprise producing the gum of the dental prosthesis to perfectly match the pre-fabricated acrylic teeth or custom fabricated teeth. Often times, the teeth of the dental prosthesis are made of a first material and the gingival part is made of a second material.

In some embodiments, the method comprises virtually arranging one or more implants in relation to the virtual dental models and the gingival portion of the dental prosthesis.

In some embodiments, the method comprises virtually connecting one or more of the virtual dental models and / or the gingival portion of the dental prosthesis to the one or more implants.

The implants are connected in the lower part of the gingival part, that is, in the part of the gingival part that faces the gums of the patient, since the implants are implanted in the gums of the patient.

In this way, no superstructure, bar, frame, etc. may be required. in the dental prosthesis to connect the dental prosthesis to the implants.

In some embodiments, the method comprises virtually reducing or displacing the virtual dental casts. In some embodiments, a veneer layer can be designed on virtually offset or reduced teeth.

In some embodiments, the teeth of the virtual model are configured to be virtually reduced in size.

When the virtual tooth models correspond to physical precast teeth, these precast teeth can only be made smaller not larger and therefore the software used to design the virtual dental models can ensure that the operator or dental designer can only reduce the size of the virtual model teeth, without increasing the size of a virtual model tooth. If the dental technician wishes to have a larger tooth, he or she should select a different model tooth from the digital tooth library. In some embodiments, the method comprises virtually arranging a 2D image of the patient's lips in relation to the digital design of the dental prosthesis.

It is an advantage that the dental prosthesis design can be viewed or visualized in relation to the patient's own lips to show the expected end result to the patient for approval. The 2D image and digital design of the dental prosthesis can be aligned.

Additional details regarding the arrangement of a 2D image of the patient's lips in relation to the digital design of the dental prosthesis can be found in 3Shape patent application WO2012 / 000511. In some embodiments, the method comprises arranging and virtually aligning a 2D image of the patient's lips relative to the 3D digital representations of the wax rims.

The wax surround can be marked with markers for certain points or areas, for example, with holes in the wax that indicate the smile line, canines, etc.

In some embodiments, the method comprises defining the thickness of the gingival portion of the dental prosthesis.

The thickness can be different in different areas of the gingival part. For example, the gingiva thickness may be less at the gingiva boundaries or edges, so that the transition between the gingiva and the patient's gingiva will look as natural as possible through a smooth transition.

The present invention relates to different aspects including the method and system described above and below, and the corresponding methods and systems, each producing one or more of the benefits and advantages described in connection with the first mentioned aspect, and each having one or more embodiments corresponding to the embodiments described in connection with the first mentioned and / or described aspect in the accompanying embodiments.

In particular, a method for manufacturing a dental prosthesis for a patient is described, wherein the dental prosthesis comprises a gingival part and teeth of dental prosthesis, wherein the method comprises:

- obtaining a digital design of dental prosthesis, where the digital design of the dental prosthesis is modeled using the method according to any of the embodiments;

- manufacture at least part of the dental prosthesis by means of computer aided manufacturing (CAM).

Furthermore, the invention relates to a computer program product comprising program code means for causing a data processing system to perform the method according to any of the embodiments, when said program code means is executed on the system. data processing device and a computer program product, comprising a computer-readable medium that has stored the program code means therein.

Also described is a non-transient computer-readable medium that stores therein a computer program, wherein said computer program is configured to make computer-assisted modeling of a digital design of a dental prosthesis for a patient, said dental prosthesis comprising a gingival part and a dental part comprising a set of dental prosthesis teeth, where the modeling comprises: obtaining a 3D digital representation of the patient's gum, obtaining virtual dental models corresponding to the teeth of the dental prosthesis, virtually arranging the dental models virtual relative to the 3D digital representation of the patient's gingiva, and generate a virtual external gingival surface of the gingival part of the dental prosthesis. Also described is a system for modeling a digital design of a dental prosthesis for a patient, said dental prosthesis comprising a gingival part and a dental part comprising a set of dental prosthesis teeth, wherein the system comprises

- a scanner unit configured to obtain a 3D digital representation of the patient's gingiva, - a unit configured to obtain virtual dental models corresponding to the teeth of the dental prosthesis;

- a non-transient computer-readable medium having one or more computer instructions stored therein, wherein said computer instructions comprise instructions for virtually arranging the virtual dental models in relation to the 3D digital representation of the patient's gingiva, and generating a virtual external gingival surface of the gingival part of the dental prosthesis.

A user interface is described for modeling a digital design of a dental prosthesis for a patient, said dental prosthesis comprising a gingival part and a dental part comprising a set of dental prosthesis teeth, where the user interface is configured to:

- visualize a 3D digital representation of the patient's gingiva and virtual dental models corresponding to the teeth of the dental prosthesis;

- virtually arranging the virtual dental models in relation to the 3D digital representation of the patient's gingiva; Y

- generate a virtual external gingival surface of the gingival part of the dental prosthesis.

In some embodiments, the user interface is configured to be viewed by an operator using a computer screen and to allow the operator to enter data and make choices presented on the user interface by means of a computer keyboard or computer mouse.

In some embodiments, the user interface is configured to obtain and display 3D digital representations of an upper and / or lower wax rim along with the 3D digital representation of the patient's gingiva and / or virtual dental models corresponding to the teeth. of the dental prosthesis.

