JP5385777B2 - Orthodontic implant anchor and orthodontic appliance - Google Patents

Description

  The present invention relates to an orthodontic implant anchor (hereinafter sometimes simply referred to as an implant anchor) for fixing orthodontic appliances and parts for correcting dentition.

  Orthodontic treatment is performed for natural malocclusion of teeth, malocclusion due to tooth damage, or malocclusion due to the influence of temporomandibular joint deformation and the like. In recent years, it has become widespread as an effective treatment for preventive medicine and sports medicine. In addition, many patients desire orthodontic treatment for beauty, and the need for orthodontics tends to increase year by year.

  The most typical orthodontic method is to fix an orthodontic bracket to the tooth surface, and to connect parts that apply stress to move the tooth, such as wires, springs, rubber, plastic rings, etc. It is a method to correct by moving little by little properly.

  In addition to this, a large-scale method for operating the temporomandibular joint and a minor method such as a mouthpiece are performed, and an appropriate method is taken depending on the situation of the patient to be treated.

  Among them, after being fixed together with orthodontic bracket treatment, or after implanting and fixing a screw-shaped implant anchor in the patient's mouth, for example, the upper jaw, the alveolar bone between the teeth, and the root of the teeth The number of cases where correction is performed by the method of applying the moving force is increasing.

  Various implant anchors used for such applications are known. For example, Patent Documents 1 and 2 disclose an implant anchor having a screw shape and embedded in an alveolar bone or the like. Patent Document 1 discloses an implant anchor mainly made of titanium and having an advantageous shape for fixing a wire or the like to the head. Patent Document 2 directly implants bone without drilling it in advance. An upright implant anchor is disclosed. A typical one of such conventional implant anchors has a structure as shown in FIG. An implant anchor 100 shown in FIG. 1 includes a screw portion 101 that is embedded in a gum of a gum or palate, and a head portion 105 that is exposed to the outside and coupled to a biasing means. The head 105 may be provided with a through hole, a groove or the like for coupling to the urging means. In addition, a case in which the head 105 is composed of a plurality of parts and has a complicated shape has been studied.

  On the other hand, a screw portion having a relatively simple shape is generally used. In some cases, such as adjusting the height of the thread 107 or adjusting the height and shape of the screw thread 107 to a taper shape, a single thread having a simple spiral structure as shown in FIG. It has become.

  In general, implant anchors are effective for the treatment of moving teeth inward or outward, moving back and forth, and moving vertically in the correction of extremely deformed dentitions. In order to install in the oral cavity, there are cases where a spare hole is provided in advance using a tool such as a drill or a reamer, and that a screw is directly screwed. In order to firmly fix the implant anchor, structural ingenuity has been repeated, but conventionally, as shown in FIG. It is mainly studied to adopt such a tapered shape, adjust the angle of the thread 107, the screw pitch, the length of the screw, the protruding tip of the tip, and adjust the height and shape. It was.

  Conventionally, titanium or a titanium alloy as described in Patent Document 1 is generally used as a material for an implant anchor. Such a metal material is advantageous in strength, ease of manufacture, cost, and the like. On the other hand, it may be preferable to avoid metal materials from the viewpoint of toxicity. Therefore, the use of nonmetals as an implant material has also been studied. For example, the use of zirconia as an implant material for artificial roots has also been studied (Patent Document 3).

Japanese Patent Application Laid-Open No. 2004-057729 JP 2006-514840 A JP 61-146757 A

  However, due to the fact that orthodontic treatment is carried out over a relatively long period of time and the force is also applied to the implant anchor due to the reaction of the moving force applied to the teeth by the biasing means, the implant anchor loosens or falls off. There was something to do. The loosening of the implant anchors should be avoided as much as possible because not only the orthodontic treatment becomes insufficient, but also bleeding from the implant attachment site and suppuration of the attachment site occur. For this reason, there has been a demand for an implant anchor and an orthodontic appliance that do not easily fall off when attached to the oral cavity.

