Injection mold and manufacturing method of a digitalized complete denture

Abstract

The application provides a digital complete denture injection mold and a manufacturing method, and comprises the following steps: a diagnostic denture physical model with a first positioning column is designed and printed according to a digital model; the diagnostic denture physical model is placed into a lower mold box and injection molded to form a negative mold with a dentition groove in the lower mold box; finished teeth are embedded and installed into the dentition groove of the negative mold; a upper mold box is tightly buckled on the lower mold box, and personalized resin plates tightly combined with the finished teeth are formed by injection molding in the upper mold box; the personalized resin plates are fixed on a clamp of a cutting device; the cutting device is started to cut the personalized resin plates to form denture polishing surfaces, and finally a complete denture worn in the mouth is formed. The application advances the combination of the denture and the base before digital cutting, and the base material is firmly combined with the finished teeth during the injection molding process of the personalized resin plates, so that the occlusion error and the bonding strength problem caused by the separate processing and then bonding are avoided.

Description

Technical Field

[0001] This invention relates to the fabrication of complete dentures, specifically to an injection mold for digital complete dentures and its fabrication method. Background Technology

[0002] Complete dentures are the primary restorative method for edentulous jaws, but the current clinical and fabrication processes for complete dentures are extremely cumbersome. While the design process for digital complete dentures has made significant progress, the related fabrication methods remain stagnant, limiting the realization of a fully digital complete denture process.

[0003] Complete dentures consist of a denture base and dentition. Since the denture base and dentition are made of different materials, they are currently fixed together using adhesive bonding. This method, due to the presence of adhesive, makes it difficult to control the relative position of the dentition and denture base, leading to occlusal errors and potential detachment later on. Furthermore, the denture bases in this method are typically paired with custom-printed or machined dentures. Studies have shown that CNC-machined complete dentures have higher precision on the polished surface but lower precision on the occlusal surface, with an average deviation of 0.50mm. They also suffer from long-term problems such as wear resistance, lack of definition, and susceptibility to staining. Summary of the Invention

[0004] This invention provides an injection mold and manufacturing method for a digital complete denture. The complete denture consists of a base and a dentition that is tightly fitted to the base. The manufacturing method includes the following steps:

[0005] S1. Based on the initial clinical impression and jaw position relationship, digitally design a three-dimensional model of the complete denture and print out a diagnostic denture solid model, wherein the diagnostic denture solid model is provided with a first positioning post;

[0006] S2. The dental prosthesis solid model is inserted into the lower mold box with the dentition side facing down. The lower mold box has a top opening and a first positioning groove on the upper end face that cooperates with the first positioning post. The first positioning post provides support and positioning for the diagnostic prosthesis solid model in the lower mold box.

[0007] S3. Inject the first molding material into the cavity in the lower mold box and cure it. Remove the diagnostic denture solid model and form a negative mold with tooth grooves in the lower mold box.

[0008] S4. Insert each finished tooth into the tooth row groove of the negative mold in sequence;

[0009] S5. The upper molded box with a cavity is sealed and fastened to the lower molded box. The upper molded box is provided with a second positioning groove. After the second molding material is injected into the cavity of the upper molded box and cured, a personalized resin disc is formed that is tightly combined with the finished tooth. During the injection molding process, the second molding material is poured into the second positioning groove to form a second positioning post.

[0010] S6. Open the upper mold box and take out the personalized resin disc with the second positioning post that fits tightly with the finished dental arch;

[0011] S7. Fix the personalized resin disc on the rotatable fixture of the cutting equipment. The fixture is provided with a third positioning groove that cooperates with the second positioning post. The second positioning post provides support and positioning for the personalized resin disc on the fixture.

[0012] S8. Start the cutting equipment to cut the personalized resin plate to form a polished surface for the denture. Then remove the personalized resin plate and trim the edges to finally form the complete denture worn in the mouth.

