WO2017041148A1

WO2017041148A1 - Method for obtaining personalized surgical guides used in incision-free surgery for dental implants

Info

Publication number: WO2017041148A1
Application number: PCT/BR2015/050143
Authority: WO
Inventors: César Fernando OLESKOVICZ
Original assignee: Odontologia Caesar Ltda.
Priority date: 2015-09-10
Filing date: 2015-09-10
Publication date: 2017-03-16

Abstract

The present invention relates to a method for obtaining surgical guides for odontological implants. The method begins with the production of a mould of the patient's arch; next, the referral of the patient and of this mould for separate production of two CT images, mapping the entire bone structure of the patient's face and dentition; the digitized images from the CT examination are recorded in an electronic file that will be used by three-dimensional software, the objective of which is, by means of the analysis of the three-dimensional images obtained (mapping of the patient's face and image taken from the mould of the patient's dental arch), to produce the surgical guide; using the optimum surgical plan found, a surgical guide is created that will be perfectly adapted to the patient's mouth, same comprising the devices that will guide the fastening of the osseointegration pins. With the surgical guide in position, the implants are fastened without the need for any incision, since the screws are inserted in a small bore in the gum.

Description

PROCEDURE FOR OBTAINING CUSTOM SURGICAL GUIDELINES USED FOR CUT SURGERY FOR DENTAL IMPLANTS

DESCRIPTION OF TECHNICAL STATE

[001] The present invention relates to a process for obtaining custom guides used in blunt surgery for dental implants. Blunt surgery is considered an evolution to conventional surgeries, which are performed with incisions through gingival cuts for the purpose of exposure of the dental arch bone for the implant application. This conventional technique invariably causes bleeding, aggressive interventions, and especially psychological trauma in patients undergoing dental implant procedures.

Dental medical literature has shown that dental implants are characterized by the installation of a screw, usually titanium (Ti), to the shape of the root of the tooth that will support the type of prosthesis, similar to missing teeth. that will be deployed. Such a screw is installed in the mandible (lower) or maxilla (upper) covered by gingival tissue.

In conventional surgeries, a local anesthetic is usually performed, and then the bone is exposed by cutting the gum and detaching all the surrounding soft tissue to initiate the preparation of the so-called bone bed through a progressive sequence of drills under saline irrigation. This type of procedure can, in some situations, cause trauma, including psychological, and intraoperative complications bringing complications to the surgical procedure, such as: hemorrhage, paraesthesia (tingling sensation), perforation of the roots of the teeth, infections, bone fractures, bruises, edema, among others. The risks of the occurrence of these events, when informed to the patient, may even culminate with the postponement or withdrawal of the intended surgical procedure.

In the conventional form of this type of surgical intervention, one has that this technique was supported, in the first place, by the imaging exams that were had at the very beginning. These imaging exams were consistent with two-dimensional panoramic radiographs that allowed the dentist to identify the best points for placement of titanium implants in the dental arch bone. The dentist, based on this image information, deliberated on the best technique that his vision allowed to achieve. After that the surgeon needed to make cuts in the gum in order to obtain the exposure of that bone and then drill it in order to apply the titanium implant in the cavity. Hence the emergence of the firstborn technique that revolutionized dentistry in the recovery of missing teeth.

[005] Later, this technique began to be enhanced by the advent of 3D computerized systems (CT scans), along with resin molds, modeled and applied on gums and teeth for orienting, through holes called surgical guides, direct piercing of the dental arch over the gum, with minimal incision in the gum.

[006] The evolution of the surgical guide adoption system in relation to the previously practiced process stems from the fact that the intervention is more secure, since, by Unlike in the first case, gum cutting is no longer adopted, and those cited drawbacks and contraindications of the implant are no longer experienced.

[007] Dental implant surgery used with guided implant technology (technique referred to here as guided surgery or guided implant) is performed without cuts or trauma to patients, and with considerable time and cost savings.

This technique was widely celebrated in the scientific world over those of conventional surgery. However, even this technique has limitations due to the hardness, costliness and slowness necessary to prepare the patient before undergoing guided surgery, as it uses the conventional dental laboratory system - cast casting, wax modeling, resin , inclusion by dental press and other materials.

