Designing and manufacturing method of dental instrument

Abstract

The invention discloses a dental instrument designing and manufacturing method, which comprises a dental model manufacturing step, the dental model manufacturing step comprises: designing a dental model, adopting three-dimensional graphic processing software to design a target dental model, the interior of the dental model being a structure with an internal support; and rapidly forming the dental model with the internal supporting structure, wherein the dental model with the internal supporting structure is rapidly formed by adopting 3D printing equipment. According to the design and manufacturing method of the dental instrument, the manufacturing process of the dental instrument is improved, the interior of the dental model is replaced by a supporting structure, a large number of raw materials for printing are saved, and the production cost is reduced; secondly, as the process for manufacturing the tooth jaw model is optimized, the manufacturing precision is ensured, the time required by the whole instrument production process is shortened, and the manufacturing efficiency is improved; the weight of the tooth jaw model with the internal supporting structure is greatly reduced, and the conveying cost in the production process can be saved.

Description

[0001] This application is a divisional application of a patent application with an application date of June 24, 2016, application number 201610480354.X, and invention name “Design and manufacturing method of dental instruments”. [Technical field]

[0002] The present invention relates to the technical field of dental manufacturing, and more specifically, to a design and manufacturing method of dental instruments. [Background technology]

[0003] In recent years, 3D printing technology has set off a wave of industrialization and has gradually penetrated into various fields of the manufacturing industry. Naturally, 3D printing technology has also begun to be used in invisible correction technology to assist in the production of personalized polymer plastic dental instruments.

[0004] At present, the dental models that are rapidly formed using 3D printing technology have been increasingly accepted by dental material and equipment manufacturers due to their high precision. However, the high cost of 3D printing technology, especially the expensive raw materials for printing, has affected its application and promotion to a certain extent. This technology uses a 3D printing machine to print out the dental model in the correction process, and then uses a positive pressure laminating machine to press and manufacture dental instruments on the dental model through the pressure generated by compressed air.

[0005] In the prior art, in order to ensure that the manufactured dental and maxillary models have considerable strength and do not deform under certain pressure, the dental and maxillary models obtained by 3D printing rapid prototyping machines are often solid models. This solid model is not easy to deform and has a high pressure resistance. However, according to the principle of 3D printing for layer-by-layer stacking and stacking, the solid model takes a long time to be formed by printing, which affects the manufacturing efficiency. For invisible correction technology, the number of such dental and maxillary models is directly related to the patient's correction cycle. The longer the correction cycle, the more dental and maxillary models need to be manufactured. Calculated based on the use of a pair of models for half a month, a full-mouth correction patient with a correction cycle of 1 year requires a total of 48 dental and maxillary models. For resin raw materials, the weight of an ordinary solid dental and maxillary model is about 15g / piece. Therefore, the dental and maxillary models in the prior art consume a lot of raw materials for printing, resulting in a waste of raw materials and high production costs; and their mass is larger than that of hollow models, and the transportation cost is higher when the models are transported in batches. [Summary of the invention]

[0006] The present invention overcomes the shortcomings of the prior art, provides a design and manufacturing method for dental instruments, reduces the consumption of printing raw materials, and at the same time ensures the pressure-bearing strength of the dental model, thereby saving production costs.

[0007] The present invention is achieved through the following technical solutions:

[0008] The design and manufacturing method of the dental instrument comprises a step of manufacturing a dental jaw model, wherein the step of manufacturing a dental jaw model comprises:

[0009] 1) Design the dental model

[0010] A target dental model is designed using three-dimensional graphics processing software, wherein the interior of the dental model has an internal support structure;

[0011] 2) Rapid prototyping of dental models with internal support structures

[0012] The dental model with the internal support structure is quickly formed by using 3D printing equipment.

[0013] Before the step of manufacturing the dental model, it also includes obtaining three-dimensional dental model data and reconstructing a three-dimensional dental digital model. After the step of manufacturing the dental model, it also includes a die-stamping instrument, a corner cutting instrument, and a grinding and polishing instrument.

