JP3713318B2 - Artificial tooth root - Google Patents

Description

[0001]
[Industrial application fields]
The disclosed technology belongs to the technical field of a structure in which an artificial tooth root as an implant made of titanium or titanium alloy is embedded in the jawbone in the oral cavity.
[0002]
[Prior art]
As is well known, human teeth are deeply involved in vital functions such as eating, vocalization and expression in the oral cavity. Therefore, loss of teeth due to defects or the like may impair these functions. It becomes a fatal problem.
[0003]
Therefore, in order to compensate for such missing teeth such as missing teeth, we have dealt with by treating the teeth close to the missing teeth, but recently, the loss of neighboring teeth, traffic accidents, major diseases, etc. In the case where multiple adjacent teeth are lost due to the above, a technique for embedding an artificial root as an implant made of titanium or titanium alloy in the jawbone in the oral cavity has been developed, and some have been put into practical use .
[0004]
[Problems to be solved by the invention]
As for such a technique, for example, an excellent technique like the invention disclosed in Japanese Patent Application Laid-Open No. 1-111539 (Japanese Patent Publication No. 7-71563) has been developed. In the case of a tooth root, the leg part embedded in the jawbone and the head part for maintaining the upper prosthesis and the leg part penetrating the mucous membrane between them are integrated, or a part of the neck part is the head part. However, the following problems have arisen.
[0005]
Thus, it is indispensable to acquire a strong integral bond (oseointegration) with the jawbone for implanting in the jawbone. It has been known that it takes a long time of several months. Therefore, the occlusal pressure at the time of eating or voicing is applied within the long period from the initial placement in the jawbone to the acquisition. It has been found that it is not preferable for the growth of bone buds, and that even the weight of the denture of the prosthesis of the head is not preferable. Therefore, the artificial root of the implant is embedded in the jawbone. In the case of an integral structure from the leg portion to the prosthesis of the head, there is a disadvantage that it is not preferable due to the application of the occlusal pressure and the like.
[0006]
In addition, strong oseointegration is not only the above-mentioned structural problem after implant placement, but even if a structure that does not apply occlusal pressure by some means is obtained, the prosthesis of the head as an implant structure on the mucous membrane The protrusion of the object supporting part has an unfavorable disadvantage from the viewpoint of infection after the treatment.
[0007]
That is, in the conventional structure of the monolithic implant, since the head protrudes integrally through the mucous membrane, there is a difficulty in infecting the lower part through the neck of the implant after the operation.
[0008]
Furthermore, the operation for implanting the implant starts with the incision of the mucous membrane and ends with the suture. The incision operation is extremely important for preventing infection, and inevitably two or more operations are required. Along with this, in order to prevent infection, it is extremely important to make an incision avoiding the site of implant placement, and of course there should be no structure protruding above the mucosa. Is preferable.
[0009]
And the original purpose of the implant is not to embed the implant in the jawbone, but to use it to make the superstructure of the prosthesis, and the superstructure varies depending on the patient, It differs depending on the patient's adjacent teeth and interdental teeth, also varies with the passage of time after implantation, i.e., with increasing age, and adapts to the implantation site and timing in the patient's jawbone. "Mucosal penetration part" and "prosthesis support part" are necessary.
[0010]
To that end, the “implanted part in the jawbone”, “penetrating mucosa”, and “prosthesis support part” must be separable into three independent parts. However, there is a disadvantage that cannot be adopted in the conventional artificial implant root of a monolithic structure.
[0011]
The prosthesis is designed to enable the selective replacement and the like of the joint structure of the intraosseous implant part, the mucosal penetration part, and the prosthesis support part, and the optimal prosthesis suitable for the patient, along with the clinical course. In spite of the need for a structure in which the object support portion can be replaced independently, there is a negative point that cannot be applied to the artificial tooth root of the conventional implant.
