WO2015033680A1

WO2015033680A1 - Fixture, implant, and implant manufacturing method

Info

Publication number: WO2015033680A1
Application number: PCT/JP2014/069155
Authority: WO
Inventors: 石渡暉夫
Original assignee: 株式会社ナントー
Priority date: 2013-09-09
Filing date: 2014-07-18
Publication date: 2015-03-12
Also published as: JP2015051240A; TW201509384A

Abstract

A fixture (10), which is formed from titanium or a titanium alloy and is embedded in bone (2) and osseointegrated, wherein the external surface (10S) has grooves (M) formed with a width of 10 μm to 100 μm and a depth of 1 μm to 30 μm and the external surface (10S) is formed with a three-dimensional roughness (Sa) of 1 μm to 5 μm. The grooves (M) are formed by irradiating while scanning laser light on the external surface (10S). The external surface (10S) is roughened by etching with acid.

Description

Fixture, implant, and manufacturing method of implant

The present invention relates to a fixture, an implant, and a method for manufacturing the implant. For example, the present invention relates to a dental implant that is embedded in a jaw bone in the case of a root defect of a permanent tooth.
This application claims priority on September 9, 2013 based on Japanese Patent Application No. 2013-186756 filed in Japan, the contents of which are incorporated herein by reference.

Implants embedded in the body (particularly dental implants) have attracted attention. A dental implant is fixed in a hole provided in an alveolar bone when the root of a permanent tooth is lost due to decay or damage.
This dental implant is composed of a fixture (artificial tooth root) fixed to the alveolar bone and an abutment (abutment) screwed to the fixture. An implant crown (artificial dental crown) is attached to the abutment.

The outer surface of the fixture is a surface that directly contacts the bone, and a male screw is formed.
It has been clarified that there is a difference in bone bonding depending on the properties of the outer surface of the fixture. It has been reported that a fixture having a roughened outer surface can obtain higher bone bonding (bone adhesion) than a fixture having a smooth outer surface.

Also, it takes several weeks to several months for bones and fixtures to become osseointegration. If an excessive force is applied to the fixture during this period, the surrounding bone and mucosal tissue are damaged, so that the bone connection is delayed or becomes difficult to connect. For this reason, shortening of the joint period of a bone and a fixture is calculated | required.

JP 2010-5379 A

Even when the outer surface of the fixture is roughened, there may be cases where bone bonding is not sufficient. For this reason, there is a demand for a fixture that can provide higher bone adhesion.
Further, even when the outer surface of the fixture is roughened, it takes several weeks or more for bone bonding. For this reason, further shortening of the bone bonding period is required.

An object of the present invention is to provide a fixture, an implant, and a method for manufacturing the implant that can obtain high bone adhesion and can shorten the bone bonding period.

A first embodiment of the fixture of the present invention is a fixture that is formed of titanium or a titanium alloy, is embedded in bone, and is bone-bonded. The outer surface has a width of 10 μm to 100 μm and a depth of 1 μm to 30 μm. It has the following groove | channels, The three-dimensional roughness Sa of the said outer surface is formed in 1 to 5 micrometer, It is characterized by the above-mentioned.

A second embodiment of the fixture according to the present invention is a fixture that is formed of titanium or a titanium alloy, is embedded in bone, and is bone-bonded. The outer surface has a width of 10 μm to 100 μm and a depth of 1 μm to 30 μm. The surface area ratio Sdr of the outer surface is 50% or more and 500% or less.

An embodiment of the implant of the present invention is characterized by including the fixture according to the first or second embodiment of the present invention and an abutment that fits into the center hole of the fixture.

A first embodiment of a method for manufacturing an implant of the present invention is a method for manufacturing an implant that is formed of titanium or a titanium alloy and is embedded in a bone and bone-bonded to the outer surface of the implant. However, scanning is performed to form a groove having a width of 10 μm to 100 μm and a depth of 1 μm to 30 μm, and the outer surface is etched with an acid so that the three-dimensional roughness Sa is 1 μm to 5 μm. And a roughening step for roughening.

