A novel mandibular prosthesis based on 3D printing

Abstract

The present invention discloses a novel mandibular prosthesis based on 3D printing, which includes a prosthesis main body, an implant abutment, and a fixing component. The implant abutment is arranged on the top surface of the prosthesis main body, and the fixing component is used to connect the prosthesis main body with the first and second mandibles. The fixing component includes a fastening screw, an embedded nut, and an expansion sleeve. Reserved holes are formed on the contact surfaces of the first and second mandibles and the prosthesis main body. The expansion sleeve is placed in the reserved holes, and the embedded nut is screwed into the expansion sleeve. And the expansion sleeve deforms under the extrusion of the embedded nut so as to be tightened in the reserved holes. Connecting holes are arranged on both sides of the prosthesis main body corresponding to the reserved holes. The fastening screw is screwed into the connecting holes, and the end of the fastening screw is fixedly connected with the embedded nut. By utilizing the characteristics of 3D printing technology, the present invention can reasonably design the structures of the mandibular prosthesis fixing device and the implant abutment, with simple structure, quick installation, good stability, and at the same time can improve the convenience and success rate of the operation.

Description

Technical Field

[0001] The present invention relates to the technical field of medical prostheses, and particularly relates to a novel mandibular prosthesis based on 3D printing. Background Art

[0002] Surgical treatment of advanced mandibular tumors will cause large mandibular defects, which not only affect the appearance of patients, but also cause abnormalities in functions such as chewing, swallowing, and speech. Therefore, mandibular reconstruction surgery needs to be carried out. Currently, the most widely used mandibular reconstruction surgery uses autogenous free bone flaps, such as fibula flaps, iliac bone flaps, etc., which have the following main disadvantages. First, the size of the free bone flap depends on the subjective experience of the doctor, and it is difficult to ensure the accuracy during osteotomy of the transplanted bone. Moreover, the shape of the free bone flap itself is quite different from that of the mandible. Therefore, the appearance and function after reconstruction are often quite different from those before the disease. Second, the free bone flap is fixed to the residual mandible with titanium nails and titanium plates, with poor stability, and it will cause damage to the bone cortex at the residual end of the mandible, and osteomyelitis is likely to occur after surgery. Third, there are also great limitations in implanting teeth on the free bone flap after surgery, which is difficult to achieve and cannot solve the impact of tooth loss on the quality of life of patients. Finally, there is a secondary defect in the donor area of the free bone flap, which also affects the quality of life of patients. Other reconstruction schemes include allogeneic bone transplantation, biological material reconstruction, simple titanium plate reconstruction, etc., which also have disadvantages such as immature technology and poor reconstruction effect. Summary of the Invention

[0003] The technical problem to be solved by the embodiments of the present invention is to provide a novel mandibular prosthesis based on 3D printing, which can reasonably design the structures of the fixing device and the dental implant abutment of the mandibular prosthesis by using the characteristics of 3D printing technology, with simple structure, quick installation, good stability, and at the same time can improve the convenience and success rate of the surgery.

[0004] To achieve the above object, the present invention discloses a novel mandibular prosthesis based on 3D printing, including a prosthesis main body, a dental implant abutment, and a fixing component. The prosthesis main body is used for being implanted between a first mandible and a second mandible. The dental implant abutment is arranged on the top surface of the prosthesis main body. The fixing component is used for connecting the prosthesis main body with the first mandible and the second mandible.

[0005] The fixing component includes a fastening screw, an embedded nut, and an expansion sleeve. Reserved holes are provided on the contact surfaces of the first mandible and the second mandible with the prosthesis main body. The expansion sleeve is placed in the reserved holes, and the embedded nut is screwed into the expansion sleeve. And the expansion sleeve deforms under the extrusion of the embedded nut to expand and tighten in the reserved holes. A porous structure is 3D printed on the surface of the expansion sleeve. Connecting holes are provided on both sides of the prosthesis main body corresponding to the reserved holes. The fastening screw is screwed into the connecting holes, and the end of the fastening screw is fixedly connected to the embedded nut, which improves the stability of the embedded nut in the reserved hole position of the non-lesioned mandibular medullary cavity and realizes the hidden fastening of the prosthesis main body with the first mandible and the second mandible.