The user interface can be implemented using a computer system where the user interface is displayed using a computer screen that displays the different components of the user interface, such as data entry fields and virtual push buttons configured to perform one or more steps of a method according to an embodiment of the invention. Data input means such as a computer mouse and a computer keyboard can be connected to the computer system and used to input data into the user interface and to make selections, for example, by pressing said virtual buttons using the computer mouse.

In some embodiments, the user interface is configured to allow an operator to carry out a method according to an embodiment of the invention. Preferably, at least one of the steps of obtaining a 3D digital representation of the patient's gingiva, obtaining virtual dental models corresponding to the teeth of the dental prosthesis, and generating a virtual external gingival surface of the gingival part of the prosthesis dental can be performed by the operator using said user interface. In some embodiments, the steps of the method are performed sequentially and the user interface can be configured to sequentially provide a visual representation of the steps to the operator so that the sequence of the user interface matches that of the method. In some embodiments, the user interface is configured to simultaneously provide a visual representation of two or more of the steps to the operator.

Brief description of the drawings

The above and / or additional objects, features and advantages of the present invention will be further elucidated by the following illustrative and non-limiting detailed description of embodiments of the present invention, with reference to the attached drawings, where:

Figure 1 shows a flow chart of an embodiment of the invention.

Figures 2 to 5 show some steps in modeling the digital design of a dental prosthesis.

Figure 6 shows how the imitation can be applied in the modeling of the dental prosthesis.

Figure 7 shows a 3D digital representation of the gingiva for a toothless upper jaw (maxilla).

Figures 8 and 9 illustrate the use of 3D digital representations of the wax surrounds when arranging the virtual dental models.

Figure 10 illustrates how a 3D gingival streak can be defined.

Figure 11 shows a virtual external gingival surface of the gingival part of the dental prosthesis.

Figure 12 shows how a virtual ruga structure can be added to the modeled dental prosthesis.

Figure 13 illustrates how the interproximal gingiva can be modified.

Fig. 14 shows an example of setting teeth on the occlusal plate.

Fig. 15 shows an example of delivery of an occlusal plate.

Fig. 16 shows an example of supplying a number of feature points in the 3D digital representation of the lower jaw and upper jaw, where the feature points determine the placement of the dental casts on the mandible (s).

Fig. 17 shows an example of boundary or edge generation for the upper jaw portion of a dental prosthesis.

Fig. 18 shows an example of boundary or edge generation for the lower jaw portion of a dental prosthesis.

Fig. 19 shows an example of a virtual initial arrangement of virtual denture teeth.

Fig. 20 shows examples of the software tools available to digitally design and adjust the dental prosthesis design.

Fig. 21 shows examples of generation of the virtual gingiva of the dental prosthesis.

Fig. 22 shows examples of inspection of the digital design of the dental prosthesis.

Fig. 23 shows an example of design features in the gingival part of the dental prosthesis.

Fig. 24 shows an example of a final design of a dental prosthesis.

Fig. 25 shows examples of virtual occlusal plates.

Fig. 26 shows schematic examples of virtual external gingival surface design.

Fig. 27 shows schematic examples of the design of the upper jaw part of the dental prosthesis. Fig. 28 shows a schematic of a system according to an example of the description.

Detailed description

In the following description, reference is made to the accompanying figures, which show by way of illustration how the invention can be put into practice.

3D digital representation of the patient's gums can be obtained by directly scanning the patient's gums using an intraoral scanner or by scanning an impression or physical model of the gums. The intraoral scanner can be configured to use focus scanning, where the 3D digital representation of scanned teeth is reconstructed from focused images acquired at different depths of focus, such as the 3Shape TRIOS A / S TRIOS intraoral scanner. The focus scanning technique can be performed by generating a probe light and transmitting this probe light towards the set of teeth so that at least a part of the set of teeth is illuminated. Light returning from the set of teeth is transmitted to a camera and viewed by an image sensor in the camera by means of an optical system, where the image sensor / camera comprises an array of sensor elements. The position of the plane of focus in / in relation to the set of teeth is varied by means of the focusing optics while images are obtained from / by means of said array of sensor elements. Based on the images, the position (s) in focus of each of a plurality of sensor elements or each of a plurality of groups of sensor elements can be determined for a sequence of positions of the focus plane. The focused position can be calculated, for example, by determining the oscillation amplitude of the light for each of a plurality of the sensor elements or each of a plurality of groups of the sensor elements for a range of focus planes. From the focused positions, the 3D digital representation of the set of teeth can be derived. An impression or physical model of the patient's gums can also be scanned using, for example, a benchtop scanner based, for example, on the triangulation scheme. A triangulation 3D laser scanner uses laser light to probe the environment or object. A triangulation laser shines a laser on the object and explodes a camera to find the location of the laser spot. Depending on how far the laser touches a surface, the laser spot appears in different places in the camera's field of view. This technique is called triangulation because the laser point, the camera, and the laser emitter form a triangle. A laser beam, rather than a single laser point, can be used and then swept across the object to speed up the acquisition process.

Structured light 3D scanners project a pattern of light onto the object and observe the deformation of the pattern on the object. The pattern can be one-dimensional or two-dimensional. An example of a one-dimensional pattern is a line. The line is projected onto the object using, for example, an LCD projector or a scanning laser. A camera, slightly offset from the pattern projector, observes the shape of the line and uses a technique similar to triangulation to calculate the distance of each point on the line. In the case of a single line pattern, the line is swept across the field of view to collect distance information on one strip at a time. An example of a two-dimensional pattern is a grid or line stripe pattern. A camera is used to observe the deformation of the pattern, and an algorithm is used to calculate the distance at each point in the pattern. Algorithms for multi-line laser triangulation can be used.