  An orthodontic implant anchor according to the present invention is for fixing a biasing member for correcting the position of a tooth by applying a moving force to the tooth, and in order from the distal end to the distal end, a screw part, The first fitting portion, the intermediate portion, the second fitting portion, and the head portion, each of the two fitting portions has an outer diameter at the distal end side than an outer diameter at the distal end portion. The frustoconical shape is a small frustoconical shape, and the intermediate portion is defined by a distal end end section of the first fitting portion and a distal end end section of the second fitting portion. It is comprised by these.

  Further, an orthodontic appliance according to the present invention is for correcting a position of a tooth by applying a moving force to the tooth, a bracket to be fixed to the tooth, and a biasing member for applying the moving force to the tooth. An implant anchor coupled to the biasing member for fixing the biasing member in the oral cavity, the implant anchor in order from the distal end to the distal end, in order, a screw portion and a first fitting Each of the two fitting portions has a truncated cone shape in which the outer diameter of the distal end portion is smaller than the outer diameter of the distal end portion, respectively. The intermediate portion is configured in a frustoconical space defined by the end-side end section of the first fitting portion and the tip-side end section of the second fitting portion. It is characterized by being.

  According to the present invention, there is provided an orthodontic implant anchor that is prevented from loosening or falling off when attached to the oral cavity. Furthermore, when this implant anchor is formed of ceramics, it can be made simpler with higher dimensional accuracy and higher quality than an implant anchor that is currently made by metal processing. Furthermore, it is possible to obtain an implant anchor that is safer, safer, and less expensive than general implant anchors, has high biocompatibility, and has little biological damage.

The side view of the conventional orthodontic implant anchor. 1 is a side view of an orthodontic implant anchor according to an embodiment of the present invention. FIG. The conceptual sectional drawing of the part by which the implant anchor by this invention was attached in the oral cavity. The side view of the intermediate part of the implant anchor by this invention. FIG. 6 is a side view of an orthodontic implant anchor according to another embodiment of the present invention. FIG. 6 is a side view of an orthodontic implant anchor according to yet another embodiment of the present invention. FIG. 6 is a side view of an orthodontic implant anchor according to yet another embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the name of each part of a screw part or a screw structure shall comply with JIS standards (for example, JIS B 0101 screw term) in principle.

  In general, the orthodontic implant anchor is preferably attached in the vicinity of the tooth to be corrected. In particular, it is ideal to attach to the portion of the alveolar bone between the root and the root so as not to damage the root. In order to attach to such a position, the attachment position is usually determined at an appropriate part of the alveolar bone, the meat of that part is incised as necessary, and a small diameter drill is used at an appropriate attachment position that does not damage the tooth root. Drill and screw the implant anchor into the hole. At this time, a portion having a screw structure that can be screwed into the alveolar bone is a screw portion at the tip. In the case of a conventional implant anchor, the screw portion 101 in FIG. 1 is embedded in the alveolar bone and meat on the surface thereof.

  On the other hand, the portion that remains exposed outside the bone is the head 105. A part of the head, for example, the sleeve 106 in FIG. 1, may be covered with meat around the part, but here “exposed to outside” means exposed to the outside of the bone. Even if it is covered with meat, the part is the “head exposed to the outside”.

  On the other hand, the implant anchor according to the present invention has a special structure between the screw portion and the head. One embodiment of such an implant anchor according to the present invention is shown in FIG. The implant anchor shown in FIG. 2 includes a screw part 201, a first fitting part 202, an intermediate part 203, a second fitting part 204, and a head part 205 in that order from the distal end to the distal end.

  In the present invention, the head of the implant anchor exhibits the same function as a conventional implant anchor. For example, the implant anchor 200 shown in FIG. The head 205 includes a terminal portion 207 having a hexagonal cross section. The head is connected to biasing means such as a spring, rubber, or wire that bridges the teeth to be corrected and applies a moving force to the teeth. For this reason, a through hole or a groove useful for the connection may be formed, but any shape may be used, and a conventionally known one may be employed. Also, the distal end 207 of the head can have an advantageous shape for applying a rotational force when screwing the implant anchor. For example, the end of the head may be hexagonal, or a +,-, or hexagonal groove may be formed on the end surface. Furthermore, it is good also as shapes, such as a round head, a round flat head, and a bind head. The size of the head of the implant anchor according to the present invention can be the same as that of a conventional implant anchor. The length of the head, that is, the length of the exposed portion of the implant anchor can be appropriately set as long as it is long enough to fix the wire or the like. In addition, a sleeve or the like can be provided on the head, a multi-purpose member with other functions added, or a multi-purpose account with the function of the head itself can be added.

