JP2013521958A - Improving the structural stability of dental prostheses - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for improving the structural stability of a dental prosthesis.
A computer-implemented method for improving the structural stability of a dental prosthesis, wherein the method is based at least in part on the structural stability of a support point configuration using a computer system. Determining the support point configuration for a plurality of support point configurations, wherein the prosthesis includes an inner surface, an outer surface, and a peripheral edge, the peripheral edge being disposed between the inner surface and the outer surface. A plurality of discrete points are disposed on the inner surface of the prosthesis, and data for manufacturing the prosthesis is generated based at least in part on the support point configuration. To do.
[Selection] Figure 2

Description

  Embodiments herein relate to a dental prosthesis plan and an improved dental prosthesis. More particularly, the embodiments herein are directed to improving the structural stability of dental prostheses.

  In the field of dentistry, mass order production of crowns and other prostheses has become more common. During the mass production process, a dentist or other employee will design a prosthesis such as a crown and place it on the prepared tooth. Prosthetic dental prostheses supported by teeth such as copings, crowns, or bridges can cover the surface part of the teeth and are usually finished in the laboratory away from the patient's mouth, and then in the mouth by the dental practitioner Assembled in. As used herein, a prepared or prepared tooth is a tooth shaped to receive a dental prosthesis. In order to achieve a strong attachment of the dental prosthesis, it is important that the surface of the prepared tooth closely matches the mating surface of the dental prosthesis. That is, it is important that the prosthesis sits on the prepared tooth (as compared to the planned placement of the prosthesis) without much rotation and without much translational movement. However, in currently used methods of prosthesis design and manufacture, the prosthesis will typically find a support only along the prepared tooth finish line. This is because when a prosthesis is physically designed, a die spacer is usually placed on top of the prepared tooth to create a uniform gap between the prepared tooth and the physical design. Similarly, when the prosthesis is designed with CAD (Computer Aided Design), 3D, or other software, a fixed width gap between the prepared tooth and the prosthesis is required by the software, or Provided. In both physical and CAD designs, the assembled prosthesis is a support along the finishing line because there are gaps between the teeth and the prosthesis at all points except the part along the finishing line. Will only find out. When the support is found only along the tooth finish line for which the prosthesis is prepared, it can be rotated or translated with little constraint. This rotation and translation of the prosthesis contributes to the final variation in the placement of the prosthesis and is undesirable.

  Another problem with the prior art is that the gap between the prosthesis and the prepared tooth may be irregular. This gap between the prosthesis and the prepared tooth is sometimes referred to as the cement space. If the cement space is irregular then the prosthesis may not be strong and may have a shorter lifetime. A prosthesis with an irregular cement space may have a shorter life span than a prosthesis with a uniform cement space, for example.

  These and other problems are addressed by the systems, methods, apparatus, and computer readable media described herein.

  Provided herein are methods, systems, devices, and computer-readable media for manipulation, selection, and planning of dental prostheses. This summary is not intended to limit the invention in any way, but is provided instead to summarize a few embodiments.

  Embodiments herein include systems and methods for improving the structural stability of dental prostheses. Certain embodiments include methods, systems, and computer-readable media for improving the structural stability of dental prostheses, and prostheses made thereby. Embodiments can include determining a support point configuration for the prosthesis based at least in part on the structural stability of the support point configuration. The prosthesis can include an inner surface, an outer surface, and a peripheral edge, the peripheral edge being disposed between the inner surface and the outer surface. The support point configuration can include a plurality of discrete points, the plurality of discrete points are disposed on the inner surface of the prosthesis, and data for manufacturing the prosthesis is generated based at least in part on the support point configuration Can be done. The prosthesis can be a coping, a crown, a cover, a bridge, and the like.

  In certain embodiments, a dental prosthesis can include a body that includes an inner surface, an outer surface, and a peripheral edge, the outer surface being generally disposed on an outwardly facing portion of the prosthesis, the inner surface Is generally designed to fit a prepared tooth, with a perimeter located between the inner and outer surfaces. The prosthesis can also include a support point configuration having a plurality of support points, the plurality of support points being non-uniformly disposed on the inner surface away from the periphery.

  In some embodiments, determining the support point configuration for the prosthesis uses a computer system to determine at least two candidate support point configurations, each candidate support point configuration having a plurality of discrete points. Using a computer system to determine a structural stability assessment for each of the candidate support point configurations; and at least two candidates as support point configurations based at least in part on at least two structural stability assessments Selecting one of the support point configurations. The support point can be located away from the top and / or periphery of the prosthesis.