Iterative Nearest Point (ICP) is an algorithm used to minimize the difference between two point clouds. ICP can be used to reconstruct 2D or 3D surfaces from different scans or subscans. The algorithm is conceptually simple and is commonly used in real time. It iteratively reviews the transformation, that is, translation and rotation, necessary to minimize the distance between the points of two raw scans or subscans. The inputs are: raw two scan or subscan points, initial estimate of the transformation, criteria to stop the iteration. The output is: refined transformation. Essentially, the steps of the algorithm are:

1. Associate points for the nearest neighbor criterion.

2. Estimate transformation parameters using a mean square cost function.

3. Transform the points using the estimated parameters.

4. lterate, that is, re-associate the points and so on.

A 3D digital representation of an object can be a mathematical representation of the 3D surface of the object derived from scan data using specialized software. The product is often called a 3D model. A 3D model represents the 3D object using a collection of points in 3D space, connected by various geometric entities such as triangles, lines, curved surfaces, etc. The purpose of a 3D scanner is usually to create a point cloud of geometric samples on the surface of the object.

3D modeling is the process of developing a mathematical representation of a metallic structure of any three-dimensional object, called a 3D model, through specialized software. Models can be created automatically, for example 3D models can be created using multiple approaches: use of NURBS curves to generate precise and uniform surface patches, polygon mesh modeling which is a faceted geometry manipulation, or polygon mesh subdivision that is an advanced mosaic of polygons, resulting in smooth surfaces similar to NURBS models.

Some 3D scanners collect distance information about surfaces within their field of view. The "image" produced by a 3D scanner describes the distance to a surface at each point in the image. For most situations, a single scanner or subscan will not produce a complete model of the object. Multiple subscanners, such as 5, 10, 12, 15, 20, 30, 40, 50, 60, 70, 80, 90 or in some cases even hundreds, from many different directions may be required to obtain information about all sides of the object. These subscans are brought into a common reference system, a process that can be called alignment or registration, and then they are merged to create a complete model.

Figure 1 shows flow diagrams of embodiments of the invention, with Figure 1a-1c illustrating some initial steps and Figure 1d showing some later steps. The vertical dotted line in the center of the page divides the flowchart into a part related to physical drives and a part related to virtual drives.

In step 101, a 3D digital representation of the patient's gums is obtained, for example, by scanning the patient's gums using an intraoral scanner and converting the data obtained by the scanner to a 3D model of the gums. The 3D digital representation of the patient's gums comprises at least the alveolar ridge in which the dental prosthesis is intended to be placed. In case the patient has any teeth to be preserved, these should preferably also be part of the 3D digital representation.

In step 105, the virtual dental models and the 3D digital representation of the patient's gums are combined, for example, by superimposing the virtual dental models on the 3D digital representation of the patient's gums, so that the virtual dental models are arranged relative to the 3D digital representation of the patient's gums. The teeth of the dental prosthesis can be prefabricated teeth such as the Vita T3M teeth and the corresponding virtual dental models are stored in a memory unit of a computer system in which the method is implemented.

The arrangement of the virtual dental models in relation to the 3D digital representation of the patient's gums and the arrangement of the virtual dental models with respect to each other can be modified to obtain an aesthetic appearance and a correct occlusion of the teeth in the prosthesis dental manufactured later. The modification can be performed manually or automatically using computer-implemented algorithms based, for example, on a virtual dynamic joint and / or a visualization of the virtual dental models together with an image of the patient's face.

The method can use collision correlation relative to the antagonist when evaluating the design of a dental prosthesis. It may be an advantage that collision correlation with the antagonist can be provided, since it is hereby easy and quick for the user to check whether there is actually enough space for the designed dental prosthesis and its teeth in the patient's mouth. Collision detection can examine the spatial arrangement of virtual dental models, such as position, direction, rotation, height, etc. of the teeth relative to each other.

An additional step is illustrated in Figure 1b compared to Figure 1a. Wax rims are formed for the upper jaw (maxilla) and lower jaw (mandibular) and a 3D digital representation of the wax rim is obtained in step 102. The 3D digital representation of the wax rim is combined with the 3D digital representation of the patient's gums in step 103 to provide the combined gingiva-wax rim model.

The virtual dental models are then arranged relative to the combined gingival rim-wax model and the final disposition of the virtual dental models can be determined.

The combination of the 3D digital representation of the wax surround, the 3D digital representation of the patient's gums and the virtual dental models can also be such that the virtual dental models are arranged relative to the 3D digital representation of the wax surround and the 3D digital representation of the patient's gums is added later, or so that the virtual dental models are arranged relative to the 3D digital representation of the gums and the 3D digital representation of the patient's wax rim is added later.

In Figure 1c, a stack is scanned 104 with physical models of the patient's mandible and maxilla and the corresponding lower and upper wax rims arranged according to their relative position in occlusion, so that a 3D digital representation of this stack is obtained. .

In step 101, 3D digital representations of both of the patient's gums are obtained, for example, by scanning the patient's gums using an intraoral scanner. The 3D digital representations of the patient's gums comprise at least the alveolar ridge in which the dentures are intended to be placed.