[009] The preparation process for the patient who will undergo guided surgery is, until then, extremely laborious and also spends a lot of time before a process that requires interaction between the radiological laboratory, the prophetic laboratory and the dentist / Prosthesis.

The traditional (cut) surgery system and the guided (uncut) surgery system differ greatly. But still, the guided system continues to adopt very labor-intensive and time-consuming prosthetic lab procedures. Given that this is an integral and necessary part of pre-preparation for guided surgery, operosity, burden and time waiting times limit the use of this technique.

What is known by the state of the art is that the guided implant procedure begins with a thorough radiological analysis by means of computed tomography examinations, necessary for the knowledge of the patient's facial and oral anatomy.

During this examination, in addition to the patient, the radiologist must scan a previously prepared acrylic resin mold. This mold should fit perfectly in the dental arch, accommodating teeth and gum, because the patient will be biting during the CT scan. Thus, this mold should be ready when the patient goes to the radiological clinic.

[0013] To produce this mold, called a tomographic mold here, the dentist must perform a dental arch impression of the patient, cast this impression in plaster and with this plaster model in hand, send to a prophetic laboratory where the technician will build a framework of acrylic resin on the model's teeth and gums. This frame should have some unique characteristics: it should fit perfectly over the teeth, should not have any instability after fitting, should be of sufficient thickness and size to support mouth handling. Also, it should be marked at three or more points with a radiopaque material (usually "gutta percha", a typical dental office material).

Making this resin framework follows the same steps within a prophetic laboratory that making a total denture prosthesis may require: 1. On this model of initial plaster, a replica of this model is created, removing the retentions that might not allow the fitting of the frame.

2. With this second retention-free plaster model, the technician should apply a layer of wax and carve it over the teeth and gum to create a structure exactly the same as the final framework required.

3. This wax shaping undergoes a process called inclusion and pressing so that it is "converted" to acrylic resin.

4. Removal of embedding material, cleaning and polishing.

5. Final fit on the first model, so you are sure that the acrylic frame will fit into the mouth.

Each step of these cited above consumes time, dental materials and requires the application of extremely skilled labor, resulting in a higher cost.

Further, each time the work structure is recreated, the inherent distortions of the impression materials, plaster and embedding materials required to complete the work are considerably increased. Each time you change steps, a distortion is added:

[0017] Patient Molding → Plaster Model → Plaster Model Duplication and Retention Removal → Non-Retention Model Duplication and Scaffolding Wax Modeling → Modeling Muffle Inclusion.

Thus, a CT Scan adjustment consultation on the patient prior to surgery is always required, and once again consumes office time, patient time and requires qualified and trained labor for this adjustment. What makes this technique very sensitive is that all steps are delicate and necessary. Failure to do so can result in technique failure.

After this procedure, the patient is referred to the radiological clinic where the imaging exam is performed: one of the patient with the tomographic framework in position in his mouth, and the other only from the tomographic framework. A tomography of the tomographic framework alone is necessary due to the distortions caused by the metallic elements of the dental restorations that are present in most patients. By scanning alone, this scan will copy all the details of the undistorted tomographic framework, including the patient's teeth and gums, and will form the basis for the final surgical guide.

[0020] The laboratory then has in its hands two complete digital tomographic files. These files are then correctly aligned and joined together to form a single examination, which contains both the patient's bone anatomy information and the tomographic framework information (teeth and gum fitting region, without artifacts). For this junction we use the radiopaque points that were made in the tomographic framework and that appear in both exams clearly.

Using a virtual implant planning computer program, the position of the implants is simulated and a surgical guide is created by blending the 3D virtual information of both the tomographic framework and the implant insertion axis, thus forming a 3D virtual object that contains both the holes to guide the drilling of the drills and maintains the anatomy of a socket in the patient's mouth. This virtual 3D object is then prototyped through 3D printers and forms what we call here the "Surgical Guide" which will then be used during surgery.