  In some implementations, determining candidate support point configurations includes performing the Wang algorithm, performing a modification thereof, or generating a configuration of random seed positions as expected support point locations, and the support points at those locations are Finding a configuration of support point locations that has improved structural stability over the structural stability of the predicted support configuration of the previous iteration. Any other suitable algorithm can also be used. The number of candidate support point configurations to consider can be pre-defined, or additional candidate support point configurations have a structural stability assessment for at least one candidate support point configuration above a predetermined threshold Can be determined up to. The structural stability assessment can be calculated based on the root mean square of the variation in the position of the inner surface of the prosthesis across multiple simulated assemblies or based on the worst case or best case calculation.

  Many other embodiments are described throughout this specification.

  For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention are described herein. Of course, it is to be understood that not necessarily all such objectives or advantages need be achieved by any particular embodiment. Thus, for example, those skilled in the art will recognize one advantage or group of teachings or suggestions herein without necessarily achieving the other objects or advantages that the invention can be taught or suggested herein. It will be appreciated that the invention can be implemented or carried out in a manner that achieves or optimizes the advantages.

  All of these embodiments are intended to be within the scope of the invention disclosed herein. These and other embodiments will be readily apparent to those skilled in the art from the following detailed description, taken with reference to the accompanying drawings, and the present invention will be described in any particular disclosed embodiment (s). Is not limited.

FIG. 1 is a flowchart showing the life cycle of a dental prosthesis.

FIG. 2 shows a flow diagram for a method for dental data planning.

FIG. 3 is a first schematic view of a prosthesis having a hollow portion depicted from below.

FIG. 4 is a second schematic view of a prosthesis having a hollow portion, depicted from below.

FIG. 5 is a diagram depicting three different regions within the inner surface of the hollow portion of the prosthesis.

FIG. 6 depicts various shapes and dimensions of the support points.

FIG. 7 shows a system for improving the structural stability of a dental prosthesis.

Dental Prosthesis As shown in FIG. 1, there are many steps between patient examination and prosthesis manufacture and assembly. Generally, the dentist examines the patient and determines what type of prosthesis is needed. This is shown at step 110 of the treatment life cycle 100 of FIG. The physician can polish or otherwise prepare the teeth so that the teeth can receive and support prostheses such as crowns, copings, or bridges. Step 110 may include making a prepared dental plaster model. Step 110 can also include taking a physical or virtual impression with a scanner. After the examination and any preparation is completed, a 3D model of the prepared tooth can be obtained. The prepared tooth 3D model could be obtained directly from the prepared tooth scan if the tooth was scanned using a 3D scanner. Alternatively, if a dental physical impression or model has been created, then at step 120 the tooth impression or model can be scanned to obtain a 3D model. The output of a prepared tooth direct scan or tooth impression or model scan will typically be a 3D model such as a point cloud or a triangulated mesh surface model. The prosthesis is designed based on the scanned model of the teeth prepared in step. Prosthetic design can be accomplished by any employee using various CAD, 3D modeling, NobelProcera, and / or other types of software. Based on the design of the prosthesis made at step 130, the prosthesis is manufactured at step 140. Manufacturing can take many different forms. For example, for coping, the coping itself can be made and sent to a dental technician, who can then apply a porcelain layer over the teeth. In some embodiments, when making an entire crown, the entire crown including the surface can be made. The top or other colored layer can later be applied by a technician or automatically applied as part of the manufacturing process. After the prosthesis has been manufactured in step 140, it is sent to the attendant for assembly in the patient's mouth as part of step 150. As used herein, the term assembly can indicate that the practitioner places the prosthesis on the prepared tooth. One skilled in the art will recognize that other treatment lifecycles exist and can be used with the embodiments herein.

  In certain embodiments, the prosthesis can have an inner surface, an outer surface, and a periphery. The outer surface may be a portion facing outward from the prosthesis. For example, for a crown, the outer surface can be the portion of the prosthesis that can be seen once the crown is assembled. The inner surface can be the part of the prosthesis that is designed to fit over the prepared tooth. In some embodiments, the support points are distributed on the inner surface. The peripheral edge can be an interface disposed between the inner surface and the outer surface.

  Various embodiments herein are also filed on March 12, 2010 and claim the priority of PCT / EP08 / 07469 “To plan medical practice and generate data related to said medical practice” Can be used as part of the determination of structural stability or sensitivity for the entire assembly process as described in US patent application Ser. No. 12 / 678,137, entitled “Methods and Systems of”. Said application is hereby incorporated by reference in its entirety for all purposes.