[0012]
In addition, the implant of artificial implant root of “implanted part in jawbone” and “mucosal penetration part” or “prosthesis support part” of the two-part split type implant in which the neck and head can be separated from the leg part. Even in the case of an artificial tooth root, there is a problem that the above-described “intramaxillary implant”, “mucosa penetrating part”, and “prosthesis support part” cannot cope with various conditions.
[0013]
In the conventional mode disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 1-111539 (Japanese Patent Publication No. 7-71563), etc., the leg part and the leg part or the head part are formed by so-called uneven engagement. Due to the integrated connection structure, it is insufficient to cope with the clinically applied occlusal pressure, and the joint part is shaken by the occlusal pressure, resulting in the prosthesis being shaken and the function as an artificial tooth root. There was a problem that it was not satisfactory.
[0014]
OBJECT OF THE INVENTION
The object of the invention of this application is to apply structurally, anatomically and clinically enough, while developing an excellent artificial tooth root technology for implants to deal with natural tooth defects based on the above-mentioned prior art. It is a technical problem to solve the problems of unintegrated monoliths or artificial roots with a two-part structure. The surgeon can easily place the implant in the jawbone and the incision of the mucosal penetration part is extremely smooth. It is possible to prevent infections as much as possible, and after implantation, it is possible to eat semi-permanently as designed and to ensure occlusion by occurrence, etc. It is intended to provide an artificial tooth root.
[0015]
[Means and actions for solving the problems]
In order to solve the above-mentioned problem, the structure of the invention of the present application, which is summarized in the scope of the above-mentioned claims along with the above-mentioned object, is to provide a leg of an artificial tooth root when an artificial tooth root of an implant for a missing tooth is embedded in a jawbone. The intermaxillary implant part as the upper part and the upper prosthesis support part are integrally inserted between the two, and the mucous membrane penetration part as the neck part can be connected and separated freely by mutual screw connection. Therefore, the surface of the side of the implant in the jaw bone forms a discharge mark having an average roughness of 5 μm or more by wire-cut electric discharge machining, and it is ensured when the leg is embedded in the jaw bone. The acquisition of oseointegration is achieved, and the calcium phosphate-based ceramic coating makes it easy to adapt to the jawbone and to improve osteogenesis. Two or more notch-type grooves are engraved on the tip, or plate-like projections are formed to ensure secure eoeointegration, and even after application of occlusion, etc. The mucous membrane penetration part is used as a receiving part so that there is no wobbling of the leg part, and the joint between the jawbone implant and the mucous membrane penetration part is screwed to prevent rotation due to rotational torque at the time of screw tightening or disengagement. The bottom part of the body has a polygonal shape of three or more corners to form an anti-rotation structure part, and the upper part thereof is formed into a circular cross section to form a load-bearing structure part against horizontal stress, and the mucous membrane penetration part and prosthesis The connection with the support part is a double-stage screw structure, and when the prosthesis support part is connected to the mucosal penetration part, the screw is tightened or prevented from rotating due to dissociation, and the mucosal penetration part of the prosthesis support part Against When screw is connected, the mucous membrane penetration part is fixed in a fixed state with a nut, wrench, etc., and it is securely tightened and dissociated, and good oseointegration acquisition and prosthetic support part contribute to the clinical course of the patient. In addition, technical measures were taken so that they can be selectively exchanged as needed, and sufficient oseointegration acquisition and good maintenance maintenance can be achieved by the generation of osteoblasts as designed.
[0016]
【Example】
Next, an embodiment of the invention of this application will be described with reference to the drawings.
[0017]
Note that the same reference numerals are used for the same mode parts throughout the drawings.
[0018]
In the aspect of each embodiment, the artificial tooth root is made of titanium or a titanium alloy.
[0019]
The embodiment shown in FIG. 1 to FIG. 6 is a basic mode, 1 is an artificial dental root as an implant which forms the center of the gist of the present invention, and the artificial dental root 1 is in the lower jaw bone as a leg. It is a rod-like body composed of three parts, an implantable part 2, a mucous membrane penetration part 3 as a neck part of the middle part, and a prosthesis support part 4 as an upper part of the head. It is designed to be separably integrated with the body.