The 3D digital representations of the patient's mandibular and maxillary gums and the 3D digital representation of the stack are then aligned 103, such that a combined gingiva rim-wax model is generated.

In the combined model, the part corresponding to the patient's mandibular and maxillary gums in the 3D digital representation of the stack can be subtracted so that in a visualization of the combined model, the 3D digital representations of the mandibular and gingiva can be seen together. maxilla of the patient with the wax surround parts of the stack 3D digital rendering.

The stack can be scanned before or after gingiva models.

In step 105, the virtual dental models are arranged relative to the combined gingiva-wax model, for example, by overlaying the virtual dental models on the combined gingiva rim model and their arrangement is optimized 106 to provide an arrangement end of the virtual dental model in relation to the combined model.

Figure 1d shows some subsequent steps, that is, after the final arrangement of the virtual dental models is determined.

In step 107, a 3D gingival streak is defined using, for example, a pointer tool, such as a mouse, to identify the shape of the 3D gingival streak and its position relative to the 3D digital representation of the gums.

In step 108, a gum-tooth line is defined in the virtual dental models. This line marks where on the denture teeth the gingival portion of the fabricated denture will come into contact with the denture denture teeth.

In step 109, the outer surface of the gingival portion of the dental prosthesis is virtually generated. This can be done by compensating a corresponding surface of the digital 3D representation of the patient's gums and / or by a sliding process that connects, for example, a displaced gum surface and a gum-tooth line in virtual dental models. The external surface can be generated in such a way that the natural appearance of a gingiva is imitated by the gingival part of the dental prosthesis. This can be achieved by adding a virtual marginal gingiva and / or virtual ruga to the virtual external gingival surface so that a correct anatomical external surface is obtained (step 110).

At step 111, a complete virtual model of the gingival portion of the dental prosthesis is provided, for example, by forming a gingival facing surface of the gingival portion of the dental prosthesis. This can be formed as an offset of the 3D digital representation of the patient's gingiva (s).

The gingival portion of the dental prosthesis can then be fabricated in step 112 using CAM equipment operated to fabricate the generated virtual model of the gingival portion of the dental prosthesis.

Figures 2 to 5 show some steps in modeling the digital design of a dental prosthesis. The figures show cross-sectional representations of the virtual dental models and the 3D digital representation of the patient's gums at a position along the alveolar ridge of the patient's gums.

In Figure 2a, an initial virtual model of a tooth 218 is arranged relative to the alveolar ridge 221 of a 3D digital representation of the patient's gingiva according to a final arrangement, i.e. where occlusion and occlusion have been modified / evaluated. esthetics of the teeth of the dental prosthesis. An offset line 219 configured to mark the lower limit of the teeth of the dental prosthesis in relation to the gingival portion of the dental prosthesis is indicated. This line of displacement defines a section of the virtual tooth model that has to be cut in order to avoid collisions with the patient's gums and to make space for the gingival material between the gums and the teeth of the dental prosthesis.

When the initial virtual tooth model 218 is cut on the offset line 219, it is shaped according to the virtual tooth model 220 seen in Figure 2b. In several of the following figures, the cutting step of the virtual tooth model to the displacement line could also be performed after the design of the gingival part of the dental prosthesis was made.

In the figure, the groove portion 222 and the paddle portion 223 of the patient's gingiva are also indicated.

In Figure 3, a gingiva-tooth line 224 is indicated on the virtual dental model and the 3D gingival streak 225 is defined in the groove portion. The 3D gingival groove 225 can be defined automatically using computer-implemented algorithms configured to identify the groove or by input provided by the user using, for example, a computer mouse.

In Figure 4, a displacement surface 226 is defined by shifting the 3D digital representation of the patient's gums over the paddle and the alveolar to the 3D gingival streak 225, such that the 3D gingival streak defines the boundary of the dental prosthesis. A virtual marginal gingiva 227 is added to improve the aesthetic appearance of the dental prosthesis. The virtual external gingival surface can be formed by interpolation, such as by streak-based transition and surface interpolation.

Here the surface displacement is uniform, but can also be non-uniform with a greater displacement in the alveolar ridge compared to the displacement in the 3D gingival stria, such that the gingival part is thicker in the dental part than in the limit.

The displacement in the alveolar ridge can be such that the dental prosthesis reaches the position where the teeth of the dental prosthesis are to be placed. The virtual model of the gingival part of the dental prosthesis can then be formed by a Boolean subtraction process.

In Figure 5, the virtual external gingival surface 228 of the gingival part of the dental prosthesis is formed as well as the gingival facing surface 229, so that the gingival part of the dental prosthesis can be manufactured using CAM techniques based on this virtual model. . The gingival facing surface of the dental prosthesis can be defined as an offset of the 3D digital representation of the patient's gingiva so that it is automatically configured to follow the shape of the patient's gums.

Fig. 6 shows an example of imitation in relation to a set of virtual dental models corresponding to the teeth of the dental prosthesis of a maxillary dental prosthesis.

The tooth set 660 can be selected from an electronic library containing a different tooth set number, or the operator can design the tooth set himself by defining one or more parameters for the teeth. The virtual dental models in the tooth set can be selected based on a number of parameters, such as size, shape, etc.