[0014] The dental jaw model has an internal supporting structure.

[0015] The internal support structure is a honeycomb structure.

[0016] The dental jaw model is quickly formed by using 3D printing equipment.

[0017] As a preferred embodiment, the die-casting apparatus adopts a positive pressure die-casting method.

[0018] As a preferred embodiment, the cutting of the corners of the instrument is performed manually or by automated machinery.

[0019] The dental appliance is a polymer dental cap.

[0020] The polymer dental cap is a single-layer structure.

[0021] The polymer dental cap is a two-layer or multi-layer structure.

[0022] Compared with the prior art, the design and manufacturing method of the dental instrument of the present invention improves the manufacturing process of the dental instrument, replaces the internal support structure of the dental model with a support structure, saves a large amount of printing materials, and reduces production costs; secondly, since the manufacturing process of the dental model is optimized, the manufacturing accuracy is guaranteed and the time required for the entire instrument production process is shortened, thereby improving manufacturing efficiency; the weight of the dental model with an internal support structure involved in the present invention is greatly reduced, which is conducive to saving transportation costs during the production process.

Brief Description of the Drawings

[0023] Figure 1 It is a process flow chart of the present invention. [Specific implementation method]

[0024] The present invention is further described in detail below with reference to specific embodiments. Figure 1 .

[0025] Embodiment 1:

[0026] The design and manufacturing method of the dental instrument comprises a step of manufacturing a dental jaw model, wherein the step of manufacturing a dental jaw model comprises:

[0027] 1) Design the dental model

[0028] A target dental model is designed using three-dimensional graphics processing software, wherein the interior of the dental model has an internal support structure;

[0029] 2) Rapid prototyping of dental models with internal support structures

[0030] The dental model with the internal support structure is quickly formed by using 3D printing equipment.

[0031] Before the step of manufacturing the dental model, it also includes obtaining three-dimensional dental model data and reconstructing a three-dimensional dental digital model. After the step of manufacturing the dental model, it also includes a die-stamping instrument, a corner cutting instrument, and a grinding and polishing instrument.

[0032] The interior of the dental model is provided with an internal supporting structure.

[0033] As a preferred embodiment, the internal support structure is a honeycomb structure.

[0034] The dental jaw model is quickly formed by using 3D printing equipment.

[0035] As a preferred embodiment, the die-casting apparatus adopts a positive pressure die-casting method.

[0036] As a preferred embodiment, the cutting of the corners of the instrument is performed manually or by automated machinery.

[0037] When manufacturing dental instruments for a particular case, the technicians in the manufacturing workshop usually follow the following process steps:

[0038] 1) Obtain 3D dental model data

[0039] The 3D data of the target dental model can be obtained by scanning with a 3D scanning device, such as a 3D scanner, CT scanner or intraoral scanner. The 3D data of the target dental model can also be obtained directly from the partner. The obtained dental model data is preprocessed to delete unnecessary invalid data.

[0040] 2) Reconstruction of three-dimensional dental digital model

[0041] According to the three-dimensional dental model data obtained in step 1), a three-dimensional dental digital model is reconstructed using three-dimensional graphics processing software.

[0042] 3) Make a dental model

[0043] This step includes two steps: designing the dental model and rapidly prototyping the dental model with internal support structure.

[0044] (1) Design of dental model

[0045] The target dental model is designed by using three-dimensional graphics processing software, and the interior of the dental model has an internal support structure; the three-dimensional graphics processing software uses reverse engineering software such as Magics, Geomagic, or Solidworks. Through the "partial cavity" operation of one of the tools in the reverse engineering software, the wall thickness is set to 1.6 mm. After the operation is completed, a dental model with a hollow interior can be generated. The thickness of the dental model wall can be set according to the size of the dental model and the need for use. A regular hexagonal honeycomb grid is designed, and the dental model and the regular hexagonal honeycomb grid are subjected to Boolean operation to obtain a honeycomb dental model. The honeycomb dental model needs to be partially repaired to eliminate the vacancies generated in the Boolean operation. Then, through the "cut" operation in the toolbar of the software, the cutting method is set to a straight horizontal cutting, and the cutting is performed below the lowest point of the gum line. By implementing the above operations, the redundant gum base of the virtual dental model is removed, which reduces the waste of raw materials and facilitates rapid batch production in the factory.