  An implant anchor 200 shown in FIG. 2 includes a screw portion 201 having a screw structure. The screw portion 201 corresponds to a screw portion in a conventional implant anchor. That is, it has the function of converting the rotational force applied to the head 207 into the propulsive force of the implant anchor and implanting the implant anchor in the alveolar bone.

  The length of the screw portion 201 of the implant anchor according to the present invention is not particularly limited, but can be shorter than the conventional one in terms of structural safety and reliability. Specifically, it is generally 3 to 18 mm, preferably 4 to 14 mm. This length is selected in consideration of the structure such as the bone of the portion to which the implant anchor is attached, the force applied by the biasing means, and the like. The structure of the screw portion is generally a single thread, but may be a multiple thread.

  The threaded portion 201 of the implant anchor in FIG. 2 has a tapered shape whose tip side is thinner than the terminal side. Such a structure is preferred because it tends to improve the stability of the implant anchor after attachment, but it need not necessarily be tapered.

  Moreover, the implant anchor by this invention comprises the two fitting parts. When these two fitting parts are embedded in the alveolar bone, they each have a function of fitting into the alveolar bone and stabilizing the position of the implant anchor. The alveolar bone is a bone that connects the bone part of the jaw bone and the tooth, and this bone has a groove-like or pocket-like structure, and the teeth are fixed so that the teeth can be fitted into the pocket. .

  Here, a cross-sectional view in the direction perpendicular to the tooth arrangement direction between adjacent teeth is as shown in FIG. Here, the tooth 301 illustrated by a dotted line is positioned in front of and behind the illustrated cross section. The tooth 301 is fixed to the alveolar bone 302, and a periodontal membrane 303 exists between the tooth 301 and the alveolar bone 302. The outer surface of the alveolar bone is covered with gingiva 304.

  And the implant anchor 200 by this invention is fixed to an alveolar bone, for example, as shown in FIG. That is, for example, when the right side of FIG. 3 is the outside of the jawbone, the first fitting portion 202 is fitted to the inner portion of the alveolar bone, and the second fitting portion is fitted to the outer portion of the alveolar bone. Here, each fitting portion has a truncated cone shape in which the outer diameter of the distal end portion is smaller than the outer diameter of the distal end portion. Therefore, when the implant anchor is screwed in, the alveolar bone It will fit tightly. For this reason, since the implant anchor according to the present invention is fitted to the alveolar bone at two locations, the distal end side and the distal end side, the position is stable and it is difficult to fall off.

  Each of the two fitting portions has a truncated cone shape in which the outer diameter of the distal end portion is smaller than the outer diameter of the distal end portion. Here, the second fitting portion is preferably thicker than the first fitting portion. Since the second fitting part is fitted to the alveolar bone after the first fitting part has penetrated, the stress between the alveolar bone and the second fitting part is smaller than the first fitting part. This is because it becomes smaller and the frictional force becomes smaller and the stability of the implant anchor may be lowered. Therefore, specifically, it is preferable that the outer diameter of the end side end of the first fitting portion is equal to or smaller than the outer diameter of the end end of the second fitting portion. Moreover, it is also preferable that the extension of the side surface of the first fitting portion coincides with the side surface of the second fitting portion. Such a structure corresponds to a structure in which an intermediate part and a screw part are formed by cutting from a conical structure. That is, it is advantageous when the structure of the present invention is formed from a conical structure by machining. Moreover, even if it is not the case of manufacturing by machining, it is preferable because the effects of the present invention can be obtained while being structurally relatively simple.