[0006] Furthermore, a chute is provided on the prosthesis main body. The chute communicates with the connecting hole. A pin shaft is provided on the inner wall of the connecting hole. A spiral groove is provided on the rear section of the fastening screw and is slidably matched with the pin shaft. A push plate is provided on the chute. The rear end of the fastening screw abuts against the surface of the push plate. By pushing the fastening screw in the direction of the embedded nut, the fastening screw makes a rotational forward movement under the action of the pin shaft. An external thread is provided on the front section of the fastening screw, so that the fastening screw is threadedly connected with the embedded nut, making the installation between the prosthesis main body and the first mandible and the second mandible faster. And the hidden design of the fixing component can better avoid the occurrence of osteomyelitis after surgery.

[0007] Furthermore, the fixing component further includes a fixing block. The fixing block is embedded in the chute, so that the chute in the prosthesis main body is hidden, thereby ensuring that the surface of the prosthesis main body is flat without any grooves or holes, making the appearance effect of the patient's maxillofacial region better after implantation. And a shaft hole is provided on the inner side surface of the chute. A counterbore is provided on the fixing block. A jack is provided on the side wall of the fixing block corresponding to the shaft hole and communicates with the counterbore. A plug shaft is inserted into the jack, and one end of the plug shaft extends into the shaft hole, thereby restricting the fixing block in the chute and preventing the fixing block from detaching from the prosthesis main body or shaking.

[0008] Furthermore, a rotary cover is screwed in the counterbore to block the jack in the counterbore, thereby preventing the plug shaft from falling off from the shaft hole and the jack, and ensuring the reliable connection between the fixing block and the prosthesis main body.

[0009] Furthermore, the end of the expansion sleeve is a closed end. A cross-shaped groove is provided on the end face of the closed end. And a plurality of flanges are axially spaced on the outer periphery of the closed end, so that the connection between the expansion sleeve and the first mandible and the second mandible is more firm.

[0010] Further, the thickness of the porous structure is 0.1 mm - 10 mm, and the material of the porous structure is titanium alloy, so that the surface of the expansion sleeve has good osteocyte adhesion and biological activity, thereby promoting the growth of blood vessels and tissues, being conducive to bone tissue regeneration, and enabling the expansion sleeve to fuse with the first mandible and the second mandible.

[0011] Further, guide plates are arranged on both sides of the prosthesis main body, and the guide plates are U-shaped and match the shapes of the first mandible and the second mandible, enabling the prosthesis main body to better fit with the first mandible and the second mandible.

[0012] Further, the dental implant abutment includes an angled abutment and a vertical abutment. The vertical abutment is arranged on both sides of the top surface of the prosthesis main body, and the angled abutment is arranged between the vertical abutments. The distance between the angled abutment and the vertical abutment is 3 mm - 4.5 mm, and the inclination angle of the angled abutment is 65° - 75°.

[0013] Further, a plurality of concave surfaces are arranged at intervals along the axial direction at the lower parts of the angled abutment and the vertical abutment, and dental implant holes are arranged in the angled abutment and the vertical abutment from the top surface towards the inside, thereby enhancing the acting surface for combining with the dental implant.

[0014] Further, the materials of the prosthesis main body, the dental implant abutment, and the fixing assembly are Ti6Al4V-ELI, medical ceramics, carbon fiber, and PEEK, and are manufactured by 3D printing technology.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] (1) The hidden design of the fixing device of the present invention, compared with the traditional direct external titanium nail fixed connection with the residual mandible, after the prosthesis main body is implanted, the maxillofacial appearance and oral function of the patient can be restored to the state before the disease to the greatest extent, and all structures are manufactured by 3D printing technology, making the prosthesis main body consistent with the resected mandible in shape, reducing the damage to the residual mandibular body, enhancing its stability after reconstruction, and at the same time improving the convenience and success rate of the operation. (2) The expansion sleeve covered with a porous structure on the outer layer improves the stability of the embedded nut in the reserved hole position of the non-lesioned mandibular medullary cavity, avoiding the occurrence of osteomyelitis after the operation. (3) The present invention adopts a two-stage fastening screw design with a threaded front end for fixation and a spiral groove at the rear end for propulsion, and a pin shaft is designed in the connection hole of the prosthesis main body, which can not only realize the rotational forward movement of the fastening screw but also play a role in connecting and fastening. (4) The prosthesis main body and the implant abutment are integrally formed by 3D printing technology, reducing the assembly process of the implant abutment and providing conditions for subsequent tooth implantation. Description of the Drawings

