A moldless fabrication method and system for prostheses

Abstract

This application provides a moldless fabrication method and system for prostheses, comprising: importing scanned data into design software to form a digital oral model, wherein the scanned data includes: chamber scan data and intraoral scan data; designing a digital prosthesis model based on the digital oral model; verifying the digital prosthesis model according to pre-established technical parameters, and modifying the digital prosthesis model according to the verification results to obtain a modified digital prosthesis model that meets the technical parameter requirements, wherein the technical parameters include: adjacent parameters, occlusal parameters, and marginal placement parameters; cutting and sintering the prosthesis according to the data of the modified digital prosthesis model to form the prosthesis; and glazing and polishing the prosthesis. This allows the produced prosthesis to be perfectly matched and positioned in the oral cavity without the need for grinding adjustments, thus eliminating the need for model matching and verification before installation in the oral cavity, and solving the technical problems of complex, time-consuming, and costly manufacturing processes in existing prostheses.

Description

Technical Field

[0001] This application relates to the field of dental implant technology, and more specifically, to a method and system for fabricating prostheses without molds. Background Technology

[0002] In existing dental implant technology, after the restoration (such as a fixed all-zirconia crown) is sintered, the staff needs to manually work the porcelain to adjust the tooth shape to meet the reasonable arch curvature and aesthetically pleasing natural form. After repositioning it back into the model, the inner crown needs to be adjusted, and the contact relationship between the corresponding adjacent teeth needs to be adjusted to just contact and achieve the appropriate tightness. The occlusal contact state of the cusps and fossae of the corresponding teeth needs to meet the centric occlusal relationship. To ensure that the prosthesis is properly positioned, the restoration needs to be ground extensively at the porcelain-working station. This process is cumbersome, time-consuming, and requires a certain level of technical skill from the operators.

[0003] Therefore, the existing process for fabricating restorations is as follows: design - cutting - sintering - checking proximal and occlusal surfaces - placement - adjusting proximal and occlusal surfaces - shaping - glazing and polishing - forming the finished product. This process for producing a full zirconium crown (restoration) is complex, time-consuming, and costly.

[0004] Therefore, existing technologies need to be improved. Summary of the Invention

[0005] The purpose of this application is to provide a moldless fabrication method, system, device, and computer-readable storage medium for restorations, aiming to solve the technical problems of complex, time-consuming, and costly manufacturing processes for restorations in the prior art.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0007] This application provides a method for fabricating a restoration without a mold, wherein the method includes the following steps:

[0008] The scanned data is imported into the design software to form a digital oral model. The scanned data includes: cavity scan data and oral scan data.

[0009] A digital prosthesis model was designed based on a digital oral model;

[0010] The digital restoration model is tested according to the pre-established technical parameters, and the digital restoration model is modified according to the test results to obtain a modified digital restoration model that meets the technical parameter requirements. The technical parameters include: adjacent parameters, occlusal parameters, and marginal placement parameters.

[0011] Based on the data from the modified digital restoration model, the restoration is cut and sintered to form the physical restoration.

[0012] The restoration is then glazed and polished.

[0013] In one implementation, prior to the step of designing a digital prosthesis model based on a digital oral model, the method further includes the following step:

[0014] The occlusal relationship of the digital oral model was examined based on the actual oral plaster model. The gap parameters between adjacent teeth and the opposing teeth were detected in the range of 0.06-0.08 mm through two-dimensional cross-section.

[0015] In one implementation, the step of designing a digital prosthesis model based on a digital oral model specifically includes:

[0016] Different anatomical morphological parameters were set for the anatomical design of the restorations based on different types of fixed restorations. These fixed restoration types included: fixed full crowns (via intraoral scan), fixed all-ceramic crowns, fixed temporary crowns, fixed pure titanium crowns, and fixed all-zirconia crowns. The anatomical morphological parameters included: adhesive gap, additional adhesive gap, distance to the margin line, smoothing distance, bur radius, bur compensation spacing, margin offset, margin angle, extension compensation, and compensation angle. The correspondence between the fixed restoration type and the anatomical morphological parameters was as follows: for fixed full crowns (via intraoral scan), the adhesive gap was 0.02 mm, and the additional adhesive gap was 0.0 mm. The anatomical parameters for fixing an all-ceramic crown are as follows: 3mm, distance to the edge line is 0.8mm, smoothing distance is 0.2mm, bur radius is 0.4mm, bur compensation spacing is 0.4mm, edge offset is 0.08mm, edge angle is 15°, extension compensation is 0.05mm, and compensation angle is 65°. The additional adhesive gap is 0.03mm, the additional adhesive gap is 0.05mm, the distance to the edge line is 0.8mm, the smoothing distance is 0.2mm, the bur radius is 0.4mm, the bur compensation spacing is 0.4mm, the edge offset is 0.08-0.1mm, and the edge angle is 15°. °, extension compensation is 0.05mm, compensation angle is 65°; among the anatomical parameters for fixing the temporary crown, the adhesive gap is 0.04mm, the additional adhesive gap is 0.12mm, the distance to the edge line is 0.8mm, the smoothing distance is 0.2mm, the bur radius is 0.5mm, the bur compensation spacing is 0.5mm, the edge offset is 0.1mm, the edge angle is 15°, extension compensation is 0.1mm, and compensation angle is 65°; among the anatomical parameters for fixing the pure titanium crown, the adhesive gap is 0.02mm, the additional adhesive gap is 0.03mm, and the distance to the edge line is 0.8mm. The smoothing distance is 0.2 mm, the bur radius is 0.5 mm, the bur compensation spacing is 0.5 mm, the edge offset is 0.08 mm, the edge angle is 15°, the extension compensation is 0.05 mm, and the compensation angle is 65°. For the fixed full zirconium crown, the adhesive gap is 0.02 mm, the additional adhesive gap is 0.03 mm, the distance to the edge line is 0.8 mm, the smoothing distance is 0.2 mm, the bur radius is 0.4 mm, the bur compensation spacing is 0.4 mm, the edge offset is 0.1 mm, the edge angle is 15°, the extension compensation is 0.05 mm, and the compensation angle is 65°.