[0020]
The jaw bone implant 2 is embedded in the jaw bone 6, and the surface of the side part from the middle part to the tip part has an average roughness of 5 μm or more (ideally, the average roughness is 15 to 25 μm. Has been experimentally found to be preferable)), or a calcium phosphate ceramic coating.
[0021]
It has been experimentally found that by forming in this way, reliable acquisition of oseointegration can be achieved in a short period of time due to good growth of osteoblasts with the jawbone 6.
[0022]
Then, three notch-shaped grooves 7 are formed by wire-cut electric discharge machining in the circumferential direction from the midway part to the distal end part of the jawbone implant part 2, and an overhang-like cover is formed in the midway part of the groove 7 from both sides. 8 is integrally formed and firmly integrated with the jawbone 6 as the osteoblast grows, and the strength against rotational stress, horizontal stress and vertical stress can be increased, and the contact area with the jawbone 6 is increased. The initial effective Oseo integration can be obtained very easily.
[0023]
In addition, in order to obtain strong oseointegration with the jawbone 6, a structure without local stress concentration on the jawbone 6 is necessary, and the groove 7 is not a stepped structure in the longitudinal direction, but at the tip portion. It is formed in a shape that concentrates.
[0024]
The mucosa penetrating part 3 with respect to the mucous membrane 9 is rotated at the joint part 10 with respect to the intramaxillary implant part 2 in the clinically applied occlusal pressure having a hexagonal tip as shown in FIGS. A polygonal portion 11 for preventing rotation against stress and a load-bearing structure portion 12 having a circular cross section with respect to a horizontal component force when the bite is applied are integrally formed on the upper portion, and a tapered shape is formed on the upper portion. A mucous membrane penetrating part main body 13 is formed, and a flat section hexagonal receiving part 14 is formed for coping with the generation of rotational torque when the upper prosthesis support part 4 is screwed.
[0025]
The mucous membrane penetration portion 3 is concentrically provided with a screw hole 16 for a fixing screw 15 in the coupling portion 10 with respect to the intramaxillary implant portion 2 for coupling the prosthesis support portion 4 to the mucosal penetration portion 3. A female screw 16 'with respect to the male screw 17' of the fixing screw 17 is engraved.
[0026]
Reference numeral 18 denotes a cement fixing formed product as a prosthesis.
[0027]
Reference numeral 4 ′ denotes a hole for tightening the artificial root of the male screw 17 ′ of the fixing screw 17 formed in the upper part of the prosthesis support portion 4.
[0028]
The receiving portion 14 receives a rotational force from a nut and a wrench (not shown) when the fixing screws 15 and 17 are tightened or disengaged with respect to the mucosal penetrating portion 3 of the prosthesis support portion 4 to prevent rotation, thereby ensuring a reliable connection. It is something that can be obtained.
[0029]
In the above-described configuration, the rod-like jaw bone implantation part 2 is inserted into the embedding hole previously formed in the jaw bone 6 through the incision portion for the mucous membrane 9 by the surgeon, and oseointegration with the jaw bone 6 is firmly obtained. Thereafter, the mucosal penetrating part 3 is connected to the intra-mandibular implant part 2 via a fixing screw 15 set by the joint part 10 to integrate them.
[0030]
At this time, as shown in FIG. 1, the fixing screw 15 is screwed into the upper part of the intramaxillary implant 2 and the lower end of the mucosa penetrating part 3 and is connected in two stages. It is not distorted by the application of clinical occlusion over time, and therefore, the acquisition of oseointegration can be sufficiently guaranteed.
[0031]
Alternatively, the mucous membrane 9 is incised by performing the first operation first, and the mucosal penetrating portion 3 is two-staged by the fixing screw 15 with respect to the intramaxillary implantation portion 2 embedded in the insertion hole formed in the jawbone 6. Screw together.