The patient's median line 661 is shown and a line 662 is shown perpendicular to the median line. The function of line 662 is for improved visual direction for the user. In this way, a global coordinate system is defined for the entire composite tooth set, so rotation, positioning, etc. can be controlled for the entire composite tooth set. When modeling a complete dental prosthesis, for example a full maxillary dental prosthesis, the arrangement of the virtual dental model, for example, can be determined on the left side and the arrangement of the virtual dental models is then reflected on the right side of dental prosthesis.

The individual teeth in tooth set 660 can also be individually modified. A tooth can be rotated, for example, relative to the patient's median line. Box 663 around the first molar tooth indicates that a coordinate system can be defined for each tooth so that rotation, placement, etc. can be controlled. for each individual tooth. In a computer implementation of the invention, a tooth-specific coordinate system can be displayed on the tooth indicating to the user that the program is in mode, where the individual tooth can be modified with respect to placement, e.g., rotation. , translation, etc. The teeth of the dental prosthesis can also be modified, for example, with respect to shape, for example, length, thickness, mass distribution, etc. The teeth of the dental prosthesis can be predetermined teeth where the size can be reduced, for example, devastating.

Figures 7-13 show screenshots of a computer-implemented embodiment of the invention. Figure 7 shows a 3D digital representation of the gingiva for a toothless upper jaw (maxilla). The 3D digital representation can be obtained by directly scanning the patient's gingiva using an intraoral scanner such as the 3Shape TRIOS intraoral scanner. The 3D digital representation shows the alveolar ridge 721, the groove 722 and the paddle 723 of the patient's gingiva.

Figures 8 and 9 illustrate the use of 3D digital representations of the wax surrounds when arranging the virtual dental models.

The arrangement of virtual dental models may involve the formation of an upper wax rim for the patient's upper jaw (the maxillary arch) and a lower wax rim for the patient's lower jaw (the mandibular arch). The wax rings are formed so that their interface when disposed in the patient's mouth is aligned with the patient's occlusal plane.

In some embodiments, three different scans are used when generating the combined gingiva rim-wax model 814.

Two of these scans are of the patient's maxilla and mandible so that 3D digital representations of these are obtained. The third scan is of the stack with physical models of the gums and wax rings arranged according to the patient's occlusion.

In the combined gingiva-wax rim model, the part corresponding to the maxilla and mandible of the patient in the 3D digital representation of the stack can be subtracted so that in a visualization of the combined gingiva-wax rim model 814, the 3D digital representations of the patient's mandible 828 and maxilla 825 can be viewed along with the wax surround portions 824, 827 of the 3D digital representation of the stack.

In some embodiments, the upper and lower wax rims are 3D scanned using, for example, a benchtop scanner. The obtained 3D digital representation of the upper wax rim 824 is arranged virtually relative to the 3D digital representation of the maxilla 825 thereby generating a combined gingival rim-upper wax model 826 as illustrated in Figure 8. The 3D digital representation obtained from the lower wax rim 827 is arranged relative to the 3D digital representation of the jaw 828, thereby generating a combined lower wax rim-gingiva model 829.

The relative disposition of the gingiva of the maxillary arch and the occlusal plane can be derived based on the 3D digital representation of the inferior wax rim.

The incisal edge of the anterior teeth in the mandible is located from the combined lower gingiva edge model 829, and the occlusal plane of the dental prosthesis can be determined.

For patients where the maxillary anterior teeth extend below the incisal edge of the mandibular anterior teeth, a virtual line representing the incisal edge of the maxillary anterior teeth can be defined in relation to the 3D digital representation of the lower wax rim 827 This line could also be defined on the wax rim physical model and identified on scan using texture recognition techniques. The occlusal plane can be derived purely mathematically from the combined gingiva rim model.

The combined gingiva rim-wax model can also be viewed in conjunction with virtual dental models to aid in dental models, for example by indicating to an operator where the occlusal plane is located. Based on this visualization, the position and orientation of the virtual dental models relative to the 3D digital representation of the patient's gums can be adjusted manually by an operator and / or automatically using computer-implemented algorithms.

A screenshot of such a visualization is seen in Figure 9, where the 930 virtual dental models for the dental prosthesis teeth of a maxillary dental prosthesis for the patient's upper jaw are arranged virtually relative to the 3D digital representation of the frame. 924 upper wax rim and the 3D digital representation of the maxillary arch gums 925. The 3D digital representations of the 924 upper and 927 lower wax rims are slightly transparent so that the 930 virtual dental models can be seen through the representation 3D digital representation of the superior wax rim 924. The 3D digital representation of the gingiva of the mandibular arch 928 is also visible.

When the upper wax rim is configured to have a labial surface that is shaped according to the patient's lips, virtual dental models can be arranged on the corresponding surface of the 3D digital representation of the upper wax rim, that is, such that the labial surface of the virtual dental models of the maxillary anterior teeth of the dental prosthesis is aligned with the labial surface of the upper wax rim.

Virtual dental models for a mandibular dental prosthesis can be arranged to have occlusal surfaces that are arranged according to the occlusal plane determined on the basis of the wax surrounds.

The virtual dental models corresponding to the dental prosthesis teeth of the dental prosthesis are preferably arranged spatially with respect to each other forming an anatomically correct composition of high aesthetic quality.

When a final arrangement of the virtual dental models has been identified, the next step is to determine the gingival part of the dental prosthesis.

