KR20150068555A - Fixture - Google Patents

Abstract

The present invention relates to a fixture, comprising: a first shaft having a first screw thread formed on an outer peripheral surface; and a second shaft having a second screw thread which is extended downward to a lower end of the first shaft and which has a greater pitch than the pitch of the first screw thread, and having a plurality of cutting edges formed at regular intervals in a circumferential direction at a lower end to allow a self-tapping when being implanted to an alveolar bone. The fixture of the present invention forms a female screw thread on an inner circumferential surface of a groove for being inserted with a bone tissue by the cutting edges provided in a lower side of the second shaft, thus improving a work efficiency. The invention has the advantage of improving a fixing force of the bone tissue as a part of the bone tissue is drawn into the cutting edges during osseointegration.

Description

Fixture {Fixture}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixture, and more particularly, to a screw type fixture for implantation into an alveolar bone.

In general, a dental implant includes a fixture (= a substructure) to be placed on the alveolar bone, an abutment to be connected to the fixture, and an actual artificial crown mounted on the abutment, .

More specifically, the fixture has a threaded portion formed on an outer surface thereof, and a screw hole for connecting an abutment having a predetermined depth passing through the screw hole is formed on an upper surface of the fixture. Before tightening the abutment, tighten the cover screw to the screw hole for connecting the abutment to close the butt.

The most important point of the dental implant having such a configuration is that strong fixation of the fixture to the alveolar bone should be made so as to cope with repetitive load generated during chewing of the food. For this purpose, This should happen effectively.

Here, the implant treatment method will be briefly described as follows.

When the fixture is placed on the alveolar bone, the gingival bone is exposed to the alveolar bone by flap technique, which is widely used to remove the flap composed of the gingival tissue together with the periosteum, and the screw part of the fixture is placed in the alveolar bone, After the cover screw is fastened to the top of the fixture, the flap is closed and the first operation is completed.

At this time, while the cover screw is waiting for the fixture to be attached to the alveolar bone, the bacteria and foreign matter remaining in the oral cavity are prevented from entering the inside of the fixture, that is, into the screw hole for connecting the abutment, It concludes and closes.

After the fixture and cover screw are applied, the fixation period of the fixture usually takes 3-6 months.

Next, the gingiva is opened to remove the cover screw, the abutment is fastened to the screw hole formed in the upper part of the fixture, and an artificial crown serving as an actual tooth is mounted thereon. Is completed.

However, a general fixture rotates a plurality of times to the bone tissue to form a female thread in the bone tissue. In this case, the bone tissue is firm and the operation for placing is not easy. Even if the bone is attached after the implantation, There is a disadvantage in that it is detached from the bone tissue or deteriorates in binding force by reversely rotating in the opposite direction with respect to the mounting direction.

Korean Patent Registration No. 10-0817209: Dental Implant Fixture

It is an object of the present invention to provide a fixture having a plurality of cutting edges for forming a female thread on an inner circumferential surface of a groove for insertion of a bone tissue to guide the insertion of the bone tissue.

According to an aspect of the present invention, there is provided a fixture including a first shaft portion having a first screw thread formed on an outer circumferential surface thereof, a second shaft portion extending downwardly from a lower end portion of the first shaft portion, And a second shaft portion having a plurality of cutting edges spaced apart from each other along a circumferential direction at a lower end portion to be self-tapping when the alveolar bone is inserted into the alveolar bone.

The cutting edges are drawn into a predetermined depth from an outer circumferential surface of the second shaft portion, extend along the longitudinal direction of the second shaft portion, and are radially arranged with respect to the center of the second shaft portion.

Wherein the cutting edge has a first incision surface extending in the radial direction of the second shaft portion and a second incision surface in the rotation direction in which the second axis portion is placed in the alveolar bone at an end portion of the first incision surface adjacent to the center of the second axis portion And a second incision surface orthogonal to the first incision surface is provided.

The first and second shaft portions may be formed along a boundary line between the first and second shaft portions so as to reduce a load caused by a difference in shape from the second screw thread when the first screw thread is inserted into the alveolar bone. A plurality of cutting grooves may be formed to be spaced apart from each other.