[0017] Based on the tooth shape parameters, a digital restoration model is designed, including the tooth shape parameters such as: arch curvature, he curve, overbite and overjet, size ratio of the contralateral corresponding tooth, and he plane.

[0018] In one implementation, the step of designing a digital prosthesis model based on a digital oral model includes:

[0019] A preset distance is set for the digital restoration model, and the required distance from the digital restoration model to the adjacent teeth is detected by a visual distance map. The color displayed in each contact area of ​​the digital restoration model is a uniform safety color.

[0020] Save the data of the digital restoration model.

[0021] In one implementation, the steps of setting a preset distance for the digital restoration model and detecting the required distance from the digital restoration model to adjacent teeth using a visual distance map are as follows:

[0022] The position of the digital restoration model is adjusted so that the digital restoration model is aligned with the shoulder socket of the opposite tooth, the centric relationship of the intercuspal occlusion satisfies the alignment of the occlusal ridge lines of the dental arch, and the opposing functional cusp is aligned with the position of the occlusal axial ridge and triangular ridge of the digital restoration model.

[0023] In one implementation, the steps of testing the digital restoration model according to pre-established technical parameters and modifying the digital restoration model based on the test results to obtain a modified digital restoration model that meets the technical parameter requirements specifically include:

[0024] The adjacent maxillofacial and lingual views of the digital prosthesis model were examined;

[0025] The matching parameters of occlusion and proximal junction were tested and verified. Specifically, the occlusal and proximal junction matching parameters of the digital restoration models were verified according to different types of fixed full crowns and fixed temporary crowns. For anterior teeth with fixed full crowns, the occlusal matching parameter was 0.4 mm and the proximal junction matching parameter was 0.01 mm; for posterior teeth with fixed full crowns, the occlusal matching parameter was 0.48 mm and the proximal junction matching parameter was 0.01 mm; for anterior teeth with fixed temporary crowns, the occlusal matching parameter was 0.2 mm and the proximal junction matching parameter was -0.01 mm; and for posterior teeth with fixed temporary crowns, the occlusal matching parameter was 0.2 mm and the proximal junction matching parameter was -0.01 mm.

[0026] The digital restoration model was tested based on the contact area drawn on the plaster film before the design was completed.

[0027] In one embodiment, the steps of testing the digital restoration model according to pre-established technical parameters and modifying the digital restoration model based on the test results to obtain a modified digital restoration model that meets the technical parameter requirements further include:

[0028] The two-dimensional cross-section of the digital restoration model is detected by visualization. The adjacent contact status of the digital restoration model is displayed in a safe color, and the adjacent parameter is 0.01 mm.

[0029] In one embodiment, the step of testing the digital restoration model according to pre-established technical parameters and modifying the digital restoration model based on the test results to obtain a modified digital restoration model that meets the technical parameter requirements further includes:

[0030] The digital prosthesis model was tested by referring to the adjacent teeth on the digital oral model.

[0031] In one implementation, the step of testing the digital prosthesis model with reference to adjacent teeth on the digital oral model includes:

[0032] The interocclusal space of the imported digital oral model was checked and found to be within 0.1 mm;

[0033] Undercuts on digital prostheses do not require filling, and undercuts on adjacent teeth on digital dental models are not interconnected.

[0034] Check that the edge of the digital restoration model is above the undercut area and that the edge of the digital restoration model fits closely;

[0035] The adjacent teeth and the digital restoration model were checked to ensure they shared a common path of insertion.

[0036] Check the curvature of the digital restoration model and align it with the curvature of the highest point of the arch shape of the adjacent teeth.

[0037] To achieve the above objectives, this application also provides a moldless fabrication system for restorations, comprising:

[0038] The digital data acquisition module is used to acquire three-dimensional data of the patient's oral cavity;

[0039] The data import module imports the scanned data into the design software to create a digital oral model;

[0040] The design module is used to design digital prosthesis models based on digital oral models;

[0041] The testing module is used to test the digital restoration model according to the pre-established technical parameters, and modify the digital restoration model according to the test results to obtain a modified digital restoration model that meets the technical parameter requirements.

[0042] The processing module is used to cut and sinter the modified digital restoration model to form the physical restoration.