Figure 10 illustrates how a 3D gingival streak 1032 is defined to surround virtual dental models 1030. The 3D gingival streak 1032 follows the gingival groove and ah line of the patient. The 3D gingival streak 1032 can be determined automatically using computer-implemented algorithms configured to identify the lower / upper part of the groove or by user-defined control points 1033 along which the 3D gingival streak is defined. Here the 3D gingival groove is defined to provide that the dental prosthesis does not contact the sensitive frenulum 1034.

Figure 11 shows a virtual external gingival surface of the gingival part of the dental prosthesis. The 3D gingival groove is connected to the virtual dental models 1130 in such a way that an external gingival surface or external surface 1136 of the gingival part of the dental prosthesis is generated with a gingival border or edge 1137 in the patient's groove. An anatomically correct appearance of the gingival portion can be obtained automatically, for example, by copying the shape of the corresponding surfaces in the patient's mouth or manually by the operator using computer-implemented modification tools. Modification tools can be configured to virtually add or remove material in the gingival portion of the dental prosthesis. The gingival portion here covers both the alveolar ridge and the patient's paddle 1138. In Figure 11, some structure 1146 has been added to the gingival portion at the gum-tooth lines.

Figure 12 shows how a virtual ruga structure can be added to the modeled dental prosthesis.

In Figure 12, patient ruga 1240 and incisal papilla 1241 are defined using a virtual wax knife (circled 1242 in the screenshot) provided in the 3Shape DentalDesigner.

Alternatively and / or additionally, the captured alveolar ridge and / or the patient paddle obtained by 3D digital rendering are used in the design of the dental prosthesis.

Figure 13 illustrates how the interproximal gingiva can be modified.

In Figure 13, the interproximal gingiva is modified using a virtual wax knife 1344 (circled 1344 in the screenshot), which can be performed, for example, in the 3Shape DentalDesigner.

In parts of a person's gum that cover the end of the root of the teeth, the ends of the root normally make up the gum. In the present figure, the gingival part of the dental prosthesis has already been shaped according to the shape of the root end of the teeth 1330 by adding virtual root projections or cervical projections 1345 to the corresponding sections and a marginal gingiva 1346 has been added.

This can be done either automatically by providing an offset to the outer surface based on knowledge of the cervical shape of the teeth 1330 or manually using a virtual modification tool such as the virtual wax knife.

Fig. 14 shows an example of setting teeth on the occlusal plate.

Fig. 14 schematically shows the contour of the virtual occlusal plate 1447 with the denture teeth or virtual dental models 1430 fitted to the rim of the occlusal plate.

Virtually tight means fixed, attached, held, clamped, held in virtual contact with the occlusal plate, etc. In this way, although the operator adjusts the position, orientation and / or shape of the virtual dental models, the dental models remain in the occlusion given by the occlusal plate due to the adjustment.

Figures 15-24 show an example of a workflow for digitally designing a dental prosthesis. It is understood that the different steps in the process can be performed in a different order than shown here, and that the different steps can be left out of the process or be part of a different process.

Fig. 15 shows an example of delivery of the occlusal plate.

Fig. 15a) shows an example of placement of a number of occlusal points in the wax rim that defines the occlusal plate.

The wax rim comprises the upper wax rim 1524 and the lower wax rim 1527. In the figure you can see two occlusal points 1548, 1549 arranged in the wax rim, however, typically three occlusal points will be arranged, so that in this case, the third point cannot be seen.

Fig. 15b) shows an example where the occlusal plate is shown.

Occlusal plate 1550 is determined or derived based on occlusal points 1548, 1549.

The line labeled "occlusal direction" 1551 and the other arrows in the figure indicate a virtual articulator used to set, test, and verify occlusion.

In this way, the occlusal plate can be set manually or automatically, and the occlusal plate can be adjusted manually if it was set automatically.

Fig. 16 shows an example of supplying a number of feature points in the 3D digital representation of the lower jaw and upper jaw, where the feature points determine the placement of the dental casts on the mandible (s). Characteristic points can be indicated on the wax rims 1624, 1627 by the dentist in the form of lines marked on the wax rim that indicate the midline, which will provide the central ridge points, and / or that indicate the canine lines that they will provide the canine points. In the wax surround, the smile line can also be marked by the dentist indicating the height of the anterior teeth.

Alternatively and / or additionally, the operator can virtually place the feature points in the 3D digital representation, or the feature points can be placed automatically. Feature points can also be automatically placed first and then adjusted later by the operator. Feature points can be placed based on certain placement rules. In Fig. 16 the characteristic points on the lower jaw are the retromolar pad # 1 1652, the retromolar pad # 2 1653, the first canine point 1654, the second canine point 1655 and the central ridge point 1656.

The characteristic points on the upper jaw in fig. 16 are tuberosity # 1 1657, tuberosity # 21658, first canine point 1659, second canine point 1660, and central ridge point 1661.

Fig. 17 shows an example of boundary or edge generation for the upper jaw portion of a dental prosthesis.

Fig. 17a) shows an example where the user or operator has virtually marked the contour or the 3D gingival stria 1732 of the dental prosthesis in the 3D digital representation or the 3D digital representation of the upper jaw 1725. The contour or the gingival stria 1725 3D 1732 can be generated by means of user-defined control points 1733 placed virtually on the 3D digital representation of the upper jaw or by the operator drawing a virtual line. The 1732 3D gingival contour or streak could also be generated automatically using software tools.