Structural Stability for Dental Prostheses Numerous embodiments herein provide the ability to improve structural stability for a designed prosthesis. As used herein, structural stability is a measure of how close a prosthesis is to the designed or desired arrangement once the prosthesis is assembled. In other words, structural stability is a property of a crown or other prosthesis that allows it to be assembled with minimal variation in position and orientation. Structural stability can be assessed by simulating multiple prosthetic assemblies and measuring how far the assemblies are “distant” with respect to the designed or desired arrangement. In the design, it may be important to minimize the peripheral openings and gaps between the prepared tooth and the inner surface of the prosthesis while still providing sufficient space for the cement, particularly a uniform cement space. As indicated above, a uniform or nearly uniform cement base may be desirable to improve the structural stability of the prosthesis. Structural stability is an important aspect of design. This is because the structural stability design also minimizes peripheral openings and gaps across many possible assemblies. When a prosthesis is designed for a prepared tooth for a patient, there will typically be a gap between the prosthesis and the prepared tooth. This gap will typically be filled with cement to secure the prosthesis to the prepared tooth. The space between the prepared tooth and the prosthesis is sometimes referred to as the “cement space”. The cement space can be any thickness or width, such as 40-60 micrometers.

  The position of the prosthesis with respect to the prepared tooth will be defined by the assembly of the prosthesis on the prepared tooth. Traditionally, the prosthesis is placed on the prepared tooth and the contact point between the prosthesis and the prepared tooth will be along the finishing line of the prepared tooth bottom. It is difficult to accurately predict which points along or near the prepared tooth finish line are in contact with the prosthesis. Using traditional methods, the contact points along the finishing line can be approximately coplanar with a very narrow area near the finishing line, or all within that area. In part, the contact points along the finishing line are substantially coplanar when using traditional methods, so when the prosthesis is inserted over the prepared tooth, it will be against the desired placement. Can be inserted in a vertically and / or horizontally rotated and / or translated manner. Various embodiments herein provide support points or contact points on the prosthesis so that the prosthesis can be guided to the appropriate position across a wide variety of prosthesis assemblies on the teeth. Helping to fix this problem by making a decision.

Improved structural stability In order to improve the structural stability of the prosthesis, support points can be added to the inner surface of the prosthesis. These support points provide a contact point between the prosthesis and the prepared tooth. Support points can be defined over several iterations of the algorithm of selecting candidate support point configurations for each iteration based on the seed value. In one embodiment, the structural stability for candidate support point configurations is compared for all iterations, and one of them is selected for use with the prosthesis. This selected support point configuration can then be used in the production of prostheses to produce a prosthesis that is more structurally stable during the assembly process. In general, each candidate support point configuration will include a plurality of support points on the inner surface of the prosthesis. In some embodiments, the plurality of support points will be distributed unevenly. Further details in seeding and selection during candidate support point construction are further described below with respect to various embodiments.

  FIG. 2 shows a flow diagram for a method for dental data planning. The method 200 includes a number of steps that can be performed in various orders. Some steps can be performed more than once, a group of steps can be performed more than once, some steps can be omitted, and the steps are performed in a different order Can do. In some embodiments, the process is performed as shown in FIG.

  In step 210, candidate support point configurations are determined. In some implementations, step 210 can include determining the position of the support points in the candidate support point configuration. In certain embodiments, step 210 can also include determining the size and / or shape of the support point. In still other embodiments, the size and / or shape of the support point is determined either as part of another step of method 200 either before or after step 210 or at a step not shown in method 200. Can do. Considerations regarding the size and shape of the support points are further described below.

  The position of the support point can be determined using any suitable algorithm. For example, in certain embodiments, seed points can be distributed around the inner surface or hollow portion of a prosthesis that is mounted on a prepared tooth. Of those points, the position of their seed points can be moved and / or redistributed, and the effect on the structural stability of the prosthesis can be checked after their movement or redistribution. If the new location of the support point gives a better structural stability rating, then the new location is adopted. In one embodiment, the position of one support point is moved at a time and the structural stability assessment is compared after each individual move. Point movement can be stopped if no further increase in structural stability is achieved by moving the point. Once the point movement is stopped, the position of the support point can be a candidate support point configuration.

  In one embodiment, in step 210, the candidate support point configuration is the algorithm of Wang et al., Optimizing Fixture Layout in a Point-Set Domain, IEEE Transactions on Robotics and Automation, Vol. 17, no. 3, June 2001. Can be determined by: In general, this algorithm (referred to herein as the “Wang algorithm”) uses seed points at various locations on the surface, and these points are used to minimize the amount of translation and rotation that may occur during assembly. Optimize the position. Details of the algorithm are given here. 3 and 4 using the Wang algorithm, each of which is a schematic view of a prosthesis 300 or 400 having a hollow portion 310 or 410 designed to be mounted on a prepared tooth. , This method will first select a set of random points 321-326 located around the inside of the hollow portion 310 of the prosthesis 300. After executing the Wang algorithm on seed points 321-326, candidate support point configurations are determined, as indicated by support points 421-426 in FIG. In some embodiments, the candidate support point configuration will have a non-uniform distribution.