[0043] The beneficial effects of the moldless fabrication method and system for restorations provided in this application are at least as follows:

[0044] This application provides a moldless fabrication method and system for prostheses. The method involves designing a digital prosthesis model based on a digital oral model, ensuring the model matches the patient's oral cavity shape and contour. During the design phase, the digital prosthesis model is tested according to pre-established technical parameters, and modified based on the test results to obtain a modified model that meets the technical parameter requirements. The digital prosthesis model is checked and modified in terms of proximal parameters, occlusal parameters, and marginal placement parameters. This allows the modified digital prosthesis model to be accurately simulated for placement. The physical prosthesis (e.g., a crown or bridge) produced based on the digital prosthesis model has a shape and contour roughly similar to the digital model, allowing the physical prosthesis (crown) to be placed without adjustment on the model, meeting shipping requirements. This application is based on extensive testing and verification of numerous samples, summarizing a new design scheme, design parameters, design concepts, testing standards, and technical points to form a moldless fabrication method. This patent application shortens the fabrication time of fixed all-zirconia restorations (crowns), reduces manufacturing costs, and simplifies the process, thereby lowering the technical threshold and facilitating rapid fabrication of all-zirconia crowns by skilled personnel in the field, meeting the industry's production requirements. Compared to the existing technology requiring eight process steps, the improved process of this application only requires four steps: design (design + testing), sintering, glazing and polishing, and final product formation, directly saving four steps, improving work efficiency, and reducing fabrication time. The sintered crown in this application has a uniform shape with the designed digital restoration model, and the sintered crown does not require further zirconia polishing, thus maintaining crown strength, reducing rework rates, and breaking through traditional technical barriers. It accelerates the delivery cycle, based on a clear market advantage. Through unique and innovative testing methods and a complete set of systematic parameter data, the produced restoration can achieve a predictable effect of complete fit and placement in the oral cavity without the need for model matching and verification. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a flowchart of the main steps of a moldless fabrication method for a prosthesis according to an embodiment of this application;

[0047] Figure 2A flowchart illustrating the specific steps of a moldless fabrication method for a restoration according to an embodiment of this application;

[0048] Figure 3 This is a schematic diagram of a moldless fabrication system for an all-zirconia crown according to an embodiment of this application;

[0049] Figure 4 A defect diagram for checking occlusal errors before designing an embodiment of this application;

[0050] Figure 5 This is a schematic diagram of two-dimensional cross-sectional detection according to an embodiment of this application;

[0051] Figure 6 This is a diagram showing the effect of checking the position of the occlusal ridge and triangular ridge of the digitized restoration model in the design of this application embodiment;

[0052] Figure 7 This is a rendering of the scanned shoulder platform according to an embodiment of this application;

[0053] Figure 8 This is a rendering of the edge line of the scanned shoulder platform according to an embodiment of this application;

[0054] Figure 9 This is a rendering of the outer contour of the digital restoration model according to an embodiment of this application;

[0055] Figure 10 A rendering of the contact area was drawn before designing the embodiments of this application;

[0056] Figure 11 This is a diagram illustrating the effect of using two-dimensional screenshots from software for intuitive visual observation and verification in the embodiments of this application. Detailed Implementation

[0057] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0058] Existing technologies suffer from drawbacks such as complex processes, long processing times, and high costs. Furthermore, the repeated finishing of the restoration itself reduces the material strength of zirconia due to grinding, making the restoration (crown or bridge) prone to internal cracking. Therefore, this application proposes a new moldless fabrication process for restorations. Details are as follows:

[0059] A preferred embodiment of this application provides a method for fabricating a prosthesis without a mold, such as... Figure 1 As shown, this embodiment uses a dental crown as a restoration for process description. This includes the following steps:

[0060] S10. Import the scan data into the design software to form a digital oral cavity model, wherein the scan data includes: cavity scan data and oral scan data.

[0061] S20. Design a digital prosthesis model based on the digital oral model.

[0062] The above process is the digital design process for dental crowns. Specifically, the scanned data is imported into the 3Shape design software. The scanned data contains the morphological data of the patient's oral cavity. Based on the morphology of the patient's oral cavity, different types of fixed restorations are determined, and different crowns are designed accordingly. These different types of fixed restorations include: fixed full crowns (based on intraoral scanning), fixed all-ceramic crowns, fixed temporary crowns, fixed pure titanium crowns, and fixed all-zirconia crowns. Different parameters are set for the anatomical design based on the different types of fixed restorations. For example, in the 3Shape design software, data such as adhesive gap, additional adhesive gap, distance to the margin line, smoothing distance, bur radius, bur compensation spacing, margin offset, margin angle, extension compensation, and compensation angle are set before the crown is digitally designed. When designing the digital restoration model, it is necessary to refer to tooth shape parameters, such as arch curvature, hemisphere curve, overbite / overjet, size ratio of the contralateral corresponding tooth, and hemisphere plane. Appropriate tooth shape parameters are selected to match the shape of the patient's oral cavity, thus completing the anatomical design of the digital restoration model and forming a rough digital restoration model.

[0063] S30. The digital restoration model is tested according to the pre-established technical parameters, and the digital restoration model is modified according to the test results to obtain a modified digital restoration model that meets the technical parameter requirements. The technical parameters include: adjacent parameters, occlusal parameters, and marginal placement parameters.