[0017] Figure 1 Front view of the overall structure of the present invention;

[0018] Figure 2 Side view of the overall structure of the present invention;

[0019] Figure 3 Front view of the overall structure of the prosthesis main body;

[0020] Figure 4 Stereogram of the overall structure of the prosthesis main body;

[0021] Figure 5 Schematic diagram I of the states of the first and second mandibles;

[0022] Figure 6 Schematic diagram II of the states of the first and second mandibles;

[0023] Figure 7 Schematic diagram of the overall structure of the fastening screw;

[0024] Figure 8 Schematic diagram of the overall structure of the embedded nut;

[0025] Figure 9 Schematic diagram of the overall structure of the expansion sleeve;

[0026] Figure 10 Cross-sectional view of the overall structure of the expansion sleeve;

[0027] Figure 11 Schematic diagram of the overall structure of the hidden design of the present invention;

[0028] Figure 12 Schematic diagram of the overall structure of the fixing block;

[0029] Figure 13 Partially enlarged schematic diagram of the sliding hole;

[0030] Figure 14 Side view of the overall structure of the angle abutment;

[0031] Figure 15 Front view of the overall structure of the vertical abutment. Detailed implementation manners

[0032] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0033] Refer to Figure 1 、 Figure 3 、 Figure 5As shown, a novel mandibular prosthesis based on 3D printing includes a prosthesis main body 1, an implant abutment 2, and a fixing component 3. In this embodiment, after removing a part of the diseased or damaged mandible (in this embodiment, the diseased mandible part between the first mandible 10 and the second mandible 20 is removed for illustration), the prosthesis main body 1 is customized by 3D printing technology according to the shape of the removed mandible part. Then, the prosthesis main body 1 is implanted between the first mandible 10 and the second mandible 20. Guide plates 13 are provided on both sides of the prosthesis main body 1. The guide plates 13 are U-shaped and match the shapes of the first mandible 10 and the second mandible 20, so that the guide plates initially fix the matching of the prosthesis main body 1 with the first mandible 10 and the second mandible 20, and the prosthesis main body 1 is connected to the first mandible 10 and the second mandible 20 through the fixing component 3, thereby ensuring that the prosthesis main body 1 is consistent with the removed mandible 10 in shape, and after implantation, the facial appearance and oral function of the patient can be restored to the state before the disease to the greatest extent. The implant abutment 2 is arranged on the top surface of the prosthesis main body 1, and the implant abutment 2 and the prosthesis main body 1 are integrally formed by 3D printing technology, reducing the assembly process of the implant abutment 2, providing conditions for subsequent tooth implantation, making the installation faster, and improving the convenience of the operation.

[0034] In this embodiment, the material of the prosthesis main body 1 is Ti6Al4V-ELI, medical ceramics, carbon fiber, PEEK, etc. Preferably, Ti6Al4V-ELI is used. This material not only has high strength, light weight, strong corrosion resistance, but also has good biocompatibility.