[0046] The dental jaw model with an internal support structure manufactured by the above method can reduce the weight of the dental jaw model, ensure the bearing strength of the dental jaw model against pressure, and save the amount of raw materials.

[0047] (2) Rapid prototyping of dental models with internal support structures

[0048] The dental model with internal support structure is quickly formed by 3D printing equipment. The data of the dental model with internal support structure obtained after the above steps are completed are imported into the 3D printer program processing terminal in STL file format, and the layer information is processed and the printing parameters are set, and the printing function is selected to execute. Then, the 3D printer nozzle will manufacture and bond layer by layer with the raw materials for printing according to a predetermined program, and solidify layer by layer by ultraviolet light. In addition, in the cavity area of ​​the model with internal support structure, the raw materials without printing will be sprayed out, so as to be stacked layer by layer into a prototype of the dental model with internal support structure. Preferably, the 3D printing rapid prototyping equipment adopts an industrial-grade SLA type 3D printer. The internal support structure includes but is not limited to a honeycomb structure.

[0049] 4) Film forming equipment

[0050] Select appropriate dental film and laminating machine, and adjust appropriate parameters such as temperature, air pressure, preheating time, laminating time, etc. As a specific technical solution, set the parameters to: temperature 55°C, air pressure 1.5 atmospheres, preheating time 30s, laminating time 15s. Put the dental model with internal support structure described in step 3) into the laminating machine cabin together with the dental film, cover the cabin, start the preheating and laminating procedures, and after the laminating is completed, open the cabin cover, and the dental film will be pressed into an instrument according to the contour of the dental model, and the film except the instrument will be cut off.

[0051] 5) Cutting off the corners of the instrument

[0052] The mold forming device is transported to the trimming station, and the excess film material outside the dental model is removed manually or by an automated machine. The equipment used can be dental scissors or an automated mechanical arm with a cutting program. When cutting, the cutting is performed 2 mm below the gum line.

[0053] 6) Grinding and polishing equipment

[0054] The instruments obtained in the above steps are transported to the grinding and polishing station, where the instruments with cut corners are ground and polished manually or by an automated machine 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 instrument of the present invention improves the manufacturing process of the dental instrument, replaces the internal support structure of the dental model with a support structure, saves a large amount of printing materials, and reduces production costs; secondly, since the manufacturing process of the dental model is optimized, the manufacturing accuracy is guaranteed and the time required for the entire instrument production process is shortened, thereby improving manufacturing efficiency; the weight of the dental model with an internal support structure involved in the present invention is greatly reduced, which is conducive to saving transportation costs during the production process.

[0056] As a preferred embodiment, the dental instrument is a polymer brace, which can be a single-layer structure or a two-layer or multi-layer structure. The dental instrument can also be a molar jaw pad. The dental instruments processed by the present invention, including single-layer polymer braces, two-layer or multi-layer polymer braces, and molar jaw pads, can save the consumption of intermediate raw materials and reduce production costs.

[0057] Example 2: Dental model test

[0058] In this embodiment, the weight, yield rate and parameters of the finished dental and jaw models are tested.

[0059] In this experiment, three different types of dental models were tested for weight, namely a solid model, a hollow model and a model with an internal support structure of the present invention. Ten of each type were manufactured and their weights were tested. For details, please refer to Table 1 below.

[0060] Table 1 Comparison of weights of different dental models (unit: g)

[0061]

[0062] By comparing the weights of the solid model, the hollow model and the model of the present invention, it can be seen from Table 1 that the weight of the model made by the present invention is the lightest, which is reduced by 22.3% compared with the hollow model, while the weight of the hollow model is reduced by 18.9% compared with the solid model, and the strength of the model made by the present invention meets the production requirements. This shows that the dental and jaw models made by the present invention can not only reduce the consumption of raw materials, but also ensure the strength of the manufactured dental and jaw models, without affecting the subsequent production links, and can greatly reduce the production cost.