  Moreover, each fitting part does not need to be a perfect truncated cone shape. For example, the ridge line portion of the truncated cone may be chamfered. Moreover, in the cross-sectional view of the plane passing through the central axis of the implant anchor, the side corresponding to the side surface may be configured by a curve. In other words, the diameter of the fitting portion most typically increases at a constant rate toward the distal end or the distal end. However, the diameter of the fitting portion may increase discontinuously from the front end side toward the end side, or may decrease in a certain portion. What is important is that a portion of the distal end side is thicker than the end portion on the distal end side.

  In the first and second fitting portions, the inclination angle of the side surface is not particularly limited. Here, the inclination angle of the side surface is an angle formed by the axis of the implant anchor and the side surface of the fitting portion. When this inclination angle is small, the load when implanting an implant anchor tends to be small. On the other hand, when the inclination angle is increased, the pressure when fitted is apt to increase. However, when the inclination angle is excessively increased, the pressure decreases, and it becomes easy to drop off or cannot be embedded by screwing. For this reason, it is preferable that the inclination angle is appropriately selected. Specifically, the inclination angle is generally 0.1 to 20 °, preferably 0.3 to 15 °.

  The longer the length of the first and second fitting portions, the more the stability after attachment tends to increase. However, as is clear from FIG. 3, even if the thickness of the alveolar bone is made longer, the effect of improving the stability does not increase. That is, the optimum length of the fitting portion varies depending on the size of the alveolar bone to be implanted. Specifically, the length of each fitting portion is preferably 0.5 to 4.0 mm, and more preferably 0.8 to 3.0 mm.

  Moreover, it is preferable that the diameter of the front end side end part of a 1st fitting part has an outer diameter larger than the diameter of the trough of the external thread of a thread part. The diameter of the male thread valley is the diameter of the cylinder formed at the bottom of the groove of the male thread. If the diameter of the tip end of the first fitting part is smaller than this, the first fitting part will not be able to contact the bone etc. sufficiently when the implant anchor is screwed in, and the frictional force will not be generated sufficiently. is there. If the entire threaded portion is tapered, the thread diameter of the threaded portion of the threaded portion is the portion of the threaded portion that is adjacent to the end of the first fitting portion. And

  As described above, the implant anchor according to the present invention has a fitting portion, thereby increasing the contact resistance area between the alveolar bone to be implanted, particularly ideally, the alveolar bone between the roots, and fitting. It is considered that the implant anchor is prevented from falling off when the portion is strongly fitted to the alveolar bone. Such an effect cannot be obtained with a conventional implant anchor as shown in FIG. The conventional implant anchor has a uniform taper from the tip to the end. For this reason, if a force is applied to the head, a moment is applied to the tip and it may be loosened. Therefore, in the implant anchor according to the present invention, in order to prevent the looseness recognized in such a conventional implant anchor and to obtain the effect of preventing the dropout, the outer diameter of the tip end portion of the first fitting portion is a screw. It is preferable that it is larger than the maximum value of the diameter of the valley of the male screw. Furthermore, it is preferable that the outer diameter of the terminal side end part of a 1st fitting part is below the outer diameter of the front end side terminal of a 2nd fitting part. By setting it as such a structure, a 2nd fitting part can be stuck more closely to an alveolar bone.

  The implant anchor according to the present invention is attached by being screwed into the alveolar bone with or without a pilot hole in the alveolar bone as required. At this time, it is also preferable to make the outer diameter of the first fitting portion larger than the outer diameter of the screw portion. The outer diameter of the threaded portion is the diameter of a cylinder formed at the top of the male thread crest. In addition, when the whole thread part is a taper shape, the outer diameter of a thread part shall be in the part which the front end side of a 1st fitting part adjoins among thread parts. By setting it as such a shape, since the pressure concerning the surface of a 1st fitting part can be enlarged and a frictional force can be enlarged, the fall of an implant anchor can be prevented. Therefore, the outer diameter of the first fitting portion is preferably 100% or more of the outer diameter of the screw portion, and more preferably 105% or more. On the other hand, if the outer diameter of the end portion on the front end side of the first fitting portion is excessively large with respect to the outer diameter of the screw portion, the flat ground portion cannot be screwed or screwed by the screw portion becomes impossible. For this reason, it is preferable that the outer diameter of the front end side end part of a 1st fitting part is 100% or less of the outer diameter of a screw part, and it is more preferable that it is 95%.

