Dental jaw model and designing and manufacturing method thereof
By designing a dental jaw model with an internal support structure and using 3D printing technology to rapidly mold, the problems of long manufacturing time and waste of raw materials in the existing technology are solved, and efficient and low-cost dental equipment manufacturing is achieved.
Patent Information
- Application Number
- CN202510121275.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2016-06-24
- Publication Date
- 2025-06-27
AI Technical Summary
When existing 3D printing technology manufactures dental jaw models, although the solid model has high strength, it has a long manufacturing time, resulting in low efficiency and waste of raw materials, increasing production costs.
The jaw model design with an internal support structure is adopted, and the target jaw model is designed through three-dimensional graphics processing software, and the 3D printing equipment is rapidly formed. The internal support structure is a honeycomb structure, which reduces the consumption of raw materials for printing.
It shortens the manufacturing time of the tooth jaw model, improves manufacturing efficiency, reduces production costs, and saves raw materials and transportation costs.
Smart Images
Figure CN120217570A_ABST
Abstract
Description
[0001] This application is a divisional application of the patent application with the application date of June 24, 2016, the application number of 201610480354.X, and the invention title of "Design and Manufacturing Method of Dental Instruments".
Technical Field
[0002] The present invention relates to the technical field of dental manufacturing, and more precisely, to a design and manufacturing method of dental instruments.
Background Art
[0003] In recent years, the 3D printing technology has set off an industrial wave and has gradually penetrated into various fields of the manufacturing industry. Naturally, the 3D printing technology has also begun to be applied in the invisible orthodontic technology to assist in the production of personalized polymer plastic dental instruments.
[0004] At present, the dental models rapidly prototyped by the 3D printing technology are increasingly accepted by dental material and equipment manufacturers due to their high precision. However, the 3D printing technology has a high cost, especially the raw materials for printing are expensive, which to a certain extent affects its application and promotion. This technology uses a 3D printing forming machine to print the dental models during the orthodontic process, and then uses a positive pressure laminating machine to manufacture dental instruments on the dental models through the pressure generated by compressed air.
[0005] In the prior art, in order to ensure that the manufactured dental models have considerable strength and do not deform under a certain pressure, therefore, the dental models obtained by the 3D printing rapid prototyping machine are usually solid models. Such solid models are not easily deformed and have a large bearing strength for pressure. However, according to the principle of 3D printing, which is layer-by-layer stacking and forming, the forming time of the solid model by printing is relatively long, which affects the manufacturing efficiency. For the invisible orthodontic technology, the number of such dental models is directly related to the patient's orthodontic cycle. The longer the orthodontic cycle, the more dental models need to be manufactured. Calculated by using one model for half a month, a full-mouth orthodontic patient with an orthodontic cycle of 1 year needs a total of 48 dental models. For resin raw materials, the weight of an ordinary solid dental model is about 15 g per piece. Therefore, in the prior art, the dental models consume a large amount of printing raw materials, resulting in waste of raw materials and high production costs; and their quality is relatively larger than that of hollow models, and higher transportation costs are incurred during batch transportation of the models.
Summary of the Invention
[0006] The present invention overcomes the deficiencies in the prior art and provides a design and manufacturing method of dental instruments, which reduces the consumption of printing raw materials. At the same time, it ensures the bearing strength of the dental models for pressure and saves production costs.
[0007] The present invention is realized through the following technical solutions:
[0008] Method for designing and manufacturing dental instruments, including a step of manufacturing a dental cast, and the step of manufacturing a dental cast includes:
[0009] 1) Design a dental cast
[0010] Use 3D graphics processing software to design a target dental cast, and the interior of the dental cast has an internal support structure;
[0011] 2) Rapidly prototype a dental cast with an internal support structure
[0012] Use a 3D printing device to rapidly prototype the dental cast with an internal support structure.
[0013] Before the step of manufacturing a dental cast, it also includes obtaining 3D dental cast data and reconstructing a 3D dental digital model. After the step of manufacturing a dental cast, it also includes pressure molding the instrument, trimming the corners of the instrument, and polishing the instrument.
[0014] The dental cast has an internal support structure.
[0015] The internal support structure is a honeycomb structure.
[0016] The dental cast is rapidly prototyped using a 3D printing device.
[0017] As a preferred embodiment, the pressure molding instrument uses a positive pressure molding method.
[0018] As a preferred embodiment, trimming the corners of the instrument uses manual work or mechanical automation.