The cutout groove may be formed to extend in a predetermined depth from an outer circumferential surface of the first and second shaft portions and extend in the vertical direction so that the upper and lower ends thereof are respectively located at the first and second shaft portions.

The cutting grooves are radially arranged with respect to the center of the first and second shaft portions, and each of the cutting grooves is formed at a position facing the space between adjacent cutting edges.

Wherein the incision groove has a third incision surface extending in parallel with a radial direction of the first axis portion and an end portion of the first incision surface adjacent to the center of the first axis portion so that the first axis portion is placed in the alveolar bone And a fourth incision surface extending in a direction opposite to the rotation direction and recessed toward the center of the first axis portion.

At this time, the ridge of the first screw thread at the uppermost end is tapered at a predetermined inclination angle with respect to an imaginary extension line extending upwardly of the ridge of the first screw thread at the lower adjacent position.

At this time, the ridge of the first screw thread at the uppermost end is inclined so that the upper end thereof is farther from the center of the first shaft than the lower end thereof, and the inclination angle is preferably 6 ° to 12 °.

The fixture according to the present invention has a plurality of cutting edges provided at the lower end of the second shaft portion to form a female thread on the inner circumferential surface of the groove for insertion of the bone tissue to guide the fixture to be placed and improve work efficiency, Is inserted into the cutting edge to improve the fixation force on the bone tissue.

1 is a perspective view of a fixture according to an embodiment of the present invention,
Figure 2 is a side view of the fixture of Figure 1,
FIG. 3 is a rear view of the fixture of FIG. 1,
4 is a perspective view of a fixture according to another embodiment of the present invention,
Figure 5 is a side view of the fixture of Figure 4,
6 is a side view of a fixture according to another embodiment of the present invention.

Hereinafter, a fixture according to a preferred embodiment of the present invention will be described in more detail with reference to the accompanying drawings.

1 to 3 show a fixture 100 according to the present invention.

Referring to the drawings, a fixture 100 is mounted on a bone tissue of a human body and includes a first shaft portion 110 having a first thread 111 formed on an outer circumferential surface of the first shaft portion 110, And a second shaft portion 120 having a plurality of cutting edges 122 spaced apart from each other along the circumferential direction at a lower end portion to self-tap on the alveolar bone to form a second screw thread 121 on the outer circumferential surface.

At this time, the bone tissue consists of cortical bone and cancellous bone. The cancellous bone is relatively soft bone tissue inside the bone, and the cortical bone is harder than the cancellous bone and forms a relatively thin film that generally surrounds the cancellous bone. Therefore, when the fixture is completely placed on the bone tissue, the length of the portion contacting the cancellous bone is larger than the length of the portion contacting the cortical bone.

The first shaft portion 110 is formed in a cylindrical shape extending in the vertical direction, and a first screw thread 111 is formed on the outer circumferential surface. A fastening hole is formed on the upper surface of the first shaft 110 so that an abutment for an implant can be fastened. The first thread 111 is preferably formed of a trapezoidal screw having a first ridge.

The second shaft portion 120 is formed in a cylindrical shape extending downward at a lower end portion of the first shaft portion 110, and a second screw thread 121 is formed on an outer circumferential surface. The second screw thread 121 is formed of a trapezoidal screw having a second ridge and is formed to have a pitch larger than the pitch of the first screw threads 111. [ The second ridgeline of the second screw thread 121 is preferably formed to have a vertical width larger than the vertical width of the first ridges 111 of the first screw thread 111. [

The second shaft portion 120 forms a first female thread corresponding to the second thread 121 on the inner circumferential surface of the insertion port when the first shaft portion 120 is inserted into the insertion hole for inserting the fixture of the bone tissue and then the first shaft portion 110 is inserted into the insertion hole of the bone tissue The second female thread having a pitch smaller than the pitch of the first female thread is formed on the inner circumferential surface of the insertion port at the time of insertion, thereby increasing the fixation force to the bone tissue.