  The side surfaces of the two fitting portions are preferably smooth from the viewpoint of ease of manufacturing. In order to exert the frictional force by such a fitting part more strongly, the surface shape of the fitting part can also be adjusted. For example, it is preferable to form a groove regularly or irregularly on the side surface of the fitting portion. Thus, by forming a groove on the side surface of the fitting portion, it is possible to increase the frictional force between the alveolar bone and the fitting portion, and to make it more difficult to fall off. Such a groove may be formed only in one of the fitting portions or in both of the fitting portions.

  The direction in which the grooves are formed is not particularly limited, and may be parallel to, perpendicular to, or oblique to the axial direction of the implant anchor. A combination of these may also be used. Such a groove can be formed on the side surface of the fitting portion as a so-called knurling process. For example, knurl processing such as iris knurl, vertical knurl, spiral knurl can be performed.

  And the implant anchor by this invention has the intermediate part 203 between two fitting parts. The intermediate portion 203 is a portion that comes into contact with relatively soft tissue between the inner and outer alveolar bones when implanted in the oral cavity. This intermediate portion is a frustoconical space defined by a distal end end section of the first fitting portion and a distal end end section of the second fitting portion, as indicated by a broken line A in FIG. It is configured. That is, it can also be said that the intermediate portion is a portion that is narrowed between the first and second fitting portions. Since the intermediate portion is thus narrow, the living tissue between the alveolar bones is compatible with the intermediate portion, and in some cases, the implant anchor is more difficult to fall off when it is fused. In addition, the distal end portion of the first fitting portion is caught in the biological tissue that is compatible with the intermediate portion, and the implant anchor is difficult to drop off. The intermediate portion may have a straight shape in which the outer diameter of the joint portion with the distal end side of the first fitting portion and the outer diameter of the joint portion with the distal end side end portion of the second fitting portion are the same diameter, The taper shape may be such that the outer diameter of the joint portion with the distal end side end portion of the second fitting portion is larger than the outer diameter of the joint portion with the distal end side of the one fitting portion.

  In order to increase the affinity of the intermediate portion 203 to the living tissue, the surface of the intermediate portion can be processed. That is, by forming grooves or holes regularly or irregularly on the surface of the intermediate portion, it is possible to easily bind biological tissues. As an example, as shown in FIG. 5, for example, a screw structure 208 having the same pitch as that of the tip screw portion 201 can be formed on the surface of the intermediate portion 203. However, unlike the screw structure of the distal end portion 201, the screw structure formed in the intermediate portion 203 is not for obtaining a propulsive force when implanting an implant anchor. Therefore, it is not necessary to have the same structure as the screw portion at the tip, and for example, as shown in FIG. 6, the pitch, lead angle, screw thread height, and the like may be different. Furthermore, it is also possible to use a reverse screw as shown in FIG. Further, although not shown, a ring-shaped groove can be formed on the surface of the intermediate portion, or knurling can be performed. Moreover, a through-hole can be provided or a dent can be provided. In addition, the implant anchor shown in FIG.

  Here, the surface processing such as the grooves provided in the intermediate portion 203 is for increasing the affinity to the living tissue, and the purpose is different from the surface processing in the fitting portion described above. For this reason, it is common for the groove provided in the intermediate part to have a larger groove width and depth than the groove provided in the fitting part.

  In addition, the size of the implant anchor according to the present invention is not particularly limited, and can be appropriately adjusted according to the type of animal to be applied. For example, when applied to a human, the length from the tip to the end is generally 3 to 18 mm, preferably 4 to 14 mm. The thickness of the thickest portion embedded in the alveolar bone, that is, the maximum diameter of the second fitting portion is generally 0.5 to 5 mm, preferably 0.8 to 3 mm.