[0019] The dental instrument is a polymer dental appliance.
[0020] The polymer dental appliance is a single-layer structure.
[0021] The polymer dental appliance is a two-layer or multi-layer structure.
[0022] Compared with the prior art, the method for designing and manufacturing dental instruments according to the present invention improves the manufacturing process of dental instruments, replaces the interior of the dental cast with a support structure, saves a large amount of raw materials for printing, and reduces the production cost; secondly, due to the optimization of the process for manufacturing the dental cast, it not only ensures the manufacturing accuracy but also shortens the time required for the entire instrument production process, improving the manufacturing efficiency; the weight of the dental cast with an internal support structure involved in the present invention is greatly reduced, which is beneficial to saving the transportation cost during the production process.
Description of the Drawings
[0023] Figure 1 It is a process flow chart of the present invention.
Detailed Embodiment
[0024] The following further describes the present invention in detail with reference to specific embodiments. Please refer to Figure 1 .
[0025] Embodiment 1:
[0026] A method for designing and manufacturing dental instruments, including a step of manufacturing a dental cast model, and the step of manufacturing the dental cast model includes:
[0027] 1) Design a dental cast model
[0028] Use 3D graphics processing software to design a target dental cast model, and the interior of the dental cast model has an internal support structure;
[0029] 2) Rapidly prototype a dental cast model with an internal support structure
[0030] Use a 3D printing device to rapidly prototype the dental cast model with an internal support structure.
[0031] Before the step of manufacturing the dental cast model, it also successively includes obtaining three-dimensional dental cast model data and reconstructing a three-dimensional dental cast digital model. After the step of manufacturing the dental cast model, it also successively includes pressure molding the instrument, trimming the corners of the instrument, and polishing the instrument.
[0032] The interior of the dental cast model has an internal support structure.
[0033] As a preferred embodiment, the internal support structure is a honeycomb structure.
[0034] The dental cast model is rapidly prototyped using a 3D printing device.
[0035] As a preferred embodiment, the pressure molding instrument uses a positive pressure molding method.
[0036] As a preferred embodiment, trimming the corners of the instrument uses manual work or mechanical automation.
[0037] When technicians in a manufacturing workshop carry out the production and manufacturing of dental instruments for a certain case, they usually complete it according to the following technological steps:
[0038] 1) Obtain three-dimensional dental cast model data
[0039] Through a three-dimensional scanning device, such as a three-dimensional scanner, CT scanner, or intraoral scanner, scan to obtain the three-dimensional data of the target dental cast model. It is also possible to directly obtain the three-dimensional data of the target dental cast model from a partner. Preprocess the obtained dental cast model data and delete redundant invalid data.
[0040] 2) Reconstruct a three-dimensional dental cast digital model
[0041] Based on the three-dimensional dental and jaw model data obtained in step 1), a three-dimensional digital dental and jaw model is reconstructed using three-dimensional graphics processing software.
[0042] 3) Fabricate the dental and jaw model
[0043] This step includes two sub-steps: designing the dental and jaw model and rapid prototyping the dental and jaw model with an internal support structure.
[0044] (1) Design the dental and jaw model
[0045] Use three-dimensional graphics processing software to design the target dental and jaw model. The interior of the dental and jaw model has an internal support structure. The three-dimensional graphics processing software uses reverse engineering software such as Magics or geomagic or solidworks. Through the operation of the "partial cavity" tool in one of the reverse engineering software, set the wall thickness to 1.6 mm. After the operation is completed, a dental and jaw model with a hollow interior can be generated. The thickness of the wall of the dental and jaw model can be set according to the size of the dental and jaw model and usage requirements. Design a regular hexagonal honeycomb grid and perform a Boolean operation on the dental and jaw model and the regular hexagonal honeycomb grid to obtain a honeycomb dental and jaw model. The honeycomb dental and jaw model needs to be partially repaired to eliminate the voids generated in the Boolean operation. Then, through the "cut" operation in the software toolbar, set the cutting method to straight-line horizontal cutting and cut along the lowest part below the gingival line. By implementing the above operations, the redundant gingival base part of the virtual dental and jaw model is removed, reducing waste of raw materials and facilitating batch and rapid production in the factory.
[0046] The dental and jaw model with an internal support structure fabricated by the above method not only reduces the weight of the dental and jaw model, but also ensures the load-bearing strength of the dental and jaw model against pressure, and can also save the amount of raw materials used.