[0032]
At this time, since the fixing screw 15 is screwed in two steps at the joint portion 10 between the mucosal penetration portion 3 and the jawbone implant portion 2, the connection is made tight, and in the clinical course after implantation. Even when stress such as occlusion is applied, loosening, rattling, and the like in the coupling portion 10 are prevented.
[0033]
In addition, since the grooves 7, 7, and 7 in the jawbone implant 2 increase the contact area with the jawbone 6 and the covers 8 and 8 bite into the jawbone 6, the jawbone after implantation is inserted. The initial development of osteoblasts in No. 6 is performed well and is surely achieved in the acquisition of Oseointegration.
[0034]
Then, after the incision with respect to the mucous membrane 9 is performed and the prosthesis support portion 4 with respect to the mucosa penetrating portion 3 is connected and integrated with the male screw 17 'with respect to the screw hole 16, the receiving portion of the mucous membrane penetrating portion 3 is received. 14, the mucosa penetrating portion 3 is prevented from rotating with a nut and wrench (not shown) and is securely fixed, and the nut and wrench (not shown) are engaged with the prosthesis support portion 4 to be firmly attached.
[0035]
In this way, embedding in the gingiva 5 is completed in a state where the three parts of the neck implantation part 2, the mucosal penetration part 3 and the prosthesis support part 4 are integrally connected, and as shown in FIG. 3 and the prosthesis support part 4 are set to a predetermined cement fixation formed article 18 as a prosthesis, and the treatment of the artificial tooth root 1 is completed.
[0036]
Even when occlusal pressure is applied at the time of eating or uttering, and the bruxism of the patient occurs, the prosthesis support part 4, the mucosal penetration part 3, and the jawbone implant part 2 are fixed together. Since the screws 15 and 17 are firmly connected to each other, no looseness or rattling occurs, and the initial acquisition of oseointegration is effectively achieved.
[0037]
Further, even when a rotational force is applied to the joint 10 between the intraosseous implant 2 and the mucosa penetrating part 3 during application of occlusal pressure or bruxism, the hexagonal anti-rotation structure 11 prevents the rotation stress. In addition, the horizontal force associated therewith is surely retained by the oseointegration obtained by the stress distribution being averaged by the load bearing structure portion 12 having a circular cross section.
[0038]
Further, when the prosthesis support 18 is removed from the mucosa penetrating part 3 when the prosthesis cement fixation molding 18 is replaced unexpectedly, the mucous membrane can be removed via a nut or wrench (not shown) with respect to the receiving part 14. By fixing so as to prevent the rotation of the penetrating part 3, it is smoothly performed without losing the oseointegration that has been acquired by screw tightening or disengagement such as removal and remounting.
[0039]
In this embodiment, the intramaxillary implant 2 and the mucosa penetrating portion 3 are firmly and integrally connected to each other through the fixing screw 15 so that the incision at the time of surgery is the optimum site for the mucosa 9. Therefore, there is no risk of infection as described above.
[0040]
In this manner, the intramaxillary implant 2, the mucosa penetrating portion 3, and the prosthesis support portion 4 are firmly and integrally connected via screw connection, and the application of rotational torque is prevented during screw tightening and disengagement. In addition, since the stress action during the tightening or disengagement of the screw is prevented, the initially obtained oseointegration is not impaired, and a groove 7 is formed on the side surface of the jawbone implant 2. Since three bodies are formed in the circumferential direction, the contact area with the jawbone 6 is increased, the initial formation of osteoblasts is performed well, and the grooves 7 are formed uniformly along the circumferential direction. Therefore, the formation of bone buds of the jawbone 6 is stably performed by a structure without stress concentration.
[0041]
Further, since the artificial tooth root 1 is made of titanium or a titanium alloy in terms of material, it does not change in the clinical course after the operation, and therefore no harmful action occurs.
[0042]
This is also fully guaranteed from the results of biological tests, zoological experiments and clinical trials.