  The implant anchor according to the present invention has a great feature in its shape, and the material used for manufacturing is not limited. Therefore, any material can be used.

  Preferred materials used in the manufacture of the implant anchor according to the present invention include ceramics or metals. Among these, it is more preferable to use ceramics as the material of the implant anchor according to the present invention. This is due to the following reason. First, ceramics have a higher biocompatibility than metal materials, so that rejection is unlikely to occur during implantation. In addition, even when it comes into contact with a living tissue, a wound current is not generated unlike a metal material, so that it is difficult to cause damage to the living body. For this reason, even when attaching to a living body by screwing into a bone, the living tissue is not unnecessarily damaged. Moreover, since it is a nonconductor, it is harmless even if it is damaged in a living tissue and cannot be removed and remains in the living body. Furthermore, even if attached in the oral cavity, it does not produce a metallic taste. Thus, ceramics are a preferred material for implant anchors.

  Examples of ceramics that can be used in the implant anchor according to the present invention include various metal oxides, silicides, nitrides, fluorides, borides, and the like. Any of these may be used, but an oxide is generally preferable, and zirconium oxide is particularly preferable. However, partially stabilized zirconia with further improved strength and toughness, in which at least one of yttrium oxide, aluminum oxide, cerium oxide, or hafnium oxide, particularly yttrium oxide, is added to zirconium oxide is most preferable.

  Moreover, as a material for a general dental implant, pure titanium or a titanium alloy is often used, but these can also be used in the present invention. The reason why these metals are generally used as dental implant materials is that they are non-rusting, have a low elastic modulus, have high mechanical strength, and have good biocompatibility among metals. However, it is known that when a metal material comes into contact with a living tissue, an injury current is generated, and most of the contacted cells are damaged. From this point of view, it is preferable to use the above-mentioned ceramic that does not generate a wound current as a material, rather than using a metal material.

  However, metal materials are relatively easy to obtain, and the cost of the materials themselves is relatively low. Moreover, since it is excellent in tension resistance, there is also an advantage that it is difficult to break. From this point of view, a metal, particularly a titanium alloy having excellent biocompatibility can also be used.

  In addition, the implant anchor according to the present invention may be one in which the surface of a molded body made of a hard material such as metal is coated with the above-described ceramic material. Since an electric current may be generated and the peeled ceramic material may remain in the body of the living body, it is preferable that the entire implant anchor is made of ceramic.

  Although the manufacturing method of the implant anchor by this invention is not specifically limited, For example, extrusion molding, injection molding, press molding, etc. can be utilized. Moreover, it is also possible to manufacture by machining such as cutting and shaving.

  Here, the implant anchor according to the present invention has a complicated shape. For this reason, it is preferable to manufacture by using ceramics as a material, molding the powder, and further firing it. In particular, it can be easily and inexpensively manufactured by a ceramic injection mold (hereinafter referred to as CIM method).

  Here, the ceramic injection mold (CIM) is the same technology as the plastic injection mold (injection molding). The ceramic powder is kneaded into a binder, injection molded into a mold, and then fired. Then, the binder is removed to obtain a ceramic sintered body. Compared to metal injection molding (MIM molding), in which metal is kneaded into a binder and injection molding is performed in the same way, CIM molding is easy to incorporate fine particle powder and has good moldability. There is a tendency to obtain a knot.

  Further, according to the CIM method, the smoothness of the surface of the manufactured implant anchor is increased, so that the load is reduced when it is attached to a living body. In addition, it is possible to manufacture with low cost and high accuracy compared to machining, and there is an advantage that burr-like protrusions and the like that easily damage a living tissue are not easily formed.

  On the other hand, when an implant anchor is to be manufactured from a metal material, it is generally manufactured by machining. However, since the implant anchor according to the present invention has a complicated shape, it is relatively difficult to manufacture by mechanical processing, and the manufacturing cost tends to increase due to the complexity. Further, when a metal material such as titanium is machined and formed, burrs are easily generated, and the burrs may cause tissue damage when attached to a living body. From this point of view, it is preferable to use the ceramics as a material. In addition, as with the ceramics described above, it is possible to process a metal by injection molding, but generally there is a higher tendency for the forming accuracy to be lower than that of CIM, and the possibility of an increase in secondary processing costs is increased. . Therefore, it is disadvantageous to process the metal material with an injection mold. For this reason, it is preferable to manufacture by a CIM method using ceramics as a material.