[0047] (2) Rapid prototype the dental and jaw model with an internal support structure
[0048] Use a 3D printing device to rapidly prototype the dental and jaw model with an internal support structure. Import the data of the dental and jaw model with an internal support structure obtained after the above steps into the processing terminal of the 3D printer program in STL file format, perform layer information processing and set printing parameters, and select to execute the printing function. Then, the 3D printer nozzle will manufacture and bond layer by layer with the printing raw material according to a predetermined program, and cure layer by layer relying on ultraviolet light. And in the cavity area of the model with an internal support structure, no printing raw material will be ejected, so as to stack layer by layer into a prototype of the dental and jaw model with an internal support structure. Preferably, the 3D printing rapid prototyping device uses an industrial-grade SLA type 3D printer. The internal support structure includes but is not limited to a honeycomb structure.
[0049] 4) Pressure membrane forming instrument
[0050] Select a suitable dental membrane and laminating machine, and debug parameters such as appropriate temperature, air pressure, preheating time, and laminating time. As a specific technical solution, set the parameters as follows: temperature 55°C, air pressure 1.5 atmospheres, preheating time 30 s, and laminating time 15 s. Put the dental jaw model with the internal support structure described in step 3) and the dental membrane into the laminating machine cabin together, close the cabin cover, start the preheating and laminating programs. After the laminating is completed, open the cabin cover, and a device will be pressed out of the dental membrane according to the contour of the dental jaw model. The membrane except the device will be cut off.
[0051] 5) Cut the corners of the device
[0052] Transport the laminated and formed device to the trimming station, and manually or by an automated machine, cut off the excess membrane material outside the dental jaw model. The equipment used can be dental scissors or an automated robotic arm with a cutting program. When cutting, cut 2 mm below the gum line.
[0053] 6) Grind and polish the device
[0054] The device obtained in the above steps is transported to the grinding and polishing station, and manually or by an automated machine, grind and polish the device with the cut-off corners to eliminate defects such as burrs and sharp edges. The equipment used can be a dental handpiece or a mechanical vibration device.
[0055] The design and manufacturing method of the dental device of the present invention improves the manufacturing process of dental devices. By replacing with a support structure inside the dental jaw model, a large amount of raw materials for printing are saved, and the production cost is reduced. Secondly, due to the optimization of the process for manufacturing the dental jaw model, both the manufacturing accuracy is ensured and the time required for the entire device production process is shortened, improving the manufacturing efficiency. The weight of the dental jaw model with an internal support structure involved in the present invention is greatly reduced, which is beneficial to saving the transportation cost during the production process.
[0056] As a preferred embodiment, the dental device is a polymer dental appliance. The polymer dental appliance can be a single-layer structure, or a two-layer or multi-layer structure. The dental device can also be a molar bite guard. For the dental devices processed by the present invention, including single-layer polymer dental appliances, two-layer or multi-layer polymer dental appliances, and molar bite guards, the consumption of intermediate raw materials can be saved, and the production cost can be reduced.
[0057] Example 2: Dental jaw model test
[0058] In this example, tests are conducted on the weight, yield rate, and dental jaw model parameters of the finished dental jaw model.
[0059] This experiment conducted weight tests on three different types of dental models, namely solid models, hollow models, and the models of the present invention with internal support structures. Ten models of each type were manufactured, and their weights were measured. For specific details, refer to Table 1 below.
[0060] Table 1 Weight Comparison of Different Dental Models (Unit: g)
[0061]
[0062] By comparing the weights of the solid models, hollow models, and the models of the present invention, it can be seen from Table 1 that the models made by the present invention are the lightest. The weight of the models made by the present invention is 22.3% less than that of the hollow models, and the weight of the hollow models is 18.9% lower than that of the solid models. Moreover, the strength of the models made by the present invention meets the production requirements. This shows that the dental models made by the present invention can not only reduce the consumption of raw materials but also ensure the strength of the manufactured dental models, without affecting the subsequent production process, and can greatly reduce the production cost.
[0063] Table 2 Statistical Table of the Yield Rate of the Models Used in the Present Invention:
[0064]
[0065] According to the statistics of the actual printing volume in the three months from September to November 2014 shown in Table 2, the printing yield rate of the dental models used in the present invention remained above 96% each month, and the average yield rate reached 98.2%, meeting the production standards.