[0035] Refer to Figures 7 - 9 Further, the fixing component 3 includes a fastening screw 31, an embedded nut 32, and an expansion sleeve 33. Before implanting the prosthesis main body 1, in this embodiment, a reserved hole 30 is opened on the contact surfaces of the first mandible 10, the second mandible 20 and the prosthesis main body 1 (i.e., the mandibular medullary cavity) (as Figure 5 shown). The diameter of the reserved hole 30 is 10.30 mm, and the depth is 12 mm. Then, the expansion sleeve 33 is inserted into the reserved hole 30. In this embodiment, the first end of the expansion sleeve 33 is an open end, and its second end is a closed end 331. The outer diameter of the expansion sleeve 33 gradually decreases from the open end along the direction of the closed end 331, and the outer diameter of the open end of the expansion sleeve is slightly larger than the inner diameter of the reserved hole 30, so that after the expansion sleeve 33 is implanted into the first mandible 10 and the second mandible 20, its open end is in interference fit with the reserved hole 30, preventing the expansion sleeve 33 from rotating in the reserved hole 30 and affecting the subsequent fixation. A cross groove 332 is opened on the end surface of the closed end 331, and the embedded nut 32 is screwed into the expansion sleeve 33 through a flat-blade screwdriver (as Figure 6As shown in the figure, in this embodiment, the length of the embedded nut 32 is 10 mm - 12 mm, the outer ring has an M10 thread, and the inner ring has an M5 thread. Thus, the closed end 331 of the expansion sleeve 33 deforms under the extrusion of the embedded nut 32, so that the expansion sleeve 33 is tightened in the reserved hole 30. And a plurality of flanges 333 are arranged at intervals along the axial direction on the outer periphery of the closed end 331, so that the connection between the expansion sleeve 33 and the first mandible 10 and the second mandible 20 is more firm. And connection holes 11 are arranged on both sides of the prosthesis main body 1 corresponding to the reserved holes 30. The fastening screw 31 is screwed into the connection hole 11 and fixedly connected to the embedded nut 32 through the head end of the fastening screw 31, so as to fix the prosthesis main body 1 on the first mandible 10 and the second mandible 20.

[0036] The specific dimensions of the above-mentioned embedded nut 32 and expansion sleeve 33 can be modified according to the actual situation of the patient, and are not limited to the above values, so no repetitive description is made here.

[0037] Refer to Figure 8 、 Figure 10 As shown, more preferably, the surface of the expansion sleeve 33 is 3D printed with a porous structure 5 by SLM technology. The thickness of the porous structure 5 is 0.1 mm - 10 mm, and a thickness of 0.5 mm is preferably adopted in this embodiment. And the porosity and pore size on the surface of the porous structure 5 are designed according to the most suitable bone fusion ability, so that the surface of the expansion sleeve 33 has good osteocyte adhesion and biological activity, thereby providing more growth space, promoting the growth of blood vessels and tissues of the first mandible and the second mandible, being beneficial to bone tissue regeneration, making the connection between the expansion sleeve 33 and the first mandible 10 and the second mandible 20 more stable, and improving the stability of the embedded nut 32 in the reserved holes 30 of the non-lesioned first mandible 10 and second mandible 20. In this embodiment, the material of the porous structure 5 is preferably titanium alloy, so as to promote the bone fusion ability.

[0038] Further preferably, in this embodiment, the surface of the porous structure 5 of the expansion sleeve 33 can be improved in surface wear resistance by adding a coating, or can be post-treated to improve its bone fusion ability.

[0039] Combined with Figure 2 、 Figure 3As shown in the figure, further explanation is as follows. A sliding groove 12 is provided on the prosthesis main body 1. The sliding groove 12 communicates with the connecting hole 11. A pin shaft 111 is provided on the inner wall of the connecting hole 11. In this embodiment, the length of the fastening screw 31 is 16.5 mm. The front section of the fastening screw 31 is provided with an external thread 312, and its length is 6.5 mm. The surface of the rear section of the fastening screw 31 is provided with a spiral groove 311, which slidably cooperates with the pin shaft 111. A push plate 4 is provided on the sliding groove 12. The push plate 4 can slide parallel to the sliding groove 12, and the end surface of the push plate 4 has a concave position 41. Before implanting the prosthesis main body 1 into the first mandible 10 and the second mandible 20, the fastening screw 31 enters from the outer end of the connecting hole 11 (i.e., the end adjacent to the reserved hole 30), and the fastening screw 31 is screwed into the sliding groove 12 through a flat-blade screwdriver until the end of the fastening screw 31 abuts against the concave position 41 of the push plate 4.

[0040] Subsequently, the prosthesis main body 1 is implanted between the first mandible 10 and the second mandible 20, and the guide plate 13 of the prosthesis main body 1 is used to perform initial fixation matching with the first mandible 10 and the second mandible 20. The push plate 4 is used to push the fastening screw 31 to move forward in the direction of the embedded nut 32. In this embodiment, the angle between the spiral line of the spiral groove 311 and the axis of the fastening screw 31 is 40° - 60°, preferably 45°, so that the fastening screw 31 makes a rotational forward movement under the cooperation of the spiral groove 311 and the pin shaft 111, and the external thread 312 of the fastening screw 31 is threadedly connected with the embedded nut 32, thereby fixedly connecting the prosthesis main body 1 with the first mandible 10 and the second mandible 20, making the connection of the prosthesis main body 1 more firm, and thus realizing the hidden fastening of the prosthesis main body 1 with the first mandible 10 and the second mandible 20.