[0064] After the approximate digital restoration model design is completed, the digital restoration model needs to be inspected to ensure that the crown physical object processed according to the shape of the digital restoration model can be well installed on the substrate in the patient's oral cavity. When there are no clear requirements from clinicians for the proximal contact and occlusion design, the setting parameters of the proximal contact parameters and occlusion parameters for the full crown and provisional crown are different. Among them, on the visualization interface of the software, the proximal contact parameters, occlusion parameters, and marginal seating parameters of the digital restoration model are inspected. If the requirements are not met, the digital restoration model needs to be adjusted. For example, the proximal contact relationship (proximal contact parameters) of the digital restoration model should follow the following inspection criteria: taking the adjustment of proximal contact by 0.01 mm as an example, select the distance map in the 3Shape visualization module option, adjust the distance to 0.17 mm, click the inspection function, and check the distance required to reach the adjacent tooth through the software's inspection of the contact point and smoothing function. If the color shown in the mesial and distal contact areas of the crown is the uniform safety color (the safety color is orange) at this time, it means that the approximate digital restoration model does not need to be adjusted in shape. If red or yellow appears (both are non-safety colors, red represents that the proximal contact area is too tight, and yellow represents that the proximal contact area is too loose), it means that the approximate digital restoration model does not meet the requirements and needs to be adjusted in shape. At this time, use the carving function to adjust the shape of the digital restoration model until it turns orange, and obtain the modified digital restoration model. When the crown contact area of the modified digital restoration model is uniformly orange, it is considered qualified after inspection.至此,牙冠的设计已经全部完成,保存修改后数字化修复体模型,根据上述所设置的技术参数和检验方法所设计出的牙冠不需要在经过后续的邻接和咬合的调整。

[0065] S40. Cut and sinter the physical restoration according to the data of the modified digital restoration model.

[0066] A specific cutting machine should be used for cutting the crown physical object, and the cutting parameters should be executed according to the standard. The cutting machine should be regularly inspected for accuracy and calibrated. When sintering, the sintering program should be set according to the porcelain block sintering curve. The crown physical object is formed by cutting and sintering.

[0067] S50. Glaze and polish the physical restoration.

[0068] In order to make the crown physical object shiny, finally, the crown physical object needs to be glazed and polished. In addition, when glazing, do not let the glaze water flow into the inner crown to avoid causing the inner crown to become smaller and unable to be seated.

[0069] This invention involves designing a digital prosthesis model based on a digital oral model, ensuring the model matches the patient's oral cavity shape and contour. During the design phase, the digital prosthesis model is tested against pre-established technical parameters, and modified based on the test results to obtain a modified model that meets the technical parameter requirements. The digital prosthesis model is checked and modified regarding adjacency parameters, occlusal parameters, and marginal placement parameters. This allows the modified digital prosthesis model to be accurately simulated for placement. The actual crown produced based on the digital prosthesis model has a shape and contour that are roughly similar to the digital prosthesis model, allowing the actual crown (prosthesis) to be placed without adjustment on the model, meeting shipping requirements. This application, based on extensive testing and verification of numerous shipments, summarizes and refines a novel design scheme, design parameters, design concepts, testing standards, and technical points, forming a moldless manufacturing method. This patent application shortens the manufacturing time of fixed all-zirconia restorations (crowns), reduces manufacturing costs, and simplifies the process, thereby lowering the technical threshold and facilitating rapid fabrication of all-zirconia crowns by skilled personnel in the field, meeting the production requirements of the industry. Compared to the existing technology requiring eight process steps, the improved process of this application only requires four steps: design (design + testing), sintering, glazing and polishing, and final product formation. This directly saves four steps, improving work efficiency and reducing production time. In this application, the sintered crown has a uniform shape with the designed digital restoration model. The sintered crown does not require further zirconia grinding, thus maintaining crown strength, reducing rework rates, and breaking through traditional technical barriers. This accelerates the delivery cycle, based on a clear market advantage. Through unique and innovative testing methods and a complete set of parameter data, the produced restoration can achieve a predictable effect of complete fit and placement in the oral cavity without the need for model matching and verification.

[0070] like Figure 2 As shown, the specific steps of this embodiment are as follows:

[0071] Step S100: Import the scan data into the design software to form a digital oral cavity model, wherein the scan data includes: cavity scan data and oral scan data.

[0072] Step S150: Before design, check the digital oral model. Check the occlusal relationship of the digital oral model based on the actual oral plaster model. The gap parameters between adjacent teeth and the opposing teeth were detected by two-dimensional cross-section and were in the range of 0.06-0.08 mm.

[0073] In practice, pre-design checks can prevent malocclusion errors caused by malocclusion abnormalities. Checks for malocclusion errors include: examining the malocclusion scan model (e.g., occlusal sweeping). Figure 4As shown in Figure a), the inspection revealed that the occlusal model was not properly adjusted after demolding, resulting in a gap in the bite (e.g., ...). Figure 4 (See Figure b). The specific inspection process is as follows: In the design software, the occlusal relationship of the digital oral model is checked with reference to the actual plaster model. A two-dimensional cross-sectional viewing tool is required for inspection. The gap parameter between adjacent teeth and the opposing teeth is considered normal if it is within the range of 0.06-0.08mm, and abnormal if it exceeds 0.2mm (e.g., ...). Figure 5 As shown in Figures C and D), if any abnormalities are found, a new scan to re-determine the occlusion is required. When such problems are discovered, the model should be returned to the model set, adjusted, and re-scanned after the occlusion is correct. This allows for the detection of abnormalities before the design phase, preventing the digital prosthesis model from failing to properly match the patient's oral cavity shape.