  The implant anchor according to the present invention can be combined with any orthodontic appliance known in the art. In other words, any conventionally known orthodontic appliance implant anchor can be replaced by an implant anchor according to the present invention. Such an orthodontic appliance includes a bracket that is fixed to a tooth to be corrected, a biasing member that is coupled to the bracket and applies a moving force to the tooth, and the above-described implant anchor that is coupled to the biasing member. It comprises. Such orthodontic appliances do not loosen or fall off when fixed in the oral cavity, and enable sufficient orthodontic treatment.

Example 1
100 parts of water is added to 80 parts of β-tricalcium phosphate as a main material and 20 parts of polyvinyl alcohol as a binder. After kneading, CIM is formed into a shape as shown in FIG. 2, and this material is placed in an oxygen atmosphere. Baked. As a result, an orthodontic implant anchor made of β-tricalcium phosphate and having a length excluding the head 205 (201 + 202 + 203 + 204) of 6.0 mm and a length of the head 205 of 2.0 mm was obtained.
The size of each part was as follows. The front end side diameter of the first fitting portion 202 was 1.2 mm, and the end side diameter was 1.3 mm. The intermediate portion 203 has a tapered shape, the outer diameter of the joint portion with the distal end side of the first fitting portion is 1.1 mm, and the outer diameter of the joint portion with the tip end portion of the second fitting portion is 1. 3 mm. Furthermore, as for the 2nd fitting part 204, the front end side diameter was 1.4 mm and the terminal side diameter was 1.6 mm.
Further, the screw part 201 on the tip side is formed with a screw having a screw pitch of 0.25 mm, and the tip is rounded.

The orthodontic implant anchor according to the present invention is, for example, incised in a portion of the alveolar bone in the vicinity of the tooth to be corrected, if necessary, and drilled with a small diameter drill. As shown in FIG. 3, it is attached by screwing an orthodontic implant anchor. At this time, the attachment position should be selected appropriately so as not to damage the tooth root.
At that time, since the orthodontic implant anchor of Example 1 has the structure specified in the present invention, it can be firmly fixed as shown in FIG. Since it is formed of ceramics, it is safe, secure and inexpensive, has high biocompatibility, and has little biological damage.

Example 2
The orthodontic implant anchor of Example 1 was manufactured by changing a part of the shape. Specifically, as shown in FIG. 5, a screw having a screw pitch of 0.25 mm is formed on the surface of the taper-shaped intermediate portion, and a sleeve 206 is further provided. An orthodontic implant anchor was obtained.

Example 3
The orthodontic implant anchor of Example 1 was manufactured by changing a part of the shape. Specifically, as shown in FIG. 6, a screw having a screw pitch of 0.25 mm is formed on the surface of the tapered intermediate portion, and the screw pitch of the screw portion 201 on the tip side is changed to 0.5 mm. An orthodontic implant anchor of Example 3 was obtained in the same manner as Example 1.

Example 4
The orthodontic implant anchor of Example 1 was manufactured by changing the shape of the intermediate part. Specifically, as shown in FIG. 7, the same structure as that of Example 1 was adopted except that a screw structure with a screw pitch of 0.25 mm between the screw portion on the tip side and the reverse screw was formed on the surface of the tapered intermediate portion 203. Thus, an orthodontic implant anchor of Example 4 was obtained.

Examples 5-8
In Examples 1 to 4, orthodontic implant anchors of Examples 5 to 8 were obtained in the same manner as in Examples 1 to 4 except that the surfaces of the first fitting part and the second fitting part were knurled. It was.