The time allotted for completion of dental treatment using this technique may vary according to the degree of complexity of the case, but what really delays the process is the time taken to make the tomographic framework, which can extend 2 to 4 weeks and increase costs.

[0023] The process object of this patent differs from the current process adopted by eliminating several phases to obtain the same final result and with greater precision of surgical guide modeling. This is achieved by eliminating successive physical copies and manual laboratories of retention removal and shaping of the tomographic framework that distort the mold by successive copies, making use of the association between imaging and program. computer software specifically designed for this purpose. There is a considerable waste of time from the moment of the patient's dental arch mold production to the final adjustments and surgical guide termination by the conventional procedure.

BRIEF DESCRIPTION OF THE INVENTION

The present invention is a process of totally innovative, not known by the state of the art, which begins by molding the patient's arch using a plastic tray of the type commonly used for dental molding. The impression material is also of the type commonly used in dental offices, for example, silicones and alginate. Patient referral and this impression for a three-dimensional radiographic imaging examination (computed tomography) that will map the patient's entire facial and dental bone structure to an accuracy of up to 1/4 millimeter.

Two CT scans are performed, one of the patient alone and one of the impression of the dental arch in which the implant is intended, which was performed in the previous step. These two, information digitalized by the computed tomography exam are recorded in an electronic file that will be used by a three-dimensional software, whose objective is, through the analysis of the three-dimensional images obtained (facial mapping of the patient and the details obtained by the image extracted from the mold of your dental arch) produce the Surgical Guide to guide and point out the best implant position of a titanium screw, in order to diagnose the best bone anatomy and aesthetics of the prosthesis to be implanted.

The use of three-dimensional software resources allows simulations to be performed, in a virtual environment, to exhaustion, so that, in the end, the best surgical plan for the intended dental implant can be concluded, and the surgical guide can be constructed by high-tech machines which, based on the study done in the The computer through the developed three-dimensional software will direct the implant allowing precise, safe and blunt surgery, reducing surgery time and patient recovery. Given the best surgical plan verified, a Surgical Guide is created that will perfectly adapt to the patient's mouth, where it contains the devices that will guide the fixation of the osseointegrated pins. These points correspond to those identified in the surgical plane verified through the images obtained by computed tomography, maximized by the interpretation obtained through the software. With the Surgical Guide in position, the implants are fixed without the need for any cut, as the screws pass through a small gingival entry hole, which makes the surgery less traumatic and more comfortable for the patient and surgeon.

After the osseointegration interval of the implants, the dental prosthesis is adjusted to the patient's mouth so that he can perform the chewing process and smile perfectly again. Considering that there are no surgical cuts or stitches, similar teeth can be applied more quickly compared to the cases in which cuts and stitches are used on the patient.

This innovative procedure has excluded the need for the production of plaster or resin molds produced by prophet, increasing the accuracy due to the non-incidence of imperfections arising from the sequence of copies by casting or casting, and also because it does not require the tomographic framework. in resin.

Since surgical guides will be designed directly by the three-dimensional software using the information from the impression tomography and then printed directly on conventional prototyping printers (3D printing), decreases the time previously employed and significantly increases the quality of accuracy due to the virtual adjustments provided by the software.

BRIEF DESCRIPTION OF THE FIGURES

The present invention will hereinafter be described based on its figures:

Figure 1 is a block diagram of the step flow diagram of a state of the art process.

Figure 2 is a block diagram of the process step flowchart of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0033] Figure 1, represented by a flowchart, recalls the current state of the art process for obtaining a surgical guide. The sequential phases to reach the goal of producing a surgical guide for dental implants are as follows: a Dental arch molding (1); o Casting plaster from the impression, creating a plaster model (2); Wax Retention Coating (3); Duplication of the plaster model in a second plaster model without retention (4); the waxing (creation of the wax object) of the tomographic framework on the second plaster model (5); the inclusion in dental "muffle" of the waxing to be converted into a piece of acrylic (real tomographic framework) (6); the manual finishing of the tomographic framework (7), the adjustment of the tomographic framework in the patient to check all contacts and their proper fit, a phase that requires clinical consultation (8); The Imaging (tomography) of the patient biting the tomographic framework (9); Imaging (tomography) only of the tomographic framework (without the patient) (10); Importing and aligning the two scans for an Implant Simulation and Implant Planning computer program (11); Making the Surgical Guide by 3D Printing or Rapid Prototyping techniques (12).