[0066] Table 3 Comparative Table of the Parameter Design of the Dental Models Used in the Present Invention:
[0067]
[0068] It can be seen from Table 3 that three variables were designed in the experiment, namely wall thickness, mesh hole, and mesh wall / edge. Multiple parameters were designed for each variable. Among them, there were 4 wall thickness parameters, including 1.9 mm, 1.6 mm, 1.3 mm, and 1.0 mm; 2 mesh hole parameters, including 3.0 mm and 5.0 mm; and 2 mesh wall / edge parameters, including 0.3 mm and 0.6 mm. Through experimental comparison, it was found that the design combination of a wall thickness of 1.6 mm, a mesh hole of 5.0 mm, and a mesh wall / edge of 0.6 mm for the dental model parameters was the best. It could not only ensure that the dental model met the requirements for the pressure-bearing strength of the pressure film after printing, including the hardness and surface shape of the dental model meeting the requirements and being consistent with the computer-designed data model, but also could save the printing raw materials to the greatest extent.
[0069] Example 3: Obtaining a Dental Model with an Internal Support Structure
[0070] (1) Imitating the shape of a bee's honeycomb, a hexagonal grid structure was used as the reinforcement structure of the dental model prototype.
[0071] (2) The data size selected in the internal support structure involved in the present invention refers to the size of the dental model: in the usual measurement data, in the horizontal cross-section direction of the dental model, the incisor part at the narrowest part of the gum is more than 7mm, and the molar part is generally more than 12mm. Therefore, the inscribed circle size of the hexagonal grid structure is selected to be less than 5mm. A relatively sufficient test verification has been carried out on this size, see Table 3 Test Comparison Table, and it was finally decided to adopt the rule of 1.6mm shell, 5mm mesh, and 0.6mm grid wall thickness for design and production based on the existing performance materials.
[0072] (3) The specific steps are as follows:
[0073] ① Design a standard hexagonal grid honeycomb structure in solidworks or other 3D design software, with a cross-sectional size of 80mm×80mm and a height of 50mm, and output it in STL format;
[0074] ② In Magics software, firstly, take in the original data of the 3D dental model prototype to be printed, which is the solid model data, and then take in the honeycomb structure data designed in step ①. At this time, it should be noted that the dental model data should be located in the honeycomb data, that is, the dental model position is within the honeycomb position area, and is set on the swing plate plane;
[0075] ③ The prototype data of the dental model is processed and reduced by 0.8 mm, that is, the core shape is retained, and then the core shape is intersected with the honeycomb shape to obtain the honeycomb reinforcement structure inside the dental model;
[0076] ④ Perform the second step of processing on the prototype data of the dental model, and draw the shell by 1.5mm, that is, set the wall thickness to 1.5mm to obtain the shell shape;
[0077] ⑤ intersecting the honeycomb reinforcement structure obtained in step ③ and step ④ with the shell shape to obtain a prototype structure of the dental jaw model with a honeycomb reinforcement structure;
[0078] ⑥ Use the cut / punch command to cut off the bottom of the prototype, in principle, 2mm below the gum line, and use a straight line to cut it, and the bottom surface is a plane; thus obtaining the final structure, which is the prototype data of the dental model with honeycomb reinforcement structure;
[0079] ⑦Perform platter processing on the printed prototype data in Magics, that is, align the bottom plane through the bottomplane command, set it as the printing plane direction, and place it in a suitable position through the translate command. For example, place it 20 mm away from the edge of the printing area. Generate supports on the bottom surface of the printed prototype through the support command. After setting, output the data format to be printed (that is, data in the format of *.cli or *.sup or *_s.cli), and finally import the data of the above format into a 3D printer using the stereolithography (i.e., SLA) method to obtain an intermediate product of the dental model resin prototype.
[0080] The present invention improves the manufacturing process of dental instruments, changes the characteristic that the printed dental models obtained by 3D printing molding machines are all solid models, saves a large amount of raw materials for printing, and reduces the production cost; secondly, due to the existence of the cavity structure, the printing and manufacturing area is reduced, the printing and molding time is shortened, and the manufacturing efficiency is improved; thirdly, since the present invention adopts an internal support structure, the weight of the dental model is greatly reduced, which is beneficial to saving transportation costs.
[0081] The above description is only an embodiment of the present invention. It is understood that without departing from the concept of the present invention, simple modifications and substitutions of the present invention should be included within the technical concept of the present invention.