[0013] Furthermore, in step S1, a three-dimensional model of the complete denture with the first positioning post is digitally designed, and a solid model of the diagnostic denture with the first positioning post is printed in one piece; or

[0014] After printing out the diagnostic denture solid model, the prefabricated first positioning post is fixedly installed on the diagnostic denture solid model.

[0015] Furthermore, the diagnostic denture solid model is provided with at least three first positioning posts on the same plane, and the upper end surface of the lower mold box is provided with three first positioning grooves in different directions for accommodating each of the first positioning posts.

[0016] Furthermore, the upper mold box and the lower mold box have similar diameters, and the upper mold box has multiple second positioning grooves on its engaging end face that engages with the first positioning groove.

[0017] In step S5, during the injection molding process, the second molding material is simultaneously poured into the first positioning groove and the second positioning groove to form the second positioning post.

[0018] Furthermore, the upper mold box and the lower mold box are detachably and sealed together by means of clamps or buckles.

[0019] Furthermore, the upper mold box has an injection port and at least one vent on each side, which are connected to the internal cavity of the upper mold box.

[0020] Furthermore, in step S3, agar is used as the first molding material to injection mold a female mold with tooth grooves.

[0021] In step S5, acrylic resin is used as the second molding material to injection mold the personalized resin disc.

[0022] Furthermore, the cavity of the upper mold box is provided with a thickness-oriented scale groove to form a thickness scale on the side of the personalized resin disc.

[0023] An injection mold for the above-mentioned method of manufacturing digital complete dentures, the injection mold is composed of an upper mold box and a lower mold box that are sealed and connected together, the upper mold box and the lower mold box are provided with injection cavities with opposite openings, and the upper mold box and the lower mold box are respectively provided with a first positioning groove and a second positioning groove;

[0024] A female mold with tooth grooves is formed by injection molding in the cavity of the lower mold box, and a personalized resin disc that is tightly bonded to the finished tooth is formed by injection molding in the cavity of the upper mold box.

[0025] The advantages of this invention are:

[0026] 1) The digital complete denture manufacturing method provided by this invention advances the bonding of the pre-made artificial teeth to the denture base before digital cutting. During the personalized resin disc injection molding process, the denture base material and the pre-made teeth are firmly bonded, avoiding the occlusal errors and bonding strength problems caused by the existing separate processing and bonding methods. Simultaneously, the tissue surface precision of the denture base fabricated by this processing method is superior to that of printing and traditional heat treatment methods. The finished teeth also surpass existing cut and printed artificial teeth in terms of layering, strength, wear resistance, and staining resistance. This specific type of box and processing technology solves the processing challenges of fully digital complete dentures. The fully digital complete denture process greatly reduces the operational difficulty in clinics and laboratories, improves patient comfort, reduces the use of manual materials in clinics and laboratories, and lays the foundation for exploring more digital processes and moving towards intelligent manufacturing.

[0027] 2) By injection molding a negative mold with tooth grooves in the lower mold box, the negative mold can provide precise positioning for each finished tooth. After the finished tooth is installed, a personalized resin plate that is tightly bonded to the finished tooth is injection molded again. Compared with the existing technology that uses adhesive to fix the finished tooth, the present invention does not require adhesive and the finished tooth has higher precision.

[0028] 3) The first positioning post provides precise positioning for the diagnostic denture solid model within the lower mold box, while also serving a supporting function. During injection molding of the lower mold box, sealing is not required, thus preventing the diagnostic denture solid model from falling into the lower mold box. The second positioning post provides precise positioning for the personalized resin tray on the fixture. Furthermore, the presence of the first and second positioning posts facilitates the subsequent removal of the diagnostic denture solid model and personalized resin tray from the lower and upper mold boxes. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, 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 the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of a diagnostic denture solid model printed in one piece using 3D printing technology;

[0031] Figure 2 A schematic diagram of a diagnostic denture solid model with a first positioning post;

[0032] Figure 3 This is a three-dimensional view of the lower mold box;

[0033] Figure 4 A schematic diagram showing the mounting of a diagnostic denture solid model onto the lower mold box and its support and positioning via the first positioning post;

[0034] Figure 5 This is a schematic diagram of injection molding inside the lower mold box;

[0035] Figure 6 To create a negative mold with dentition grooves inside the lower mold box after removing the diagnostic denture solid model;

[0036] Figure 7 This is a schematic diagram showing how each finished tooth is embedded into the groove of the dental arch;

[0037] Figure 8 This is a three-dimensional view of the upper mold box;

[0038] Figure 9 This is a schematic diagram showing how the upper mold box is fastened to the top of the lower mold box.