The phases 1.8-11 correspond to those in which the need for the presence of the patient is verified. Phases 2-7 determine the unnecessary presence of the patient to the procedures. Phases 11 and 12 correspond to the virtual work, without the presence of the patient.

It should be noted, however, that there is a considerable loss of precision from phase 1 to phase 2, phase 3 to phase 4, phase 5 to phase 7 and phase 10 to phase 11. tomographic framework obtained by successive copies.

The inventive process for patent recognition, totally innovative and not known by the state of the art, is characterized by a "PROCESS FOR OBTAINING CURRENT SURGICAL GUIDELINES USED FOR DENTAL IMPLANTS" and begins by performing molding the patient's arch using a plastic (non-metal) tray of the type commonly used for dental impression. The impression material is also of the type normally used in dental offices, eg silicones, alginate etc.

Referral of the patient and this impression to a three-dimensional radiographic imaging examination (tomography which will map the patient's entire facial and dental bone structure to within 1/4 millimeter accuracy.

Two CT scans are performed, one of the patient alone and the other of the impression of the dental arch in which the implant is intended, which was performed in the previous step.

These two informations digitalized by the computed tomography exam are recorded in an electronic file that will be used by a three-dimensional software, whose objective is, through the analysis of the three-dimensional images obtained (facial mapping of the patient and the details obtained by the extracted image). of your dental arch), produce the Surgical Guide to guide and point out the best position of the titanium screw implant in order to diagnose the best bone and aesthetic anatomy of the prosthesis to be implanted. The use of three-dimensional software resources allows simulations to be performed, in a virtual environment, to exhaustion, so that, in the end, the best surgical plan for the intended dental implant can be concluded, and the surgical guide can be constructed by high quality machines. technology that, based on computer-based study using the developed three-dimensional software, will direct the implant allowing accurate, safe and blunt surgery, reducing surgery time and patient recovery.

Faced with the best surgical plan verified, a Surgical Guide is created that will perfectly adapt to the patient's mouth, where the patient himself contains the devices that will guide the fixation of the integrated bone pins. These points correspond to those identified in the surgical plan. verified by the images obtained by the computed tomography, maximized by the interpretation obtained by the computer program. With the Surgical Guide in position, the implants are fixed without the need for any cutting, as the screws pass through a small gingival entry hole, which makes the surgery less traumatic and more comfortable for the patient and surgeon. After the osseointegration interval of the implants, the dental prosthesis is adjusted to the patient's mouth so that he can perform the chewing process and smile perfectly again. Considering that there are no surgical cuts or stitches, similar teeth can be applied more quickly compared to the cases in which cuts and stitches are used on the patient. In the vast majority of cases the patient resumes normal activities on the same day.

This innovative procedure excluded the need for the production of plaster or resin molds produced by prophetics, as it did not require the resin tomographic framework. Since the surgical guides will be designed directly by the three-dimensional software using information from the impression tomography and then printed on conventional prototyping printers (3D printing).

[0042] The present object of the invention aims to innovatively equate the time and materials spent for the preparation of surgical guides, with the need for the above mentioned phases 2, 3, 4, 5, and 6, respectively, ie , the creation of a tomographic framework through traditional methods.

With the innovation implemented by the new process of obtaining the surgical guide, in relation to the process precedent, some competitive advantages will be evident: speed and quality (precision).

The advantage of speed in the new process of producing the surgical guide is in the elimination of phases 2,3,4,5 and 6 and facilitation of phases 7 and 8, above, in which the prosthetic / prosthesis would undertake, in the process of the current state of the art, an artisanal work of eliminating retentions, distortions of copies, still excess or lack of impression materials (resins, plaster, waxes, etc.), waxing and inclusion in dental muffle to create the tomographic template.