[0041] Refer to Figures 11 - 13 As shown in the figure, in this embodiment, the fixing component 3 further includes a fixing block 34 that matches the shape of the sliding groove 12. A shaft hole 121 is opened on the inner side surface of the sliding groove 12, and a counterbore 341 is opened on the fixing block 34. A jack 342 that communicates with the counterbore 341 is provided on the side wall of the fixing block 34 corresponding to the shaft hole 121. A plug shaft 343 is inserted into the jack 342. In this embodiment, the length of the plug shaft 343 is greater than the length of the jack 342, so that one end of the plug shaft 343 extends into the shaft hole 121, thereby restricting the fixing block 34 within the sliding groove 12 and preventing the fixing block 34 from detaching from or shaking in the prosthesis main body 1.

[0042] Specifically, in this embodiment, the sliding groove 12 is not limited to opening the shaft hole 121 on one surface. The shaft hole 121 can also be opened on the inner top surface and the inner bottom surface of the sliding groove 12, so as to make the connection between the fixing block 34 and the prosthesis main body 1 more firm.

[0043] Further, a rotary cap 344 is fixedly connected inside the sunk groove 341. In this embodiment, a screw rod is provided on the rotary cap 344, and a threaded hole threaded with the screw rod is provided in the sunk groove 341, so that the rotary cap 344 blocks the jack 342 in the sunk groove 341, thereby preventing the insertion shaft 343 from falling off from the shaft hole 121 and the jack 342, so as to ensure a reliable connection between the fixing block 34 and the prosthesis main body 1.

[0044] Through the above settings, the chute 12 and the connection hole 11 are hidden by the fixing block 34, so as to ensure that the surface of the prosthesis main body 1 is flat without any grooves or holes, making the appearance effect of the patient's maxillofacial region better after implantation.

[0045] Furthermore, it should be noted that in this embodiment, the fastening screw 31, the embedded nut 32, the expansion sleeve 33, the fixing block 34, the rotary cap 344 and the insertion shaft 343 are all manufactured by 3D printing technology.

[0046] Refer to Figure 1 、 Figure 4 As shown, the dental implant abutment 2 includes an angled abutment 21 and a vertical abutment 22. The vertical abutment 22 is arranged on both sides of the top surface of the prosthesis main body 1, and the angled abutment 21 is arranged between the vertical abutments 22. In this way, the teeth are implanted on the angled abutment 21 and the vertical abutment 22 by means of bonding. In this embodiment, the angled abutment 21 and the vertical abutment 22 are integrally formed with the prosthesis main body 1, reducing the assembly process of the implant abutment and providing conditions for subsequent tooth implantation, thereby improving the convenience of the operation.

[0047] Combined with Figure 14 、 Figure 15 As shown, the distance between the angled abutment 21 and the vertical abutment 22 is 3 mm - 4.5 mm, so as to prevent the teeth implanted on the angled abutment 21 and the vertical abutment 22 from being crowded with each other. The inclination angle of the angled abutment 21 is 65° - 75°, so as to ensure the beauty and naturalness of the teeth after implantation, and be able to withstand the force generated by daily chewing, avoiding loosening or failure in the later stage, and the implanted teeth are more beautiful. The lower parts of the angled abutment 21 and the vertical abutment 22 are provided with a plurality of concave surfaces 23 at intervals along the axial direction, and the angled abutment 21 and the vertical abutment 22 are provided with dental implant holes 24 from the top surface to the inside, so as to enhance the contact surface for combining with the dental implant.

[0048] The above specific dimensions can be modified according to the actual situation of the patient and will not be repeated here.

[0049] Of course, the above embodiments are only used to illustrate the technical concept and characteristics of the present invention, and their purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly. It should not be used to limit the protection scope of the present invention. All modifications made according to the spirit of the main technical solution of the present invention should be covered within the protection scope of the present invention.