[0039] Figure 10 This is a schematic diagram of injection molding inside the upper mold box;

[0040] Figure 11 A schematic diagram illustrating the formation of a personalized resin disc within the upper mold box that tightly integrates with the finished tooth;

[0041] Figure 12 A schematic diagram of a personalized resin disc with a second positioning post and thickness markings on the side.

[0042] Figure 13 This is a schematic diagram of a rotatable fixture for a cutting device;

[0043] Figure 14 A diagram illustrating the process of securing a personalized resin disc to a clamp;

[0044] Figure 15 This is a schematic diagram illustrating the cutting process of a personalized resin disc.

[0045] Figure 16 This is a schematic diagram of the final complete denture of the present invention. Detailed Implementation

[0046] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0047] To fully understand this invention, detailed steps and structures will be presented in the following description to illustrate the technical solution of this invention. Preferred embodiments of the invention are described in detail below; however, in addition to these detailed descriptions, the invention may have other embodiments.

[0048] Reference Figure 1 As shown, this invention provides a method for fabricating a digital complete denture. The complete denture consists of a denture base and a set of teeth that are tightly fitted to the denture base. The fabrication method includes the following steps:

[0049] Step S1: Based on the initial clinical impression and jaw position relationship, digitally design a three-dimensional model of the complete denture and print out the diagnostic denture solid model 10. In clinical application, the digitally designed complete denture can be printed first, and then a flexible material can be applied to the gingival groove of the denture base for the patient to try on, and a functional pressure impression of the complete denture can be taken. Based on the functional pressure impression of the complete denture, the final three-dimensional model of the denture can be digitally designed again.

[0050] like Figure 2 As shown, the diagnostic denture solid model 10 has three first positioning posts 11 fixed at different locations, preferably with the first positioning posts 11 located on the labial / buccal side of the denture base. In one embodiment of the invention, the digital model of the first positioning posts 11 can be pre-fitted with the three-dimensional model of the complete denture in software, and then the entire diagnostic denture solid model 10 with the first positioning posts 11 can be printed out. In another embodiment, marker points can be added at different locations in the three-dimensional model of the complete denture, and the diagnostic denture solid model 10 can be printed out first, and then the prefabricated first positioning posts 11 can be fixedly connected to the marked points.

[0051] Step S2: Place the dental model 10, dentition side down, into the lower housing 20 with a cavity, as shown. Figure 3As shown, the lower mold box 20 has a top opening and a first positioning groove 21 on its upper end surface that mates with the first positioning post 11. The first positioning post 11 provides support and positioning for the diagnostic denture solid model 10 within the lower mold box 20, and ensures that the dentition of the diagnostic denture solid model 10 is located below the upper end surface of the lower mold box 20.

[0052] Step S3: Inject agar into the cavity inside the lower mold box 20 and allow it to solidify, as shown below. Figure 5 As shown, during injection molding, ensure the agar covers the upper surface of the lower mold box 20. Then, remove the diagnostic denture solid model 10 and form an agar negative mold 30 with dentition grooves 31 inside the lower mold box 20, as shown. Figure 6 As shown.

[0053] Step S4: Sequentially insert each finished tooth 40 into the tooth row groove 31 of the female mold 30, such as... Figure 7 As shown, each finished tooth 40 has the same shape and size as the dental arch portion of the three-dimensional model of the complete denture, so as to ensure the embedding posture of each finished tooth 40.