Claims
1. A method for designing and manufacturing a dental and maxillofacial model, the steps including: (1) Designing a dental and maxillofacial model using 3D graphics processing software, with an internal support structure inside the dental and maxillofacial model; Designing a regular hexagonal honeycomb grid inside the dental and maxillofacial model; performing a "partial cavity" operation through reverse engineering software tools, setting the wall thickness of the dental and maxillofacial model based on the size and usage requirements of the dental and maxillofacial model, generating an internally hollow dental and maxillofacial model; performing a Boolean operation on the internally hollow dental and maxillofacial model and the regular hexagonal honeycomb grid to obtain a prototype structure of the dental and maxillofacial model with a honeycomb support structure; (2) Based on the prototype structure of the dental and maxillofacial model with the honeycomb support structure, using a 3D printing device to rapidly prototype a dental and maxillofacial model with an internal support structure.
2. The method for designing and manufacturing a dental and maxillofacial model according to claim 1, wherein: The design of the regular hexagonal honeycomb grid inside the dental and maxillofacial model includes: ① Designing a standard hexagonal grid honeycomb structure with software; ② In the design software, importing the original data of the 3D dental and maxillofacial model prototype to be printed, then importing the honeycomb structure data designed in step ①, and placing the dental and maxillofacial model within the honeycomb position area; ③ Shrinking the original data of the dental and maxillofacial model prototype by 0.8 mm, retaining the core shape, and then performing a Boolean operation on the core shape and the honeycomb structure data to obtain a regular hexagonal honeycomb grid inside the dental and maxillofacial model as a honeycomb strengthening structure.
3. The method for designing and manufacturing a dental and maxillofacial model according to claim 2, wherein: It further includes: ④ Performing shelling on the original data of the dental and maxillofacial model prototype to obtain a shelled shape with the wall thickness; ⑤ Performing a Boolean operation on the honeycomb strengthening structure obtained in step ③ and the shelled shape obtained in step ④ to obtain the prototype structure of the dental and maxillofacial model with the honeycomb support structure.
4. The method for designing and manufacturing a dental model according to any one of claims 1-3, characterized in that: It further includes: Repairing the prototype structure of the dental and maxillofacial model with the honeycomb support structure obtained to eliminate the voids generated during the Boolean operation; Performing printing in (2) based on the repaired prototype structure of the dental and maxillofacial model.
5. The method for designing and manufacturing a dental and maxillofacial model according to any one of claims 1 - 3, wherein: The wall thickness of the dental and maxillofacial model designed in (1) is one of the following: 1.0 mm, 1.3 mm, 1.5 mm, 1.6 mm, 1.9 mm, the size of the inscribed circle of the regular hexagonal honeycomb grid ≤ 5 mm, and the wall thickness of the network of the internal support structure is 0.3 mm or 0.6 mm.
6. The method for designing and manufacturing a dental model according to claim 5, wherein: The size of the inscribed circle is equal to 3 mm.
7. The method for designing and manufacturing a dental and maxillofacial model according to claim 5, characterized in that: The size of the inscribed circle is equal to 5 mm, the wall thickness of the network of the internal support structure is 0.6 mm, and the wall thickness of the dental and maxillofacial model is 1.6 mm.
8. The method for designing and manufacturing a dental model according to claim 3, characterized in that: After ⑤, it further includes: ⑥ Cutting off the bottom of the prototype structure with a straight line, and the bottom surface is a plane to obtain the final structure; Performing printing in (2) based on the final structure to obtain the dental and maxillofacial model with the honeycomb support structure.
9. The method for designing and manufacturing a dental and maxillofacial model according to claim 8, characterized in that: After ⑥, it further includes: ⑦ Performing a platter processing on the printing prototype data, that is, aligning the bottom plane, setting it as the printing plane direction, and placing it in a suitable position, generating supports on the bottom surface of the printing prototype, and outputting the data format to be printed; The (2) uses a 3D printing device to rapidly prototype a dental and maxillofacial model with an internal support structure, including: Import the data to be printed output in ⑦ into a 3D printer using the stereolithography method to obtain a dental and maxillofacial model resin prototype.
10. The method for designing and manufacturing a dental and maxillofacial model according to claim 8, characterized in that: In the step of cutting off the bottom of the prototype structure with a straight line: Cut off with a straight line at a position 2 mm below the gingival line of the prototype structure.
11. The method for designing and manufacturing a dental and maxillofacial model according to claim 9, wherein: The appropriate position is 20 mm away from the edge of the printing area.
12. A dental arch model, characterized in that: Obtained by the method for manufacturing a dental and maxillofacial model based on any one of claims 1-11.