  The seed points used in Wang or any other algorithm can be distributed randomly across the inner surface of the hollow portion of the crown or other prosthesis. In some embodiments, the seed points are distributed over a smaller portion of the inner surface of the hollow portion of the prosthesis. Support points distributed over a smaller portion of the entire surface area can reduce the range of support point configurations and thus eliminate some structural stability solutions, but with manufacturing limitations or installation considerations. It may be preferable for various reasons. For example, support points near the periphery will be removed from the prosthesis and prepared tooth seal. Also, having a support point on the top, ceiling, or cap of the inner surface can cause the prosthesis to rock or vibrate on the prepared tooth. As another example, the size of the support point may also affect how close the support point can be at the periphery of the prosthesis. For example, if the support point protrudes 0.1 mm and the desired thickness of the cement space is 0.1 mm, then it may be important to keep the support point at least 0.1 mm away from the periphery.

  The strength of the material used to make the prosthesis can also help define where the support points can and cannot be placed. If the prosthesis is, for example, ceramic, then the support point should not be placed too thin so that the prosthesis cannot be crushed. This can mean that the prosthesis places the support point away from the thin periphery or any other region. Thus, in some embodiments, the seed point is the base of the prosthesis near the periphery and / or because the support point is kept away from the periphery or to avoid placing the support point where the prosthesis is too thin. Or it can be distributed over the area of the inner surface of the hollow part of the prosthesis that excludes the head of the prosthesis furthest from the periphery. This is illustrated in FIG. FIG. 5 is a diagram depicting three different regions within the inner surface of the hollow portion of the prosthesis. Surface 510 is the region of the interior hollow portion of the prosthesis near the bottom of the prosthesis near the periphery. Surface 520 represents the entire inner surface of the prosthesis. Surface 530 is a region of the inner surface of the prosthesis that excludes the area near the top, ceiling, cap, or zenith of the inner surface of the prosthesis, which may be referred to as the intermediate region surface 530. As shown, in certain embodiments, seed support points can be distributed around the entire inner surface 520 of the prosthesis or around a subset of the inner surface of the prosthesis, such as the intermediate region surface 530. . Further, in some embodiments, the results of Wang or any other algorithm, such as candidate support point configurations, may also be on a subset of the interior surface of the prosthesis, such as the region indicated by surface 530 in FIG. It can be limited to a certain support point.

  In some implementations, candidate support point configurations can include non-uniform distribution of support points. The non-uniform support point configuration can take many forms. For example, if there are three support points, the plane containing the three support points can be non-perpendicular to the longitudinal axis of the prosthesis. If there are more than four support points, they may not all be contained within a single plane. In certain embodiments, each support point can be at a different height relative to the base of the prosthesis. The support points can also be distributed unevenly around the circumference of the prosthesis. For example, the angle along the perimeter between a pair of support points can be different from the angle along the perimeter between any other pair of support points.

  The top of the inner surface of the prosthesis can be defined in a number of ways. For some prostheses, the surface of the inner surface of the prosthesis can be substantially vertical, while the top can have a substantially horizontal surface. By looking at the inner surface of the prosthesis, it is possible to define the apex and determine where a “shoulder” exists between the horizontal portion of the inner surface and the generally vertical portion of the inner surface. A substantially horizontal portion of the inner surface can be defined as the top. The top of the inner surface can also be defined in terms of a percentage distance from the top or highest point on the inner surface. For example, the top can be defined as up to about 2%, 5%, 6%, 10%, 30%, or any other suitable percentage of the inner surface. Similarly, when support points are distributed away from the periphery, the minimum distance from the edge where any support point is located is at least about 2%, 5%, 6% of the inner surface away from the periphery. It can be 10%, 30%, or any other suitable percentage.

  In some implementations, the plurality of seed points used to determine the candidate support point configuration can be three or more. For example, six support points can be used to control six degrees of freedom, such as rotation and translation, where the prosthesis can be changed from the desired attachment location during the attachment process. In one embodiment, the six degrees of freedom can be in the X, Y, and Z directions, and pitch, roll, and yaw. In certain embodiments, more support points can be added at iterations to improve structural stability. For example, if three seed points were initially set, then one, two, three, or more seed points could be added to improve structural stability .

  Typically, regardless of the number of seed points initially used, at least three discrete support points will be used in the candidate support point configuration to maintain structural stability. More than one support point can be co-located with another support point, thereby effectively reducing the total number of support points by one. When this happens, fewer than six support points can be used on the inner surface of the prosthesis. In different embodiments, any number of support points can be used. In some embodiments, if two or more support points can be co-located, but if the freedom in all directions is to be controlled, then any candidate configuration of support points There will be more than two discrete support points on the inner surface of the prosthesis.