[0054] Step S5: Seal and fasten the upper mold box 50 with the cavity onto the lower mold box 20, as shown. Figure 8 As shown, the upper molded box 50 and the lower molded box 20 have similar diameters. The upper molded box 50 is provided with three second positioning grooves 51 corresponding to the positions of the first positioning groove 21. After the upper molded box 50 is fastened to the top of the lower molded box 20, each first positioning groove 21 and each second positioning groove 51 cooperate to form a radial through hole. Figures 8-9 As shown. To ensure the stability and sealing of the connection between the upper mold box 50 and the lower mold box 20, a clamp can be used to clamp the upper mold box 50 and the lower mold box 20 together, or the side walls of the upper mold box 50 and the lower mold box 20 can be provided with flip-locking components to achieve the stability of the connection between the two.

[0055] The upper molded box 50 has an injection port 52 at one end and two vents 53 at the other end. The entire injection process maintains stable pressure to ensure no air bubbles are present, reducing defects and cracks. The injection port 52 is connected to an injection pressure pump, which injects acrylic resin into the cavity of the upper molded box 50. After curing, a personalized resin disc 60 is formed inside the upper molded box 50, tightly bonded to the finished tooth 40. The personalized resin disc 60 is disc-shaped with a diameter of 98mm, matching the CNC cutting machine fixture. Furthermore, during the injection process, a second molding material is injected into each radial through-hole to form multiple second positioning posts 61, such as... Figure 10 As shown.

[0056] In addition, the upper mold box 50 has a thickness-oriented graduated groove inside its cavity to form a thickness scale 62 on the side of the injection-molded personalized resin disc 60. This thickness scale 62 can provide a thickness reference for subsequent cutting.

[0057] Step S6: Open the upper mold box 50 and take out the personalized resin disc 60, which has a second positioning post 61 and fits tightly with the finished dental arch. Figure 11 As shown.

[0058] Step S7: Fix the personalized resin disc 60 on the rotatable clamp 70 of the cutting equipment 80. The clamp 70 is provided with a third positioning groove 71 that cooperates with the second positioning post 61. The second positioning post 61 provides support and positioning for the personalized resin disc 60 on the clamp 70.

[0059] Step S8: The cutting device 80 is activated to cut the personalized resin disc 60 to form the polished surface of the denture. The personalized resin disc 60 matches the data of the dentition section with the 3D model of the digitally designed complete denture to determine the cutting range, shape, and cutting path of the base portion within the disc, ultimately completing the digital cutting process of the entire set of teeth. During the cutting process, the clamp 70 can rotate the personalized resin disc 60, working in conjunction with a multi-axis cutting drill to achieve the shaping of complex contours. During the cutting process, the dentist can monitor the cutting progress in real time using the thickness scale 62 on the side of the personalized resin disc 60, improving cutting efficiency and accuracy.

[0060] Finally, remove the personalized resin plate 60 for trimming, removing excess parts including the second positioning post 61, to achieve the final shape. Figure 16 The image shows a complete denture worn intraorally.

[0061] The preferred embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and the devices and structures not described in detail should be understood as being implemented in a conventional manner in the art. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the present invention. This does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the present invention's technical solutions still fall within the protection scope of the present invention.