Three cutting edges 122 are formed at the lower end of the second shaft portion 120. The cutting edge is arranged radially with respect to the axis of the second shaft portion 120 and is drawn into the predetermined depth from the outer circumferential surface of the second shaft portion 120 and extends along the longitudinal direction of the second shaft portion 120 by a predetermined length do. In the illustrated example, three cutting edges 122 are formed. However, the cutting edge 122 is not limited to the illustrated example, but four or more cutting edges 122 may be formed.

The cutting edge 122 also includes a first cut surface 123 extending in the radial direction of the second axis 120 and a second cut surface 123 adjacent to the center of the second axis 120, A second incision surface 124 extending in a direction opposite to the rotational direction in which the second shaft portion 120 is inserted into the alveolar bone and orthogonal to the first incision surface 123, have. The cutting edge 122 performs a selp-tapping operation when the second shaft 120 is placed on the bone tissue. That is, when the second shaft portion 120 is inserted into the insertion hole for inserting the fixture of the bone tissue, the cutting edge 122 forms a female thread on the inner circumferential surface of the insertion port, I will lead the installation.

At this time, since the three cutting edges 122 are formed in a radial shape as described above, self tapping is performed in multiple stages when the second shaft portion 120 is placed, so that the second axis portion 120 can be easily placed. In addition, after the second shaft portion 120 is completely inserted, a part of the bone tissue is introduced into the cutting edge 122 when the bone is attached, thereby improving the fixation force on the bone tissue.

4 to 5 show a fixture 200 according to another embodiment of the present invention.

Elements having the same functions as those in the previous drawings are denoted by the same reference numerals.

Referring to the drawings, the first and second shaft portions 110 and 120 of the fixture 200 are configured such that when the first thread 111 is inserted into the alveolar bone, a load generated due to a difference in shape from the second thread 121 A plurality of cutting grooves 210 are formed so as to be spaced apart from each other along a boundary line between the first and second shaft portions 110 and 120.

The cutout groove 210 is extended from the outer circumferential surface of the first and second shaft portions 110 and 120 to a predetermined depth and is formed to extend vertically so that the upper and lower ends thereof are located at the first and second shaft portions 110 and 120, respectively. Therefore, it is preferable that the incision groove 210 is formed to cut a part of the first and second threads 111 and 121.

At this time, three cutting grooves 210 are arranged radially with respect to the center of the first and second shaft portions 110 and 120, and each cutting groove 210 is opposed to a space between adjacent cutting edges 122 As shown in FIG. That is, the cutting grooves 210 are preferably arranged to be positioned between the cutting edges 122.

The incision groove 210 may include a third incision surface 211 extending in parallel to a radial direction of the first shaft portion 110 and a second incision surface 211 extending from the first incision surface 211 adjacent to the center of the first shaft portion 110. [ A fourth incision surface 212 extending in a direction opposite to the rotation direction in which the first shaft portion 110 is inserted into the alveolar bone and recessed toward the center of the first shaft portion 110 is provided at an end of the first shaft portion 123 .

The incision groove 210 performs a self-tapping operation when the first shaft portion 110 is placed on the bone tissue. That is, when the first shaft portion 110 is inserted into the insertion hole for inserting the fixture of the bone tissue, the cutting edge 122 forms a female thread on the inner circumferential surface of the insertion port, I will lead the installation. At this time, since the cutout groove 210 is formed radially with respect to the center of the first shaft portion 110, the tapping operation is performed in multiple stages when the first shaft portion 110 rotates. Since the cutting grooves 210 are arranged between the cutting edges 122, a tapping operation by the cutting groove 210 and a cutting operation by the cutting edge 122 are performed during the positioning of the first and second shaft portions 110 and 120 It is prevented from being excessively applied to the bone tissue at the time of tapping.

In addition, since the fourth incision surface 212 is concave in the incision groove 210, a part of the bone tissue is introduced into the incision groove 210 during self-tapping. At this time, the bone tissue introduced into the incision groove 210 is attached to the outer bone tissue of the incision groove 210 at the time of bone grafting, so that the fixing force of the first shaft portion 110 is further increased.