[0074] To ensure accurate edge scanning, the procedure must be performed according to the requirement of not separating the dental model from the actual tooth—repositioning the edge of a single dental model during scanning: Using a scalpel held at a 45-degree angle to the actual dental model, gently and slowly scrape away any tissue obstructing the abutment tooth edge, exposing and clearly defining the edge. This ensures a clear view of the actual model's shoulder before scanning (e.g., Figure 7 As shown in Figure g), after normal scanning (as shown in Figure g). Figure 7 As shown in Figure h), if the shoulder is blurry, it affects judgment, requiring careful inspection and judgment, which is inefficient and slow, and easily leads to defects such as edges being too long or too short. If the shoulder outline is clearer after fine scanning, the shoulder position can be better determined and edge errors can be reduced (e.g., ...). Figure 7 (As shown in Figure i), this ensures the quality of the subsequent digital restoration model design.

[0075] Step S200: Design the anatomical morphology of the prosthesis by setting different anatomical morphology parameters according to different fixed restoration types. The fixed restoration types include: intraoral scan fixed full crown (intraoral scan all-ceramic), fixed all-ceramic crown (fixed all-ceramic), fixed temporary crown (fixed full crown), fixed pure titanium crown (fixed all-titanium), and fixed all-zirconia crown (fixed all-zirconia). The anatomical morphology parameters include: adhesive gap, additional adhesive gap, distance to the edge line, smoothing distance, bur radius, bur compensation spacing, edge offset, edge angle, extension compensation, and compensation angle.

[0076] In the specific process, after importing the scan data (warehouse scan data, oral scan data) into the 3Shape design software, edge line confirmation is performed in the design: when designing the digital restoration model, the model is tilted at a 45° angle to find the highest point of the shoulder platform, to avoid covering the area below the shoulder platform when drawing the edge (without separating model types). Figure 8 (As shown in the middle figure) During the design, tilt the model at a 45° angle to find the highlight lines and identify the edge lines (scan the shipment type). Figure 8 (As shown in the middle k-figure).

[0077] Different types of fixed restorations (internal scan fixed full crowns, fixed all-ceramic crowns, fixed temporary crowns, fixed pure titanium crowns, fixed all-zirconia crowns, etc.) require anatomical morphology design based on different parameters. In the 3Shape design software, data such as adhesive gap, additional adhesive gap, distance to the margin line, smoothing distance, bur radius, bur compensation spacing, margin offset, margin angle, extension compensation, and compensation angle are set before the crown is designed. The correspondence between fixed restoration types and anatomical morphology parameters is as follows: For internal scan fixed full crowns (internal scan all-ceramic), the anatomical morphology parameters are: adhesive gap 0.02mm, additional adhesive gap 0.03mm, distance to the margin line 0.8mm, smoothing distance 0.2mm, bur radius 0.4mm, bur compensation spacing 0.4mm, margin offset 0.08mm, margin angle 15°, extension compensation 0.05mm, and compensation angle 65°; for fixed all-ceramic crowns (fixed all-ceramic), the anatomical morphology parameters are: In the parameters, the adhesive gap is 0.03mm, the additional adhesive gap is 0.05mm, the distance to the edge line is 0.8mm, the smoothing distance is 0.2mm, the bur radius is 0.4mm, the bur compensation spacing is 0.4mm, the edge offset is 0.08-0.1mm, the edge angle is 15°, the extension compensation is 0.05mm, and the compensation angle is 65°; in the anatomical morphology parameters for fixing the temporary crown (fixed full crown), the adhesive gap is 0.04mm, the additional adhesive gap is 0.12mm, and the distance to the edge line is... The anatomical parameters for fixing a pure titanium crown (fixed all-titanium) are as follows: 0.8mm distance, 0.2mm smoothing distance, 0.5mm bur radius, 0.5mm bur compensation spacing, 0.1mm edge offset, 15° edge angle, 0.1mm extension compensation, and 65° compensation angle. The adhesive gap is 0.02mm, the additional adhesive gap is 0.03mm, the distance to the edge line is 0.8mm, the smoothing distance is 0.2mm, the bur radius is 0.5mm, and the bur compensation spacing is 0.5mm. The edge offset is 0.08mm, the edge angle is 15°, the extension compensation is 0.05mm, and the compensation angle is 65°. For the fixed full zirconium crown (fixed full zirconium), the adhesive gap is 0.02mm, the additional adhesive gap is 0.03mm, the distance to the edge line is 0.8mm, the smoothing distance is 0.2mm, the bur radius is 0.4mm, the bur compensation spacing is 0.4mm, the edge offset is 0.1mm, the edge angle is 15°, the extension compensation is 0.05mm, and the compensation angle is 65°. The specific design parameters used are listed in the table below, meeting the standard execution requirements of the model before design and the standard and verification requirements of the scan data, and satisfying the relevant test verification parameters that do not require adjustment and can be properly positioned. The parameters in the anatomical morphology parameter table are as follows:

[0078]

[0079] Step S250: Based on the tooth shape parameters, design a digital restoration model, where the tooth shape parameters include: arch curvature, he curve, overbite and overjet, size ratio of the contralateral corresponding tooth, and he plane.

[0080] Step S300: Set a preset distance for the digital restoration model and detect the required distance from the digital restoration model to the adjacent teeth through a visual distance map, wherein the color displayed in each contact area of ​​the digital restoration model is a uniform safety color.