Examples 2 to 8 were mounted in the oral cavity in the same manner as in Example 1, but each example was firmly fitted as shown in FIG. 3 to prevent loosening and falling off, and this was formed of ceramics. The implant anchor is an implant anchor that is safe, secure, inexpensive, has high biocompatibility, and has little biological damage.
In particular, since the screw of the second embodiment is formed with a screw at the intermediate portion as a surface processing of a groove or the like, it has a higher affinity for living tissue than the other and has a sleeve. The positioning was excellent, and it also had an anti-swaying effect.
In Example 3, since the screw pitch on the tip side is widened, there is a difference in the effect of retaining, and it is difficult to cause chipping of the ceramic material by changing the lead angle and reducing the edge of the screw thread. there were.
Moreover, since Example 4 was a reverse screw, the retaining effect which assists fitting force was high.
Further, each of Examples 5 to 8 was slightly superior in retaining effect and biocompatibility to the corresponding Examples 1 to 4 due to the effect of knurling.

Comparative Example 1
Titanium metal was used as a material and cut into a shape as shown in FIG. 1 to form an orthodontic implant anchor having a total length of 8 mm.
The screw pitch of the screw portion 101 was 0.5 mm, and the tip was sharp and sharp.

Comparative Example 1 was attached to the oral cavity at the same position as in Example 1, but at that time, a threaded portion continuous with a sharp tip without using a method of drilling in that position in advance with a small diameter drill and screwing the implant anchor The implant anchor itself of Comparative Example 1 having the above was fixed by a general screwing method for screwing.
The implant anchor of Comparative Example 1 does not have a retaining part and does not have an intermediate part as compared with the above example, so that it reversely rotates during use due to a tensile stress of a wire, a biological rejection reaction, or the like. Therefore, there was a risk of loosening or falling off.
In addition, since the material is titanium metal, biological damage due to injury current occurs at the time of wearing, and the subsequent biocompatibility is poor.

100, 200 Implant anchor 101, 201 Screw part 105, 205 Head part 106, 206 Sleeve 107, 208 Thread 202 First fitting part 203 Intermediate part 204 Second fitting part 301 Teeth 302 Alveolar bone 303 Periodontal ligament 304 Gingiva

Claims (8)

  An orthodontic implant anchor for fixing a biasing member for applying a moving force to a tooth to correct the position of the tooth, in order from the distal end to the distal end, a screw part, a first fitting part, An intermediate part, a second fitting part, and a head part, each of the two fitting parts being in the shape of a truncated cone having an outer diameter at the distal end side smaller than an outer diameter at the distal end part. And the intermediate portion is configured in a truncated cone-shaped space defined by a distal end side cross section of the first fitting portion and a distal end side cross section of the second fitting portion. An orthodontic implant anchor.   The orthodontic implant anchor according to claim 1, wherein an outer diameter of a distal end portion of the first fitting portion is equal to or smaller than an outer diameter of a distal end end of the second fitting portion among the fitting portions.   The orthodontic implant anchor according to claim 1 or 2, wherein grooves or holes are regularly or irregularly formed on the surface of the intermediate portion.   The orthodontic implant anchor according to any one of claims 1 to 3, wherein a groove is regularly or irregularly formed on at least one side surface of the fitting portion.   The orthodontic implant anchor according to any one of claims 1 to 4, wherein the orthodontic implant anchor is made of ceramics.   The orthodontic implant anchor according to claim 5, wherein the ceramic is yttria-added partially stabilized zirconia.   The orthodontic implant anchor according to claim 5 or 6, which is formed by a ceramic injection molding method.   An orthodontic appliance for applying a moving force to a tooth to correct the position of the tooth, a bracket fixed to the tooth, a biasing member coupled to the bracket and applying a moving force to the tooth, An implant anchor coupled to the urging member for fixing the urging member in the oral cavity, the implant anchor in order from the distal end to the distal end, in order, a screw portion and a first fitting portion Each of the two fitting portions has a truncated cone shape in which the outer diameter of the distal end portion is smaller than the outer diameter of the distal end portion. The intermediate portion is configured in a frustoconical space defined by a distal end end section of the first fitting portion and a distal end end section of the second fitting portion. Orthodontic appliances characterized by being.

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