Claims

1. A method for fabricating a digital complete denture, wherein the complete denture comprises a base and a dentition that is tightly fitted with the base, characterized in that, The manufacturing method includes the following steps: S1. Based on the final clinical impression and jaw position relationship, a three-dimensional model of the complete denture is digitally designed and a diagnostic denture solid model (10) is printed out. The diagnostic denture solid model (10) is provided with a first positioning post (11). S2. The dental prosthesis solid model (10) is inserted into the lower mold box (20) with the dentition side facing down. The lower mold box (20) has a top opening and a first positioning groove (21) on the upper end surface that cooperates with the first positioning post (11). The first positioning post (11) provides support and positioning for the dental prosthesis solid model (10) in the lower mold box (20). S3. Inject the first molding material into the cavity in the lower mold box (20) and cure it. Remove the diagnostic denture solid model (10) and form a negative mold (30) with tooth grooves (31) in the lower mold box (20). S4. Insert each finished tooth (40) into the tooth groove (31) of the female mold (30) in sequence; S5. The upper molded box (50) with a cavity is sealed and fastened to the lower molded box (20). The upper molded box (50) is provided with a second positioning groove (51). After the second molding material is injected into the cavity of the upper molded box (50) and cured, a personalized resin disc (60) is formed that is tightly combined with the finished tooth (40). During the injection molding process, the second molding material is poured into the second positioning groove (51) to form a second positioning post (61). S6. Open the upper mold box (50) and take out the personalized resin plate (60) with the second positioning post (61) and closely fits the finished dental arch; S7. Fix the personalized resin disc (60) on the rotatable clamp (70) of the cutting device (80). The clamp (70) is provided with a third positioning groove (71) that cooperates with the second positioning post (61). The second positioning post (61) provides support and positioning for the personalized resin disc (60) on the clamp (70). S8. Start the cutting device (80) to cut the personalized resin plate (60) to form a polished surface of the denture. Then remove the personalized resin plate (60) and trim the edges to finally form a complete denture worn in the mouth.

2. The method for fabricating a digital complete denture as described in claim 1, characterized in that, In step S1, a three-dimensional model of a complete denture with a first positioning post (11) is digitally designed, and a solid model (10) of a diagnostic denture with the first positioning post (11) is printed in one piece; or After printing out the diagnostic denture solid model (10), the prefabricated first positioning post (11) is fixedly installed on the diagnostic denture solid model (10).

3. The method for fabricating a digital complete denture as described in claim 1, characterized in that, The diagnostic denture solid model (10) is provided with at least 3 first positioning posts (11) on the same plane, and the upper end surface of the lower mold box (20) is provided with 3 first positioning grooves (21) in different directions for accommodating each of the first positioning posts (11).

4. The method for fabricating a digital complete denture as described in claim 3, characterized in that, The upper molded box (50) has a diameter similar to that of the lower molded box (20). The upper molded box (50) has three second positioning grooves (51) on its snap-fit ​​end face for engaging with the lower molded box (20) and engaging with the first positioning groove (21). In step S5, during the injection molding process, the second molding material is simultaneously poured into the first positioning groove (21) and the second positioning groove (51) to form the second positioning post (61).

5. The method for fabricating a digital complete denture as described in claim 1, characterized in that, The upper molded box (50) and the lower molded box (20) are detachably and sealed together by means of a clamp (70) or a buckle.

6. The method for fabricating a digital complete denture as described in claim 1, characterized in that, The upper mold box (50) is provided with an injection port (52) and at least one vent port (53) on both sides, which are connected to the internal cavity of the upper mold box (50).

7. The method for fabricating a digital complete denture as described in claim 1, characterized in that, In step S3, agar is used as the first molding material to injection mold a female mold (30) with tooth grooves (31). In step S5, acrylic resin is used as the second molding material to injection mold the personalized resin disc (60).

8. The method for fabricating a digital complete denture as described in claim 1, characterized in that, The upper molded box (50) has a thickness-oriented graduated groove in its cavity to form a thickness scale (62) on the side of the personalized resin plate (60).

9. An injection mold for the manufacturing method of the digital complete denture according to any one of claims 1-8, characterized in that, The injection mold is composed of an upper mold box (50) and a lower mold box (20) that are sealed and fastened together. The upper mold box (50) and the lower mold box (20) are provided with injection cavities with opposite openings. The upper mold box (50) and the lower mold box (20) are respectively provided with a first positioning groove (21) and a second positioning groove (51). A female mold (30) with tooth grooves (31) is formed by injection molding in the cavity of the lower mold box (20), and a personalized resin disc (60) that is tightly bonded to the finished tooth (40) is formed by injection molding in the cavity of the upper mold box (50).

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