Fig. 17b) shows an example where the dental prosthesis 1764 is shown virtually in the 3D digital representation of the upper jaw 1725. The control points 1733 are seen for the generation of the gingival border or edge 1737. The control points can be set by operator.

Fig. 18 shows an example of boundary or edge generation for the lower jaw portion of a dental prosthesis.

Fig. 18a) shows an example where the user or operator has virtually marked the contour or 3D gingival groove 1732 of the dental prosthesis in the 3D digital representation or 3D digital representation of the lower jaw 1728. The contour or 3D gingival groove 1732 is can be generated by means of user-defined control points 1733 placed virtually on the 3D digital representation of the lower jaw or by the operator drawing a virtual line. The 3D 1732 gingival contour or streak could also be generated automatically by means of software tools.

Fig. 18b) shows an example where the dental prosthesis 1764 is shown virtually in the 3D digital representation of the lower jaw 1728. The control points 1733 are seen for the generation of the gingival border or border 1737. The control points can be set by operator.

Fig. 19 shows an example of a virtual initial arrangement of the 1930 virtual denture teeth in relation to the 3D virtual representations of the jaws 1925, 1928, and the wax rims 1924, 1927, and the 1950 occlusal plane.

Dental casts can be positioned automatically initially and the operator can then adjust the relative positions later. The dental models shown in fig. 19 may not be arranged in occlusion, aligned or arranged correctly with respect to each other, for example, if the interproximal gap between the lower centrals is too large. The operator will make sure to adjust this in later steps, either automatically or manually.

Fig. 20 shows examples of the software tools available to digitally design and adjust the dental prosthesis design.

Fig. 20a) shows an example of arc transformation. If the predefined areas 2065 for the teeth on the occlusal plate 2050 do not fit into the arc of the digital 3D representation of the gingiva 2028 and / or the digital 3D representation of the wax surround 2027 and / or the initial positions of the virtual dental models 2030, then the arch of the 2065 teeth indicated on the 2050 occlusal plate can be adjusted to fit the 2028 gingival 3D digital representation and / or the 2027 wax surround 3D digital representation and the 2030 virtual dental models, or the arch of the virtual dental models 2030 can be adjusted to fit the arch of the teeth in the occlusal plate 2050 and / or the digital 3D representation of the gingiva 2028 and / or the digital 3D representation of the wax surround 2027.

Fig. 20b) shows a wax rim reference example.

Fig. 20c) shows an example of individual transformation.

Fig. 21 shows examples of generation of the virtual gingiva of the dental prosthesis.

Fig. 21a) shows an example of the gingiva generated for the upper part of the dental prosthesis. The virtual external gingival surface 2166 can be generated by connecting the gingiva-tooth lines of the dental models 2130 with the generated gingival border, see figs. 17. In addition, material settings, such as base thickness and relief, can also be used in the generation of the virtual external gingival surface 2166.

Fig. 21b) shows an example of the gingiva generated for the lower part of the dental prosthesis. The virtual external gingival surface 2166 can be generated by connecting the gingiva-tooth lines of the dental models 2130 with the generated gingival border, see figs. 17.

In addition, material settings, such as base thickness and relief, can also be used in generating the virtual external gingival surfaces 2166 for the upper and lower part of the denture. Fig. 22 shows examples of inspection of the digital design of the dental prosthesis.

The design of the dental prosthesis can be seen from different points of view, such as from the front, see fig. 22a) and from the rear, see fig. 22b). A 2D cross section of the denture design can be made anywhere on the denture. The inserts in the lower right corners of FIG. 22a) and 22b) show a 2D cross-sectional view of the gingiva, gingival portion, and virtual dental models of the dental prosthesis as viewed in a plane that is parallel to the sagittal plane of the patient. In the 2D cross-section view, the operator can see, for example, how far into the 2066 gingiva the model 2030 teeth reach.

Fig. 23 shows an example of design features in the gingival part of the dental prosthesis.

Fig. 23a) shows the maxilla before designing the features.

Fig. 23b) shows the maxilla when virtual root overhangs or cervical overhangs 2345 have been added to the ends of the roots of virtual teeth 2330 on the gingiva 2366.

Fig. 23c) shows the mandible before designing the features.

Fig. 23b) shows the mandible when virtual root protrusions or cervical protrusions 2345 have been added to the ends of the roots of virtual teeth 2330 at the gingiva 2366.

Fig. 24 shows an example of a final design of a dental prosthesis.

The final design of dental prosthesis 2464 comprises virtual model teeth 2430 in the upper and lower jaw, and virtual gingiva 2466 comprising virtual root protrusions or cervical protrusions 2445.

The dental prosthesis design is now ready to be manufactured to produce a physical dental prosthesis for the patient's mouth.

Fig. 25 shows examples of virtual occlusal plates.

Fig. 25a) shows an example of a straight occlusal plate 2550 arranged virtually between upper and lower virtual teeth 2530.

Fig. 25b) shows an example of a curved occlusal plate 2550 arranged virtually between the upper and lower virtual teeth 2530.

Fig. 26 shows schematic examples of virtual external gingival surface design.

Fig. 26a) shows an example where the external gingival surface 2666 of the dental prosthesis is virtually designed to be rounded at the gingival edges or limits 2637. The figure also shows teeth of the virtual model 2630 and the upper or lower jaw 2625/2628 .