[0081] In the specific process, during the design phase, the position of the digital restoration model is adjusted to ensure that the digital restoration model aligns with the shoulder socket of the opposite tooth, the centric relationship of the intercuspal occlusion satisfies the alignment of the occlusal ridge lines of the dental arch, and the opposing functional cusp is aligned with the position of the occlusal axial ridge and triangular ridge of the digital restoration model (e.g., Figure 6 (As shown in Figures e and f). The specific process is as follows: Confirmation of the position of the digital restoration model requires achieving a centric relationship of shoulder-fossa alignment, intercuspal interposition, and alignment of the occlusal ridges of the dental arch. Correct occlusal points are required: the distribution of the three-point contact position of the functional cusps—the opposing functional cusp aligns with the occlusal ridge and triangular ridge position of the working model crown (e.g., the occlusal ridge). Figure 6 (As shown in Figures e and f). The inspection process is then performed using software, with different colors corresponding to the set parameters to assess accuracy. Setting the inspection parameter to 0.17 is considered the most accurate and suitable. This ensures 100% reproducibility of the sintered crown.

[0082] Step S350: Save the data of the digital restoration model.

[0083] Step S400: The digital restoration model is tested according to the pre-established technical parameters, and the digital restoration model is modified according to the test results to obtain a modified digital restoration model that meets the technical parameter requirements.

[0084] This process includes: examining the adjacent occlusal and lingual views of the digital prosthesis model; testing and verifying the matching parameters of occlusion and proximal junctions; and examining the digital prosthesis model with reference to the contact areas drawn on the plaster cast before design. Specifically, the digital prosthesis model is designed, and the design process must adhere to standardized design criteria. This avoids situations where the digital prosthesis model is narrower at the top and wider at the bottom, or where the prosthesis's adjacent junctions do not form an "S"-shaped concave surface (e.g., ...). Figure 9 As shown in Figure F, this can lead to misalignment of adjacent surfaces. The design did not adhere to standardized parameters. The position, shape, and size of the adjacent contact area were not fully understood during the design process, resulting in undersized adjacent surfaces. To address these common problems, design guidelines have been established: Adjacent surfaces should form smooth lines in the occlusal view during the design process (e.g., ...). Figure 9As shown in Figure E), the tongue, viewed from the side, should form a tapered, semi-circular shape. Figure 9 (As shown in Figure K); The occlusal matching parameters and proximal contact matching parameters were tested and verified. Different matching parameters were set according to the different types of fixed full crowns and fixed temporary crowns. These parameters were used to verify the occlusion and proximal contact of the digital restoration model to match the parameters and meet the design requirements. Specifically: for anterior teeth with fixed full crowns, the occlusal matching parameter was 0.4 mm, and the proximal contact matching parameter was 0.01 mm; for posterior teeth with fixed full crowns, the occlusal matching parameter was 0.48 mm, and the proximal contact matching parameter was 0.01 mm; for anterior teeth with fixed temporary crowns, the occlusal matching parameter was 0.2 mm, and the proximal contact matching parameter was -0.01 mm; for posterior teeth with fixed temporary crowns, the occlusal matching parameter was 0.2 mm, and the proximal contact matching parameter was -0.01 mm. The specific matching parameters are shown in the table below. The contact area (e.g., ...) was drawn before design. Figure 10 As shown in the figure, this facilitates the design of digital restoration models.

[0085]

[0086] By visually inspecting the two-dimensional cross-section of the digital restoration model ( Figure 11 (See Figure V). The adjacent contact status of the digital restoration model is displayed in a safe color, where the adjacent contact parameter can be 0.01 mm. Verification tools show the adjacent contact status as orange, a safe color. Figure 11 As shown in Figure P, this achieves the effect of not requiring grinding. Figure 11 (As shown in the N diagram).

[0087] Based on the above testing process, the testing process also includes the following, and the specific self-inspection requirements are as follows: ① Check whether the scanned sample has correct occlusion (gap within 0.1mm) and whether the model has been demolded. ② Check whether the abutment teeth have undercuts that need to be filled, and whether the undercuts of adjacent teeth are connected. ③ Check whether the edge of the abutment tooth is above the undercut area and whether the edge is tightly fitted. ④ Check whether the adjacent teeth share the same path of insertion with the abutment teeth (avoiding the formation of undercuts in adjacent teeth). ⑤ Check lateral occlusal / protrusion movements. ⑥ Check whether the occlusion is shoulder-fossa aligned / cusps interlocked, and whether the functional contact points are consistent. ⑦ Check whether the curvature is aligned with the high point of the arch shape of the adjacent teeth. ⑧ Check whether the adjacent contact surface is the widest contact area (parameter conforming to 0.01mm is displayed in orange).

[0088] A digital prosthesis model is considered acceptable if it meets the following conditions. If these conditions are not met, the digital prosthesis model needs to be modified to meet them. Specifically: the occlusal gap in the scanned digital oral model is within 0.1mm; undercuts in the digital prosthesis model do not need to be filled, and the undercuts of adjacent teeth on the digital oral model are not interconnected; the edge of the digital prosthesis model is above the undercut area, and the edge of the digital prosthesis model fits closely; adjacent teeth and the digital prosthesis model share a common path of insertion; the curvature of the digital prosthesis model is aligned with the curvature of the highest point of the dental arch of the adjacent teeth. Through unique and innovative testing methods and a complete set of systematic parameter data, the final produced prosthesis can achieve a predictable effect of complete fitting and placement in the oral cavity without the need for model matching and verification, and without the need for grinding.

[0089] S500: Based on the data of the modified digital restoration model, the restoration is cut and sintered to form the physical restoration.

[0090] S600: Enamel and polish the actual restoration.

[0091] S700: Reposition the physical restoration back onto the oral model and verify that the repositioning and fit of the adjacent parts, occlusion, and margins meet the standards. If all conditions are met, the restoration is shipped (no adjustment is required; it is directly repositioned onto the model).