  Other algorithms for determining candidate support point configurations can be used in step 210. Such other algorithms are known to those skilled in the art.

  After candidate support points are determined at step 210, a structural stability assessment is determined for that configuration of support points at step 220. In certain embodiments, the structural stability assessment can be determined based on the modeled inner surface of the prosthesis. For example, the inner surface of the prosthesis can be modeled using a triangular mesh. Mesh triangles will share a node, and each triangle is defined by three nodes. Determining the structural stability assessment for the candidate support points includes simulating the assembly or attachment process of the prosthesis onto the prepared teeth, and the nominal or designed placement of the prosthesis and the prosthesis Determining an error metric for variation between the simulated or evaluated placement of the object. Such a criterion is that the nodal points on the triangular mesh representing the inner surface of the prosthesis when the inner surfaces of the prosthesis are compared to the nominal, planned or desired position of those nodal points, or It can be the root mean square of the changed location. The mesh is not depicted in FIGS. The root mean square or other criteria can be determined over multiple simulations of the installation or assembly process. For example, 10,000 simulations of the assembly or attachment process, or any number of simulations can be used in the calculation of structural stability measurements. Other criteria can also be used. For example, a criterion calculated based on the standard deviation of the worst case or best case scenario can be used. For example, if it is desired to reduce the impact of the worst case scenario potentially possible, then the structural stability criterion may be chosen to vary by some number of worst case scenario standard deviations. By choosing a candidate support point configuration with the most desirable worst case scenario criteria, the worst case scenario for prosthesis assembly or attachment should be minimized or reduced as well.

  After structural stability assessments for those candidate support point configurations are determined at step 220, then at step 230, a determination is made as to whether more candidate support point configurations should be determined. In some embodiments, a predetermined number of candidate support point configurations are generated (eg, 5 or 10). In one embodiment, new candidate support point configurations are generated until the configuration meets a threshold structure stability assessment or until a new candidate support point configuration exceeds a certain threshold relative to the previous assessment.

  If more candidate support point configurations will not be determined, then step 240 is performed. However, if more candidate support point configurations are to be determined, then steps 210 and 220 are performed again to determine another configuration of support points. In particular, the new configuration of random seed points is used in step 210 to determine a new candidate support point configuration. Structural stability calculations are then performed for the newly determined candidate support point configuration at step 220.

  At step 240, the support point configuration is selected from among all candidate support point configurations. Selection among candidate support points may include, in one embodiment, selecting the one with the “best” structural stability rating. If, for example, the root mean square of the position of the nodal point on the inner surface of the prosthesis hollow as determined in step 220 is used to select which candidate support point configuration should be used. The selection will then be based on which candidate support point configuration has the lowest root mean square. In some embodiments, the candidate support point configuration can be non-uniform, so the selected support point configuration can also be non-uniform.

  After the support point configuration is selected at step 240, then at step 250, data for the dental prosthesis is generated based at least in part on the selected support point configuration. In certain embodiments, generating data for a dental prosthesis includes generating an STL or SDL model or surface model for a triangular mesh representing the prosthesis, including an internal cavity with a selected configuration of support points. Can include exporting. Surface model generation can be done when support points are defined during the software dental design process. The arrangement of selected configurations of support points can alternatively be included in a separate data file from the prosthesis surface. In one embodiment, the data can be generated during a CAM (computer aided manufacturing) preparation process of the prosthesis. The generated data can include a milling path for milling the inner surface and the selected support point configuration. One skilled in the art will recognize that there are many ways in which data can be exported and used in subsequent CAD modeling, CAM modeling, or manufacturing. All those various ways in which a model can be exported and subsequently used are considered to be within the scope and spirit of the embodiments herein.

  Embodiments herein can include any type of prosthesis, including prostheses that include two or more inner surface regions. For example, in the case of a bridge, it can be a number of prepared teeth on which the bridge is mounted. The prosthesis can include an inner surface for each prepared tooth. If the bridge is mounted on, for example, three prepared teeth, there can be three inner surfaces on the bridge, and the support point is for each prepared tooth using the embodiments herein. Can be determined. Additionally, the prosthesis need not include a contained cap as shown in the embodiment shown in the figures. In some embodiments, a prosthesis, such as a cover or laminate, may not include a hollow portion, but instead is designed to mate with a tooth, but has an inner surface that forms only a partial covering of the tooth. Can do. Embodiments herein include determining the configuration of support points on the overlay, laminate, or any other prosthesis.

In addition to determining the position of the support point candidate support point and the selected support point configuration determined by method 200, a determination can also be made regarding the size and / or shape of the support point. This is described above with respect to step 210. As mentioned above, determining the size and / or shape of the support points can be done as part of step 210, or it is part of another step performed before or after step 210. be able to. In certain embodiments, support points can be defined based at least in part on their manufacturing tolerances, such as milling accuracy or any other suitable factor. Manufacturing tolerances can be different at different manufacturing locations. Thus, knowing the manufacturing location can help define the size and / or shape of the support points.