Fig. 26b) shows an example of adjustment of the virtual external gingival surface 2666. The adjustment is made by pulling one or more control points 2667 arranged on the virtual external gingival surface 2666. The virtual external gingival surface 2666 is adjusted in a manner that curves inwardly between patient 2625/2628 gums and 2624 tooth-gum line on 2620 dental models.

Fig. 27 shows schematic examples of the design of the upper jaw part of the dental prosthesis. Fig. 27a) shows an example of the upper part of a dental prosthesis 2764. A dent 2768 in the center of the palate or paddle area 2738 at the edge or gingival boundary 2737 of the dental prosthesis is virtually designed, since two Salivary glands exit the palate in the human mouth and the dental prosthesis should be designed so as not to cover these glands.

FIG. 27b) shows an example of a virtual design of a protrusion 2769 at the gingival edge or boundary 2737 of the palate or paddle area 2738 of the dental prosthesis. The function of the protrusion 2769 is to create a vacuum under the palate or paddle area 2738 of the upper jaw denture, whereby the top of the denture will be suctioned into the patient's own palate 2770.

Fig. 28 shows a schematic of a system according to an embodiment of the present invention. The system 2880 comprises a computing device 2881 comprising a computer-readable medium 2882 and a data processing unit 2883. The system further comprises a display unit 2886, a computer keyboard 2884, and a computer mouse 2885 for inputting data and activate virtual buttons displayed on display unit 2886. Display unit 2886 may be a computer screen. The 2881 computing device is capable of receiving a 3D digital representation of the patient's gingiva from a scanning device. 2887 scan, such as the TRIOS intraoral scanner manufactured by 3Shape A / S, or capable of receiving scan data from such a scanning device and forming a 3D digital representation of the patient's gingiva based on such scan data. The received or formed 3D digital representation can be stored on the computer-readable medium 2882 and provided to the data processing unit 2883. The data processing unit 2883 is configured to obtain virtual dental models corresponding to the teeth of the dental prosthesis. , to virtually arrange the virtual dental models in relation to the 3D digital representation of the patient's gingiva, and to generate a virtual external gingival surface of the gingival portion of the dental prosthesis using the method according to any of the embodiments. In the virtual arrangement of the virtual dental models in relation to the 3D digital representation of the patient's gingiva and the generation of a virtual external gingival surface of the gingival part of the dental prosthesis, one or more options can be presented to the operator such as as if moving one or more teeth one by one or as a group. Other options may refer to numerical values, for example, for the thickness of the gingival part of the dental prosthesis. The options can be presented on a user interface displayed on the 2886 display unit.

The system comprises a unit 2888 for transmitting the virtual 3D digital representation or a 3D model formed from it, for example, to a computer-aided manufacturing device (CAM) 2889 for manufacturing the dental restoration or to another computer system, for example , located in a milling center where the dental restoration is manufactured. The unit for transmitting the 3D virtual model can be a wired or a wireless connection.

Scanning of the patient's gums using the 2887 scanning device can be performed at a dentist while the digital design of the dental prosthesis is performed in a dental laboratory. In such cases, the 3D digital representation or a 3D model of the patient's gingiva can be provided through an Internet connection between the dentist and the dental laboratory.

Although some embodiments have been described and shown in detail, the invention is not restricted thereto, but may also be incorporated in other ways within the scope of matter defined in the following claims. In particular, it is to be understood that other embodiments can be used and structural and functional modifications can be made without departing from the scope of the present invention.

It should be emphasized that the term "comprises / comprising" when used in this specification is taken to specify the presence of indicated characteristics, integers, steps or components, but does not exclude the presence or addition of one or more other characteristics, numbers integers, steps, components or groups thereof. The characteristics of the method described above and below can be implemented in software and carried out in a data processing system or other processing means caused by the execution of computer-executable instructions. The instructions can be program code means loaded into a memory, such as RAM, from a storage medium or from another computer over a computer network. Alternatively, the described features can be implemented using hardwired circuitry instead of software or in combination with software.

Claims (4)

A method for modeling a digital design of a dental prosthesis (2464) for a patient, said dental prosthesis comprising a gingival part (2466) and a dental part comprising a set of dental prosthesis teeth (1930; 2430), where the method comprises: - obtain a 3D digital representation of the patient's gingiva (1925, 1928); - obtain virtual dental models corresponding to the teeth of the dental prosthesis (1930; 2430); - virtually arrange the virtual dental models (1930; 2430) in relation to the 3D digital representation of the patient's gingiva (1925; 1928); Y - generate a virtual external gingival surface of the gingival part (2466) of the dental prosthesis (2464), - select virtual dental models (1930; 2430) from a virtual library that includes a set of dental models (1930; 2430) for the lower jaw (1928) and a set of dental models (1930; 2430) for the mandible upper jaw (1925), where the set of dental casts for the lower jaw and the set of dental casts for the upper jaw constitute a pair that fit together and are arranged in occlusion. The method of claim 1, wherein the sets of dental models (1930; 2430) in the library are provided by 3D scanning physical dental prostheses comprising the physical versions of the dental models arranged in the sets (1930; 2430 ). The method according to claim 2, wherein the physical dentures are arranged in occlusion. The method according to claim 1, 2 or 3, wherein the dental models from different sets of dental models are combined to form the dental prosthesis.