[0092] The method for fabricating all-zirconia crowns without molds proposed in this application underwent extensive testing and verification using oral scan data and physical samples. Significant human, material, time, and cost were invested in continuously adjusting the suitability of the parameters, ultimately resulting in a matching set of design parameters and testing methods for all-zirconia.

[0093] This application also proposes a moldless fabrication system for all-zirconia crowns, including: a digital data acquisition module, a data import module, a design module, a testing module, and a processing module. The digital data acquisition module is used to acquire three-dimensional data of the patient's oral cavity; the data import module is used to import the scanned data into design software to form a digital oral cavity model; the design module is used to design a digital prosthesis model based on the digital oral cavity model; the testing module is used to inspect the digital prosthesis model according to pre-established technical parameters and modify the digital prosthesis model based on the inspection results to obtain a modified digital prosthesis model that meets the technical parameter requirements; the processing module is used to cut and sinter the modified digital prosthesis model to form the physical prosthesis.

[0094] In summary, this application provides a moldless fabrication method and system for prostheses. A digital prosthesis model is designed based on a digital oral model, ensuring the model matches the patient's oral cavity shape and contour. During the design phase, the digital prosthesis model is tested according to pre-established technical parameters, and modified based on the test results to obtain a modified model that meets the technical parameter requirements. The digital prosthesis model is checked and modified in terms of proximal parameters, occlusal parameters, and marginal placement parameters. This allows the modified digital prosthesis model to be accurately simulated for placement. The actual crown produced based on the digital prosthesis model has a shape and contour that are roughly similar to the digital prosthesis model, allowing the actual crown (prosthesis) to be placed without adjustment on the model, meeting shipping requirements. This application is based on extensive testing and verification of numerous samples, summarizing a new design scheme, design parameters, design concepts, testing standards, and technical points to form a moldless fabrication method. This patent application shortens the fabrication time of fixed all-zirconia restorations (crowns), reduces manufacturing costs, and simplifies the process, thereby lowering the technical threshold and facilitating rapid fabrication of all-zirconia crowns by skilled personnel in the field, meeting the industry's production requirements. Compared to the existing technology requiring eight process steps, the improved process of this application only requires four steps: design (design + testing), sintering, glazing and polishing, and final product formation, directly saving four steps, improving work efficiency, and reducing fabrication time. The sintered crown in this application has a uniform shape with the designed digital restoration model, and the sintered crown does not require further zirconia polishing, thus maintaining crown strength, reducing rework rates, and breaking through traditional technical barriers. It accelerates the delivery cycle, based on a clear market advantage. Through unique and innovative testing methods and a complete set of systematic parameter data, the produced restoration can achieve a predictable effect of complete fit and placement in the oral cavity without the need for model matching and verification.

[0095] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for fabricating a prosthesis without a mold, characterized in that, The method includes the following steps: The scanned data is imported into the design software to form a digital oral model. The scanned data includes: cavity scan data and oral scan data. The occlusal relationship of the digital oral model was examined based on the actual oral plaster model. The gap parameters between adjacent teeth and the opposing teeth were detected in the range of 0.06-0.08 mm through two-dimensional cross-section. A digital prosthesis model was designed based on a digital oral model; The digital restoration model is tested according to the pre-established technical parameters, and the digital restoration model is modified according to the test results to obtain a modified digital restoration model that meets the technical parameter requirements. The technical parameters include: adjacent parameters, occlusal parameters, and marginal placement parameters. Based on the data from the modified digital restoration model, the restoration is cut and sintered to form the physical restoration. The restoration is glazed and polished. The step of designing a digital prosthesis model based on a digital oral model specifically includes: Different anatomical morphology parameters are set according to different types of fixed restorations to design the anatomical morphology of the restoration. The types of fixed restorations include: intraoral scan fixed full crown, fixed all-ceramic crown, fixed temporary crown, fixed pure titanium crown, and fixed all-zirconia crown. The anatomical morphology parameters include: adhesive gap, additional adhesive gap, distance to the edge line, smoothing distance, bur radius, bur compensation spacing, edge offset, edge angle, extension compensation, and compensation angle. Based on the tooth shape parameters, a digital restoration model was designed, including the tooth shape parameters such as: arch curvature, he curve, overbite and overjet, size ratio of the contralateral corresponding tooth, and he plane; A preset distance is set for the digital restoration model, and the required distance from the digital restoration model to the adjacent teeth is detected by a visual distance map. The color displayed in each contact area of ​​the digital restoration model is a uniform safety color. Save the data of the digital restoration model.