  Another factor that may affect the size and / or shape of the support point may be the desired thickness of the cement space between the prosthesis and the prepared tooth. For example, if a special width of the cement space is desired, then the support point may extend from the inner surface of the prosthesis to maintain that special width of the cement space between the prepared tooth and the prosthesis. Can be designed to protrude by a certain width. As explained above, having a uniform width for the cement space can improve the strength and structural stability of the prosthesis.

  One option for the shape of the support point is a cap such as a sphere or spheroid cap. The support point can extend from the inner surface of the prosthesis as a hemisphere or a spherical cap smaller than the hemisphere. Considering the example of FIG. 6, it shows various support points 610-640 on the surface 600. Some embodiments will use a single type of support point (eg, the same dimensions and shape), while other embodiments will use multiple types of support points. The support points can be designed to more evenly distribute the force and friction between the inner surface of the prosthesis, such as the crown, and the prepared tooth. In some embodiments, a support point having a shape close to a spherical cap, such as support points 610-630, may be used. In general, when a sphere cap support point is used, at most, only half of the sphere will extend from the surface 600. The support point 610 extends from the surface 600 as a substantially hemisphere. Support point 620 extends from surface 600 as a spherical cap smaller than a hemisphere. Support point 630 is a sphere larger than 610 or 620 and extends from surface 600 as a sphere cap smaller than a hemisphere. Support point 640 is not a sphere, but instead is a different type of spheroid. Support point 640 is just one of many examples of the different types of support points that can be used in various embodiments herein.

  As mentioned above, as a further consideration of the shape of the support point, the support point can have the shape of a spherical cap. The radius of the cap of the sphere that makes the support point can be 0.05 mm to 2 mm, or any other suitable dimension. In certain embodiments, the larger the radius of the sphere, the fewer spheres are used to create the support points. The radius of the support point can be defined based on manufacturing capabilities and / or design considerations. For example, if the prosthesis is milled, the size of the milling tool may constrain the size of the support point.

  As mentioned above, the method 200 can include different steps, and the steps included can be performed in different orders. For example, in one embodiment, the structural stability assessment determination step 220 for each candidate support point configuration can be performed once all candidate support point configurations have been determined by iteration over steps 210 and 230. . Further, step 220 can be implemented as part of the determination of the selected support point configuration made in step 240.

  As an additional step, although not depicted in FIG. 2, corresponding to step 140 of FIG. 1, a prosthesis can be generated based at least on the data generated in step 250. In some embodiments, the prosthesis can be milled. In other embodiments, the prosthesis can be made based on a mold made based on the data generated in step 250 of FIG. Other suitable methods and techniques for making a prosthesis based on the data will be recognized by those skilled in the art. Further, as mentioned in the description of FIG. 1, a prosthesis generated based on the data from step 250 can be implanted in the patient as shown in step 150 of FIG. A manufactured prosthesis, such as a crown, bridge, or coping, can have an inner surface that defines a hollow in the prosthesis. As mentioned above, the inner surface can have an intermediate region. In certain embodiments, the manufactured prosthesis can have one or more of its support points along the intermediate region. As mentioned above, having a support point along the intermediate region can improve the structural stability of the prosthesis.

Exemplary System FIG. 7 illustrates one embodiment of a system 700 for improving the structural stability of a dental prosthesis. The system 700 can include one or more computers 710 coupled to one or more displays 720 and one or more input devices 730. Various embodiments may be implemented on a system 700 that includes only one or more computers 710 without interaction with an operator 740. In certain embodiments, when there is an interaction with an operator 740 that can be a dentist, dental technician, or other person, the operator 740 can be a keyboard and / or a mouse. By operating the input device 730, the system 700 can be used to plan data for a dental prosthesis. In some embodiments, the operator 740 can view the image on the display 720 while working on the dental design. Display 720 can include one or more display areas or portions of a display, each of which displays a different aspect of the dental design. The display 720 can also have an area that allows the operator 740 to enter patient (s) data, which allows the operator to input data using an input device such as a keyboard and mouse. Can be entered.

  In various implementations, the computer 710 can include one or more processors, one or more memories, and / or one or more communication mechanisms. In some implementations, two or more computers 710 can be used to perform the modules, methods, and processes described herein. Additionally, the modules and processes herein can be executed on one or more processors, respectively, on one or more computers, or the modules herein can be executed on dedicated hardware. be able to. Input device 730 may include one or more keyboards (for one or both hands), a mouse, a touch screen, voice commands and associated hardware, gesture recognition, or any other that provides communication between operator 740 and computer 710. Means can be included. Communication in the various elements of system 700 can be USB, VGA cable, coaxial cable, fire wire, serial cable, parallel cable, SCSI cable, IDE cable, SATA cable, 802.11 or Bluetooth based wireless, or any It can be achieved through any suitable coupling, including other wired or wireless connection (s). One or more elements in system 700 can also be combined in a single unit. In certain embodiments, all electronic elements of system 700 are contained within a single physical unit.