Claims

1. A new mandibular prosthesis based on 3D printing, characterized in that: The invention comprises a prosthesis body (1), a dental implant base (2), and a fixing assembly (3), wherein the prosthesis body (1) is used to be implanted between a first mandible (10) and a second mandible (20), the dental implant base (2) is arranged on the top surface of the prosthesis body (1), and the fixing assembly (3) is used to connect the prosthesis body (1) and the first mandible (10) and the second mandible (20); The fixing assembly (3) comprises a fastening screw (31), an embedded nut (32), and an expansion sleeve (33); a reserved hole (30) is provided on the contact surface between the first mandible (10), the second mandible (20) and the prosthesis main body (1); the expansion sleeve (33) is placed in the reserved hole (30); the embedded nut (32) is screwed into the expansion sleeve (33); and the expansion sleeve (33) is deformed under the pressure of the embedded nut (32) so as to be expanded and tightened in the reserved hole (30); a porous structure (5) is 3D printed on the surface of the expansion sleeve (33); connecting holes (11) are provided on both sides of the prosthesis main body (1) corresponding to the reserved holes (30); the fastening screw (31) is screwed into the connecting hole (11), and the end of the fastening screw (31) is fixedly connected to the embedded nut (32); A pin shaft (111) is provided on the inner wall of the connecting hole (11), a spiral groove (311) is provided on the rear section of the fastening screw (31) and is slidably matched with the pin shaft (111), and the fastening screw (31) is pushed to move in the direction of the embedded nut (32), so that the fastening screw (31) performs a rotational forward movement under the action of the spiral groove (311) and the pin shaft (111), and an external thread (312) is provided on the front section of the fastening screw (31), so that the fastening screw (31) and the embedded nut (32) are threadedly connected; The prosthesis body (1) is provided with a slide groove (12), the slide groove (12) is connected to the connecting hole (11), and a push plate (4) is provided on the slide groove (12), the rear end of the fastening screw (31) abuts against the surface of the push plate (4), and the fastening screw (31) is pushed forward by the push plate (4).

2. The novel mandibular prosthesis based on 3D printing according to claim 1, characterized in that: The fixing assembly (3) further comprises a fixing block (34), the fixing block (34) being embedded in the slide groove (12), and the inner side surface of the slide groove (12) being provided with an axial hole (121), the fixing block (34) being provided with a sink groove (341), and a side wall of the fixing block (34) being provided with a plug hole (342) in communication with the sink groove (341) corresponding to the axial hole (121), an insert shaft (343) being inserted into the plug hole (342), and one end of the insert shaft (343) extending into the axial hole (121).

3. The novel mandibular prosthesis based on 3D printing according to claim 2 is characterized in that: A rotary cover (344) is screwed into the sink (341) so that the rotary cover (344) blocks the insertion hole (342) in the sink (341).

4. The novel mandibular prosthesis based on 3D printing according to claim 1, characterized in that: The end of the expansion sleeve (33) is a closed end (331), an end surface of the closed end (331) is provided with a cross slot (332), and a plurality of flanges (333) are provided at intervals along the axial direction on the outer periphery of the closed end (331).

5. The novel mandibular prosthesis based on 3D printing according to claim 1, characterized in that: The thickness of the porous structure (5) is 0.1 mm-10 mm, and the material of the porous structure (5) is titanium alloy.

6. The novel mandibular prosthesis based on 3D printing according to claim 1, characterized in that: Guide plates (13) are provided on both sides of the prosthesis body (1), and the guide plates (13) are U-shaped and match the shapes of the first mandible (10) and the second mandible (20).

7. The novel mandibular prosthesis based on 3D printing according to claim 1, characterized in that: The dental implant base (2) comprises an angle base (21) and a vertical base (22), wherein the vertical base (22) is arranged on both sides of the top surface of the prosthesis body (1), and the angle base (21) is arranged between the vertical bases (22), the spacing between the angle base (21) and the vertical base (22) is 3 mm-4.5 mm, and the inclination angle of the angle base (21) is 65°-75°.

8. The novel mandibular prosthesis based on 3D printing according to claim 7, characterized in that: A plurality of concave surfaces (23) are arranged at intervals along the axial direction at the lower part of the angle base (21) and the vertical base (22), and a tooth implant hole (24) is arranged from the top surface to the inside of the angle base (21) and the vertical base (22).

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