[0043]
Further, since the upper surface average roughness of the jawbone implant 2 is 5 μm or more, preferably 15 to 25 μm, it is formed by wire cut discharge trace processing, or because it is formed to have a calcium phosphate ceramic coating. In addition, it is also known from experimental data that since the material is similar to the bone component, the initial osseointegration with the jawbone 6 can be achieved in a very short time.
[0044]
Next, in the embodiment shown in FIG. 7, the intramaxillary implant 2 and the mucosa penetrating portion 3 are connected and integrated by a single fixing screw 15 ', and further, the mucosal penetrating portion 3 and the prosthesis support portion above it. 4 is fixed by a single fixing screw 17 ′, and thus the structure is simple and the connection of the artificial root 1 ′ at the time of operation is integrated. The treatment at the time of replacement of the portion 4 is easier, the treatment is extremely easy, and has the merit of being performed smoothly.
[0045]
In this embodiment, the fixing screw 15 'for connecting the mucosal penetration part 3 to the jaw bone implant 2 and the fixing screw 17' for integrally connecting the prosthesis support part 4 to the mucosal penetration part 3 are used as a kind of lock nut. By double-connecting, the fixing screw 15 ', that is, there is an advantage that the prosthesis penetration part 3 can be reliably prevented from loosening with respect to the jawbone implant part 2.
[0046]
The embodiment shown in FIG. 8 is a mode in which the merits of the above-described embodiments are shared, and the mucosa penetrating portion is connected to the fixing screw 15 ″ for connecting the mucosal penetrating portion 3 to the intramaxillary implant portion 2. 3 is a mode in which the connection screw 4 ″ of the prosthesis support portion 4 to the mucosa penetrating portion 3 is also used, and the treatment is performed more smoothly.
[0047]
Of course, the embodiments of the invention of this application are not limited to the above-described embodiments. For example, the groove has various aspects such as integrally providing a plate-like protrusion opposite to the groove. It can be adopted.
[0048]
【The invention's effect】
As described above, according to the invention of this application, the implant portion and the neck as a leg portion to be embedded in the jawbone while taking full advantage of the artificial tooth root as an implant that is basically developed and put into practical use. The mucosa penetrating part and the prosthetic support part as a part are integrated into one unit via screw connection, so that it can be fully applied to two operations, and in particular, two incisions of the mucous membrane are ensured. It is possible to perform an optimal incision by coping with the different clinical courses of adjacent teeth and counter teeth depending on the patient, and therefore, it is possible to sufficiently prevent infection associated with the incision. An excellent effect is possible.
[0049]
And since the prosthesis support part as the head is integrated with the artificial tooth root through the connection to the mucosa penetrating part, the prosthesis support part can be easily removed during the replacement of the prosthesis with the clinical course. In order to be able to do it, the outstanding effect that the treatment is performed smoothly and easily is produced.
[0050]
In addition, the anti-rotation structure is formed at the bottom of the mucosa penetrating portion to tighten or disengage the screw to the mucosal penetrating portion of the prosthetic support portion. Accordingly, rotation of the implantable portion within the jawbone due to the applied rotational torque can be prevented, and an excellent effect that the prosthesis support portion is attached, fixed, and dissociated with respect to the mucosa penetrating portion is obtained.
[0051]
In addition, by connecting one or two fixing screws at the joint of the mucosa penetrating part to the intramaxillary implant, no loosening or rattling occurs even when the occlusal pressure is applied during the clinical course. There is an effect that the loss of the initial acquired oseointegration is prevented and the function of the artificial root as designed is maintained.
[0052]
In addition, the rotational torque of the occlusal pressure applied to the transmucosal part or the prosthesis support part with respect to the implantable part in the jawbone is rotated by the rotation prevention structure part having a polygonal cross section of a triangle or more below the mucous membrane penetration part. No stress is applied due to torque, and the load-bearing structure part with a circular cross section is formed on the upper part of the polygonal part. From the point that the initial formation of oseointegration to the jawbone of the implanted portion is not lost, an excellent effect of reliably maintaining the state of acquisition of oseointegration is achieved.