  Display 720 can be a 2D or 3D display and can be based on any technology such as LCD, CRT, plasma, projection, and the like.

  The processes, computer readable media, and systems described herein can be implemented on or associated with various types of hardware, such as computer systems. Within the computer, the system can include a bus or other communication mechanism for communicating information, and a processor coupled to the bus for processing information. The computer system can have a main memory such as a random access memory or other dynamic storage device coupled to the bus. Main memory can be used to store instructions and temporary numeric variables. The computer system may also include a read only memory or other static storage device coupled to the bus for storing static information and instructions. The computer system can also be coupled to a display such as a CRT or LCD monitor. The input device can also be coupled to a computer system. These input devices can include a mouse, trackball, or cursor-oriented keys. The computer system described herein may include a computer 710, a display 720, and / or an input device 730. Each computer system can be implemented using one or more physical computers or computer systems or portions thereof. The instructions executed by the computer system can also be read from a computer-readable medium. The computer readable medium can be a CD, DVD, optical or magnetic disk, laser disk, carrier wave, or any other medium readable by a computer system. In some embodiments, the wire connection circuit can be used in place of or in combination with software instructions executed by the processor.

  As will be apparent, the features and attributes of the particular embodiments disclosed above can be combined in different ways to form additional embodiments, all of which are within the scope of the invention. .

  In particular, the conditional languages used herein, such as “can”, “could”, “high”, “may”, “e.g.”, etc., unless otherwise stated or within the context in which they were used. Unless otherwise understood, it is generally intended that some embodiments include certain features, elements and / or conditions, but other embodiments do not. Accordingly, such conditional languages generally require that features, elements and / or states be in any way necessary for one or more embodiments, or that one or more embodiments are in accordance with the opinion or inspiration of the author or Rather, it is intended to mean that these features, elements and / or conditions necessarily include logic to determine whether they are included or should be implemented in any particular embodiment. do not do.

  Any process description, element, or block in the flowcharts described herein and / or shown in the accompanying drawings can be executed to perform one or more specific logic functions or steps in the method. It should be understood as a potential representation of a module, segment, or portion of code that contains such instructions. Alternative implementations are included within the scope of the embodiments described herein, where the elements or functions are substantially simultaneous, depending on the functionality involved, as will be appreciated by those skilled in the art. Or deleted from what is shown or described, including the reverse order, and can be performed out of that order.

  All the methods and steps described above are embodied in and completely via software code modules executed by one or more general purpose computers or processors, such as those computer systems described above. Can be automated. The code modules can be stored in any type of computer readable medium or other computer storage device. Some or all of the methods can alternatively be embodied in dedicated computer hardware.

  It should be emphasized that many variations and modifications can be made to the above-described embodiments, and those elements should be understood as being in other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.

Claims (25)