2. The method for fabricating a restoration without a mold as described in claim 1, characterized in that, In the step of designing the anatomical morphology of the prosthesis by setting different anatomical morphological parameters according to different fixed repair types... The correspondence between fixed restoration types and anatomical morphological parameters is as follows: For intraoral scan-fixed full-crown types, the anatomical morphological parameters are: adhesive gap 0.02mm, additional adhesive gap 0.03mm, distance to the edge line 0.8mm, smoothing distance 0.2mm, bur radius 0.4mm, bur compensation spacing 0.4mm, edge offset 0.08mm, edge angle 15°, extension compensation 0.05mm, and compensation angle 65°; For fixed all-ceramic crowns, the anatomical morphological parameters are: adhesive gap 0.02mm, additional adhesive gap 0.03mm, distance to the edge line 0.8mm, smoothing distance 0.2mm, bur radius 0.4mm, bur compensation spacing 0.4mm, edge offset 0.08mm, edge angle 15°, extension compensation 0.05mm, and compensation angle 65°; The anatomical parameters for fixing the temporary crown are as follows: 0.03mm gap, 0.05mm additional adhesive gap, 0.8mm distance to the edge line, 0.2mm smoothing distance, 0.4mm bur radius, 0.4mm bur compensation spacing, 0.08-0.1mm edge offset, 15° edge angle, 0.05mm extension compensation, and 65° compensation angle. The anatomical parameters for fixing a pure titanium crown are as follows: 8mm, smoothing distance 0.2mm, bur radius 0.5mm, bur compensation spacing 0.5mm, edge offset 0.1mm, edge angle 15°, extension compensation 0.1mm, and compensation angle 65°. The adhesive gap is 0.02mm, the additional adhesive gap is 0.03mm, the distance to the edge line is 0.8mm, the smoothing distance is 0.2mm, the bur radius is 0.5mm, the bur compensation spacing is 0.5mm, and the edge offset is 0.8mm. The offset is 0.08 mm, the edge angle is 15°, the extension compensation is 0.05 mm, and the compensation angle is 65°. Among the anatomical parameters of the fixed full zircon crown, the adhesive gap is 0.02 mm, the additional adhesive gap is 0.03 mm, the distance to the edge line is 0.8 mm, the smoothing distance is 0.2 mm, the bur radius is 0.4 mm, the bur compensation spacing is 0.4 mm, the edge offset is 0.1 mm, the edge angle is 15°, the extension compensation is 0.05 mm, and the compensation angle is 65°.

3. The method for fabricating a restoration without a mold as described in claim 1, characterized in that, In the step of setting a preset distance for the digital restoration model and detecting the required distance from the digital restoration model to adjacent teeth using a visual distance map: The position of the digital restoration model is adjusted so that the digital restoration model is aligned with the shoulder socket of the opposite tooth, the centric relationship of the intercuspal occlusion satisfies the alignment of the occlusal ridge lines of the dental arch, and the opposing functional cusp is aligned with the position of the occlusal axial ridge and triangular ridge of the digital restoration model.

4. The method for fabricating a restoration without a mold as described in claim 1, characterized in that, The steps of verifying the digital restoration model according to pre-established technical parameters and modifying the digital restoration model based on the verification results to obtain a modified digital restoration model that meets the technical parameter requirements specifically include: The adjacent maxillofacial and lingual views of the digital prosthesis model were examined; The matching parameters of occlusion and proximal junction were tested and verified. Specifically, the occlusal and proximal junction matching parameters of the digital restoration models were verified according to different types of fixed full crowns and fixed temporary crowns. For anterior teeth with fixed full crowns, the occlusal matching parameter was 0.4 mm and the proximal junction matching parameter was 0.01 mm; for posterior teeth with fixed full crowns, the occlusal matching parameter was 0.48 mm and the proximal junction matching parameter was 0.01 mm; for anterior teeth with fixed temporary crowns, the occlusal matching parameter was 0.2 mm and the proximal junction matching parameter was -0.01 mm; for posterior teeth with fixed temporary crowns, the occlusal matching parameter was 0.2 mm and the proximal junction matching parameter was -0.01 mm. The digital restoration model was tested based on the contact area drawn on the plaster film before the design was completed.

5. The method for fabricating a restoration without a mold as described in claim 4, characterized in that, The steps of verifying the digital restoration model according to pre-established technical parameters and modifying the digital restoration model based on the verification results to obtain a modified digital restoration model that meets the technical parameter requirements further include: The two-dimensional cross-section of the digital restoration model is detected by visualization. The adjacent contact status of the digital restoration model is displayed in a safe color, and the adjacent parameter is 0.01 mm.

6. The method for fabricating a restoration without a mold as described in claim 5, characterized in that, The step of verifying the digital restoration model according to pre-established technical parameters and modifying the digital restoration model based on the verification results to obtain a modified digital restoration model that meets the technical parameter requirements also includes: The digital prosthesis model was tested by referring to the adjacent teeth on the digital oral model.

7. The method for fabricating a restoration without a mold as described in claim 6, characterized in that, The step of testing the digital restoration model by referring to adjacent teeth on the digital oral model includes: The interocclusal space of the imported digital oral model was checked and found to be within 0.1 mm; Undercuts on digital prostheses do not require filling, and undercuts on adjacent teeth on digital dental models are not interconnected. Check that the edge of the digital restoration model is above the undercut area and that the edge of the digital restoration model fits closely; The adjacent teeth and the digital restoration model were checked to ensure they shared a common path of insertion. Check the curvature of the digital restoration model and align it with the curvature of the highest point of the arch shape of the adjacent teeth.

8. A moldless fabrication system for restorations, employing the moldless fabrication method for restorations as described in any one of claims 1-7, characterized in that, include: The digital data acquisition module is used to acquire three-dimensional data of the patient's oral cavity; The data import module imports the scanned data into the design software to create a digital oral model; The design module is used to design digital prosthesis models based on digital oral models; The testing module is used to test the digital restoration model according to the pre-established technical parameters, and modify the digital restoration model according to the test results to obtain a modified digital restoration model that meets the technical parameter requirements. The processing module is used to cut and sinter the modified digital restoration model to form the physical restoration.

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