[0053]
In addition, since a plurality of grooves are formed along the axial direction on the side surface of the implantable portion of the jawbone, the groove increases the contact area with the jawbone on the side surface of the implantable portion of the jawbone, and the acquired oseointegration is obtained. An excellent effect that can be sufficiently maintained.
[0054]
In addition, the design in which the groove is formed smoothly along the axial direction has the effect of eliminating local stress concentration on the jawbone, and from this point on, the once acquired eoeointegration is reliably maintained. An excellent effect is achieved.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of one embodiment of the invention of this application.
FIG. 2 is a schematic side view of a mucosal penetrating part.
FIG. 3 is a plan view of the same.
4 is a longitudinal sectional view of FIG. 2. FIG.
FIG. 5 is a schematic perspective view of a jawbone implant.
6 is a partial cross-sectional view taken along the line VI-VI in FIG.
FIG. 7 is a schematic cross-sectional view of another embodiment corresponding to FIG.
FIG. 8 is a schematic sectional view of still another embodiment of the present invention.
[Explanation of symbols]
6 jawbone 1, 1 ', 1''artificial tooth root 2 leg (implanted part in jawbone)
3 Neck (mucosal penetration)
4 head (prosthesis support)
9 Mucosal membrane 11 Anti-rotation structure 12 Strength bearing structure 15, 15 ′, 15 ″, 17, 17 ′ Fixing screw 7 Groove 8 Cover 14 Receiving part

Claims (9)

In the artificial tooth root embedded in the jawbone,
The lower jaw implant part, the upper prosthesis support part, and the mucosal penetration part between the two can be separated into three,
It has a concave-convex joint part composed of a concave structure formed in the jawbone implant part and a convex structure formed in the mucosa penetrating part, and the concave-convex joint part is a rotation preventing structure part and a load-bearing structure against horizontal stress Part
In a state where the concave structure of the implantable portion of the jawbone and the convex structure of the mucosal penetrating portion are connected in an uneven manner, both are fixed by screws,
The mucosa penetrating part and the prosthetic support part are fixed with screws,
The mucosa penetrating portion has a rotational torque receiving portion, and the rotational torque generated when the screw is tightened or loosened is received by fixing the rotational torque receiving portion. As a result, the embedded intra-maxillary implant portion An artificial tooth root characterized in that no rotational torque is applied . In the anti-rotation structure part of the concave-convex joint part, the concave structure of the intramaxillary implant part and the convex structure of the mucosal penetration part are each formed in a polygonal shape having a cross section of three or more corners to prevent rotation. And
In the load bearing structure portion of the uneven joint portion, the concave structure of the intramaxillary implant portion and the convex structure of the mucosa penetrating portion are each formed in a circular shape so as to withstand horizontal stress. The artificial tooth root according to claim 1.   The artificial tooth root according to claim 1 or 2, wherein two or more grooves or one or more plate-like protrusions are formed on a side surface of the implantable portion of the jawbone toward the tip thereof. . The artificial tooth root according to any one of claims 1 to 3, wherein the screw for fixing the concave-convex joint portion is doubly fixed by a screw for fixing the prosthesis support portion to the mucosal penetrating portion. .   The artificial tooth root according to any one of claims 1 to 4, wherein the prosthesis support part is fixed to the mucosal penetrating part by another screw.   The artificial tooth root according to any one of claims 1 to 3, wherein fixing to the jawbone implant part, mucosal penetration part, and prosthesis support part is performed by one common screw.   The artificial tooth root according to any one of claims 1 to 6, wherein the intra-mandibular implant part, the mucosal penetration part and the prosthesis support part are made of titanium or a titanium alloy.   The said jawbone implantation part is titanium or a titanium alloy, and the surface of the side surface has a discharge trace or a calcium phosphate ceramic coating with an average roughness of 5 μm or more. Artificial tooth root. The artificial tooth root according to any one of claims 1 to 8, wherein a rotational torque receiving portion of the mucosal penetrating portion is formed on a side surface of the mucosal penetrating portion .

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