In a computer implemented method for improving the structural stability of a dental prosthesis,
The method includes using a computer system to determine the support point configuration for the prosthesis based at least in part on the structural stability of the support point configuration;
The prosthesis includes an inner surface, an outer surface, and a peripheral edge;
The peripheral edge is disposed between the inner surface and the outer surface;
The support point configuration includes a plurality of discrete points, the plurality of discrete points are disposed on the inner surface of the prosthesis,
Data for manufacturing a prosthesis is generated based at least in part on the support point configuration;
A method characterized by that. Determining the support point configuration for a prosthesis;
Using a computer system to determine at least two candidate support point configurations, each candidate support point configuration including a plurality of discrete points;
Determining a structural stability assessment for each of said candidate support point configurations using a computer system; and at least two candidates as said support point configurations based at least in part on at least two structural stability assessments Selecting one of the support point configurations;
The method of claim 1, comprising:   Determining the candidate support point configuration generates a random seed location configuration as an expected support point location, and iteratively moves the expected support point location so that the support points at those locations are prior iterations. 3. The method of claim 2, comprising finding a configuration of support point locations that has improved structural stability over the structural stability of the predicted support point configuration.   The method of claim 2, wherein determining a candidate support point configuration comprises performing a Wang algorithm.   5. A method according to any of claims 1 to 4, wherein generating data for manufacturing includes generating a shape of a support point close to a cap protruding from the inner surface of the prosthesis.   6. A method according to any preceding claim, wherein generating data for manufacturing includes determining the size and shape of the support points based at least in part on manufacturing tolerances.   7. A method according to any preceding claim, wherein generating data for manufacturing comprises selecting a prosthesis from the group consisting of a coping, a crown, or a bridge.   Determining the support point configuration for the prosthesis includes determining more than two candidate support point configurations, wherein the number of determined candidate support point configurations is predefined. The method according to claim 2.   Determining the support point configuration for a prosthesis includes determining more than two candidate support point configurations, wherein additional candidate support point configurations are structurally stable for at least one of the candidate support point configurations. 9. A method according to any of claims 2 to 4 or 8, characterized in that the sex assessment is determined until it is above a predefined threshold.   Determining the support point configuration for the prosthesis, at least in part, the position of the inner surface of the prosthesis across multiple simulated assemblies as compared to the nominal position of the inner surface of the prosthesis 10. A method according to any of claims 2 to 4 or 8 to 9, comprising calculating a structural stability assessment based on the root mean square of the fluctuations.   Determining the support point configuration for the prosthesis is based, at least in part, on a worst case or best case calculation of variations in the position of the inner surface of the prosthesis across a number of simulated assemblies. 10. A method according to any of claims 2 to 4 or 8 to 9, comprising calculating a structural stability assessment.   12. The data generation for manufacturing includes generating data for a plurality of discrete support points including three or more discrete support points. the method of.   Generating data for manufacturing generates data for at least one support point in the support point configuration such that at least one support point is located away from the top of the inner surface of the prosthesis. The method according to claim 1, comprising:   14. A method according to any of claims 1 to 13, wherein generating data for manufacturing includes generating data including an inner surface and a surface model for the support point configuration.   15. The method of any of claims 1-14, wherein generating data for manufacturing includes generating data for a milling path for milling an inner surface and the support point configuration. The method described in 1. In a dental prosthesis comprising a body including an inner surface, an outer surface, and a periphery,
The outer surface is generally located on the outwardly facing portion of the prosthesis, the inner surface is generally designed to be attached to a prepared tooth, and the peripheral edge is the inner surface Between the outer surface and the
The prosthesis also includes a support point configuration, wherein the support point configuration includes a plurality of support points, the plurality of support points being spaced unevenly on the inner surface away from the periphery.
A dental prosthesis characterized by that.   The dental prosthesis according to claim 16, wherein the plurality of support points are close to a shape of a spherical cap protruding from the inner surface of the prosthesis.   18. Dental prosthesis according to any of claims 16 to 17, characterized in that the dimensions and shapes of the plurality of support points are determined at least in part based on manufacturing tolerances.   The dental prosthesis according to any one of claims 16 to 18, wherein the prosthesis is selected from the group consisting of a coping, a crown, or a bridge.   The dental prosthesis according to any one of claims 16 to 19, wherein the plurality of support points include three or more discrete support points.   The dental prosthesis according to any one of claims 16 to 20, wherein the inner surface of the prosthesis further includes a top, and at least one of the plurality of support points is disposed away from the top of the inner surface. .   The dental prosthesis according to any of claims 16 to 21, wherein the support point configuration is determined based on the structural stability of the support point configuration. 23. Dental prosthesis according to any of claims 16 to 22, characterized in that the support point configuration for the prosthesis is determined based at least in part on the following:
Determining at least two candidate support point configurations, wherein each of the at least two candidate support point configurations includes a plurality of discrete points;
Determining a structural stability assessment for each of the at least two candidate support point configurations; and at least partially out of the at least two candidate support point configurations based on the at least two structural stability assessments. To choose. In a system for improving the structural stability of a dental prosthesis,
The system includes one or more computers, each of the computers including one or more processors and memory;
The computer is configured to determine a support point configuration for the prosthesis based at least in part on the structural stability of the support point configuration;
The prosthesis includes an inner surface, an outer surface, and a peripheral edge, the peripheral edge being disposed between the inner surface and the outer surface;
The support point configuration includes a plurality of discrete points, the plurality of discrete points are disposed on the inner surface of the prosthesis,
Data for manufacturing a prosthesis is generated based at least in part on the support point configuration;
A system characterized by that. A computer readable medium for improving the structural stability of a dental prosthesis, the computer readable medium comprising instructions, operable to execute the instructions on a computer system;
Performing a method comprising determining a support point configuration for a prosthesis based at least in part on the structural stability of the support point configuration when the instructions are executed on a computer system;
The prosthesis includes an inner surface, an outer surface, and a peripheral edge, the peripheral edge being disposed between the inner surface and the outer surface;
The support point configuration includes a plurality of discrete points, the plurality of discrete points are disposed on the inner surface of the prosthesis,
Data for manufacturing a prosthesis is generated based at least in part on the support point configuration;
A computer-readable medium characterized by:

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