6, a fixture 300 according to another embodiment of the present invention is shown.

Referring to FIG. 1, a tapered portion is formed at a predetermined inclination angle with respect to an imaginary extension line extending upward from the first ridgeline of the first screw thread 111 at a position adjacent to the first ridgeline of the first screw thread 111 at the uppermost position, The slanted surface 301 is formed.

At this time, the inclined surface 301 is inclined so that its upper end is farther from the center of the first shaft 110 than the lower end, and the inclination angle is preferably 6 ° to 12 °. At this time, the inclined surface 301 is formed from the uppermost end of the first thread 111 to a position spaced along the first thread 111 by a predetermined length.

When the upper end of the first screw thread 111 enters the bone tissue when the first shaft part 110 is inserted into the bone tissue, the first shaft part 110 is constrained to the bone tissue by the inclined surface 301, The fixing force of the uniaxial portion 110 is increased. At this time, when the inclination angle of the inclined surface 301 is less than 6 degrees, a proper fitting strength to increase the fixing force with respect to the first axis 110 is not generated. When the inclination angle of the inclined surface 301 exceeds 12 degrees, When the shaft 110 is placed, the bone tissue is crushed to weaken the fixing force of the first shaft 110 with respect to the bone tissue. Therefore, the inclination angle of the inclined surface 301 is 6 to 12 degrees, preferably 10 degrees.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art.

Accordingly, the true scope of protection of the present invention should be determined only by the appended claims.

100: Fixture
110: first shaft portion
111: First thread
120: second shaft portion
121: Second thread
122: Cutting edge
123: 1st incision plane
124: 2nd incision plane

Claims (9)

A first shaft portion on which a first screw thread is formed on an outer peripheral surface;
A second screw thread extending downward from the lower end of the first shaft portion and having a pitch larger than the pitch of the first screw threads on an outer circumferential surface thereof and having a plurality of teeth spaced apart from each other along a circumferential direction at a lower end thereof to self- And a second shaft portion having a cutting edge of the cutting edge.
The method according to claim 1,
Wherein the cutting edges are drawn into a predetermined depth from the outer circumferential surface of the second shaft portion and extend along the longitudinal direction of the second shaft portion and are arranged radially with respect to the center of the second shaft portion.
3. The method of claim 2,
Wherein the cutting edge has a first incision surface extending in the radial direction of the second shaft portion and a second incision surface in the rotation direction in which the second axis portion is placed in the alveolar bone at an end portion of the first incision surface adjacent to the center of the second axis portion And a second incision surface extending in a direction opposite to the first incision surface, the second incision surface being orthogonal to the first incision surface.
3. The method of claim 2,
Wherein the first and second shaft portions are spaced apart from each other along a boundary line between the first and second shaft portions so as to reduce a load caused by a difference in shape from the second screw thread when the first screw thread is inserted into the alveolar bone, Wherein a plurality of incision grooves are formed.
5. The method of claim 4,
Wherein the cutout groove is extended in a predetermined depth from an outer circumferential surface of the first and second shaft portions and extends in an up and down direction so that upper and lower ends thereof are respectively located at the first and second shaft portions.
6. The method of claim 5,
Wherein the cutout grooves are radially arranged with respect to the center of the first and second shaft portions, and each of the cutout grooves is formed at a position opposed to a space between adjacent cutting edges.
The method according to claim 6,
Wherein the incision groove has a third incision surface extending in parallel with a radial direction of the first axis portion and an end portion of the first incision surface adjacent to the center of the first axis portion so that the first axis portion is placed in the alveolar bone And a fourth incision surface extending in a direction opposite to the rotation direction and recessed toward the center of the first axis portion.
8. The method according to any one of claims 2 to 7,
And the ridge of the first screw thread is tapered at a predetermined inclination angle with respect to an imaginary extension line extending upwardly of the ridge of the first screw thread at a position adjacent to the lower side.
9. The method of claim 8,
Wherein the ridge of the first screw thread is inclined so that the upper end thereof is farther away from the center of the first shaft than the lower end thereof, and the inclination angle is 6 ° to 12 °.

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