Concerning the quality and precision, even with all the care and technique employed by the prosthesis professional, it will be difficult to eliminate the distortions that, at another stage, will be transferred to the intended tomographic framework, thus requiring them to be made. adjustments by the surgeon by filling or wearing the finished part directly into the patient's mouth. In the case of the new process, since successive copies of the dental arch are not made, the imperfections of this process are eliminated beforehand.

Reading the tomography images from the impression through the three-dimensional software will generate a perfect 3D final image, where the retentions will be digitally eliminated and the tolerance margins applied in the adjustment of the prototyping part, which will perfectly fit the dental arch on which the implant is intended, without the need for the tomographic framework.

[0047] The presentation of this descriptive report will provide the necessary scientific information. the constructive viability of the invention.

In view of these characteristics, in the interest of the final client, a series of procedures are set up, ranging from the performance of imaging examinations, through the manufacture of surgical guides, to the final stage of the implant surgery itself.

With the main objective of minimizing the cost of manufacturing surgical guides or buccal molds, a new technique for manufacturing these same objects has been developed, through a three-dimensional software that interprets the particular information about the patient's dental arch molding, printing the final product directly on a conventional prototyping printer (3D printing), making it unnecessary to participate in the tomographic framework in the finalization of the oral surgical guide used in guided dental implant surgery.

Figure 2, represented by a flow chart, presents the innovations not achieved by the state of the art. The stages to reach a surgical guide of this new technology include: Dental arch molding (12); Imaging (tomography) of the patient naturally (13); Imaging (tomography) only of the impression (without the patient) (14); the Importation and Alignment of the two scans for an Implant Simulation and Implant Planning computer program (15); Virtual casting of the mold by computer program (16); Virtual Removal of Holds (17); Virtual adjustment of tolerance margins (18); Virtual Creation of the teeth / gum fitting framework (19); Guide Making Surgical by 3D printing or rapid prototyping techniques (20).

Phases 12, 13, 14 and 20 correspond to those in which the presence of the patient is required. The phases 15, 16, 17, 18 and 19 correspond to the virtual work, without the presence of the patient.

[0052] It is noteworthy, although there is NO phase shift in any loss of accuracy.

In the computer program environment, the images will be worked in order to identify, through the patient's facial mapping, to orient and point the best implant position, by the integration of the two images produced by the computed tomography. From the completion of this information with the elimination of retentions, implementations of adjustments and employing tolerance margins, the generated electronic file will be ready for its last phase, which is the production of the Surgical Guide piece for dental implant guided surgery. With this file, the three-dimensional software issues print command on prototyping equipment (3D printer) with individual patient characteristics, producing the guide that will be used in the guided implant surgical procedure.

Despite the fact that the manufacture of custom surgical guides is already public knowledge, the innovation brought by the required patenting process excludes phases of its production, especially when the models in plaster, resin, wax and other materials were produced by technicians. prophetic or prosthetic by artisanal means. Through this innovative process the surgical guides are produced completely within three-dimensional software. It is made by means of a rapid prototyping printer (3D printing), which is achieved faster and better by the precision with which the piece fits into the dental arch.

[0055] The functional combination of this information (impression imaging files, three-dimensional software and 3D printer) enables the ultimate goal to be achieved, namely the production of custom surgical guides to be accomplished with a considerable reduction in time. and cost to the end user who wants to undergo dental implant surgery, which in itself would make the claim for the patented technology economically viable.

Claims

1. Process for obtaining custom surgical guides for use in uncut dental implant surgery, comprising:

get mold by molding the patient's dental arch

(12);

obtain tomographic images of the patient's facial and dental bone structure naturally (13); obtain CT images only of the cast, without the patient (14); import the two tomography images into an implant simulation and implant planning computer program and align the images in the computer program (15); virtually casting the mold by means of the computer program (16); virtually remove the retentions (17);

adjust virtually the tolerance margins (18); virtually create the teeth / gum fitting framework (19);

make the Surgical Guide from the virtual docking framework, using 3D printing techniques or rapid prototyping (20).