[0063] Table 2 Statistics of production yield rate of the model used in the present invention:

[0064]

[0065] According to the actual printing volume during the three months from September to November 2014 as shown in Table 2, the printing yield rate of the dental model used in the present invention remained above 96% every month, and the average yield rate reached 98.2%, meeting the production standard.

[0066] Table 3 comparison table of tooth jaw model parameter design used in the present invention:

[0067]

[0068] As shown in Table 3, the experiment designed three variables, namely wall thickness, mesh and mesh wall / edge. Multiple parameters were designed for each variable, including 4 wall thicknesses, including 1.9mm, 1.6mm, 1.3mm and 1.0mm; 2 meshes, including 3.0mm and 5.0mm; 2 mesh walls / edges, including 0.3mm and 0.6mm. Through experimental comparison, it was found that the design combination of 1.6mm wall thickness, 5.0mm mesh and 0.6mm mesh wall / edge was the best for the dental model parameters, which can ensure that the dental model after printing meets the requirements of the pressure bearing strength of the lamination, including the hardness and surface shape of the dental model meet the requirements, which is consistent with the computer-designed data model, and can save the raw materials for printing to the maximum 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] ⑦ Arrange 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, 20 mm away from the edge of the printing area. Generate support 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 *.cli or *.sup or *_s.cli format). Finally, import the data in the format into a 3D printer using stereolithography (i.e. SLA) 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 the 3D printing machine are all solid models, saves a large amount of printing raw materials, and reduces production costs; secondly, due to the existence of the cavity structure, the printing manufacturing area is reduced, the printing 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 conducive to saving transportation costs.

[0081] The above description is only an embodiment of the present invention. It should be understood that simple modifications and replacements of the present invention should be included in the technical concept of the present invention without departing from the concept of the present invention.

Claims

1. A method for designing and manufacturing a dental instrument, comprising a step of manufacturing a dental model, characterized in that: The step of manufacturing the dental model comprises: (1) Design of dental model The target dental model is designed by using three-dimensional graphics processing software. The wall thickness of the dental model is 1.6 mm. The dental model has an internal support structure. The internal support structure is a hexagonal grid structure. The size of the inscribed circle is less than or equal to 5 mm. The mesh wall thickness of the internal support structure is 0.6 mm. (2) Rapid prototyping of dental models with internal support structures The dental model with the internal support structure is quickly formed by using 3D printing equipment.

2. The method for designing and manufacturing a dental instrument according to claim 1, wherein: Before the step of manufacturing the dental model, it also includes obtaining three-dimensional dental model data and reconstructing a three-dimensional dental digital model. After the step of manufacturing the dental model, it also includes a die-stamping instrument, a corner cutting instrument, and a grinding and polishing instrument.

3. The method for designing and manufacturing a dental instrument according to claim 1, wherein: The size of the inscribed circle is equal to 5 mm.

4. The method for designing and manufacturing a dental instrument according to claim 1, wherein: The dental jaw model is quickly formed by using 3D printing equipment.

5. The method for designing and manufacturing a dental instrument according to claim 2, wherein: The film pressing and forming apparatus adopts a positive pressure film pressing method.

6. The method for designing and manufacturing a dental instrument according to claim 2, wherein: The cutting instrument corners include: when cutting, cutting 2mm below the gum line.

7. The method for designing and manufacturing a dental instrument according to any one of claims 1 to 6, characterized in that: The dental appliance is a polymer dental cap.

8. The method for designing and manufacturing a dental instrument according to claim 7, wherein: The polymer dental cap is a single-layer structure.

9. The method for designing and manufacturing a dental instrument according to claim 7, wherein: The polymer dental cap is a two-layer or multi-layer structure.

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