A second embodiment of the method for manufacturing an implant of the present invention is a method for manufacturing an implant that is formed of titanium or a titanium alloy and is embedded in a bone and bone-bonded, and irradiates the outer surface of the implant with a laser beam. And a groove forming step of forming a groove having a width of 10 μm to 100 μm and a depth of 1 μm to 30 μm, and etching the outer surface with an acid to have a surface area ratio Sdr of 50% to 500% And a roughening step for roughening.

A third embodiment of the method for producing an implant of the present invention is characterized in that, in the first or second embodiment, the laser beam is a fundamental wave of a solid laser.

According to a fourth embodiment of the method for producing an implant of the present invention, in any one of the first to third embodiments, the acid is any one of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, and a mixed acid thereof. And

According to the present invention, it is possible to realize a fixture, an implant, and a method for manufacturing an implant that can obtain high bone adhesion and can shorten the bone bonding period.

It is a figure which shows the implant 5 which concerns on embodiment of this invention. It is a figure which shows the fixture 10 which concerns on embodiment of this invention. It is the photograph which image | photographed the outer surface 10S (fine groove | channel M) of the fixture 10 by SEM, Comprising: (a) is a photograph of 200 times of magnification, (b) is a photograph of 2000 times of magnification. It is the photograph which image | photographed the preosteoblast C settled in the microgroove M with SEM.

Embodiments of the present invention will be described with reference to the drawings. The various dimensions shown in the following description are examples.

[Dental implant]
FIG. 1 is a view showing an implant 5 according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating the fixture 10 according to the embodiment of the present invention.

The implant 5 is a dental implant used in the dental field.
The implant 5 includes a fixture 10 that is fixed to the alveolar bone (bone) 2, and an abutment 8 that can be attached to and detached from the fixture 10.
An artificial crown 6 is attached to the abutment 8.

A male screw 12 is formed on the outer surface 10 </ b> S of the fixture 10. The fixture 10 is fixed to the alveolar bone 2 by screwing the male screw 12 into a hole formed in the alveolar bone 2.
An artificial crown 6 is attached to the outer surface of the abutment 8 using an adhesive or the like. A contact portion S between the fixture 10 and the abutment 8 is covered with the gum 4 or the alveolar bone 2. The contact surfaces of the fixture 10 and the abutment 8 are finished with high accuracy. The contact surfaces of the fixture 10 and the abutment 8 are in close contact with each other to prevent foreign matter from entering.

The fixture 10 is a columnar (shaft-shaped) member formed of titanium or a titanium alloy.
A male screw 12 is formed on the outer surface of the fixture 10. A center hole 13 is opened in the rear end surface of the fixture 10.
The shape (length, thickness, etc.) of the fixture 10 is arbitrary. The case where the external thread 12 and the center hole 13 do not exist may be sufficient.

FIG. 3 is a photograph of the outer surface 10S (fine groove M) of the fixture 10 taken with an SEM, wherein (a) is a photograph with a magnification of 200 times, and (b) is a photograph with a magnification of 2000 times.

A fine groove M is formed on the outer surface 10S of the fixture 10. The outer surface 10S includes a region where the male screw 12 is formed. Further, the outer surface 10S includes a tip surface and a male screw 12 (screw surface).

The fine groove (groove) M is formed in an arbitrary region (part) on the outer surface 10S of the fixture 10. The area where the fine groove M is formed may be one place or a plurality of places. The area of the region where the fine groove M is formed is arbitrary.
As shown in FIG. 2, the fine groove M may be formed on almost the entire outer surface 10S. In particular, it is preferable to form the fine groove M in a region of the outer surface 10S that directly contacts the alveolar bone 2.

The cross-sectional shape of the fine groove M is formed in a semicircular arc shape, for example. The cross-sectional shape of the fine groove M is not limited to a semicircular arc shape, and may be, for example, a triangle (isosceles triangle) or a rectangle.
Further, the outer surface 10S including the fine groove M is roughened.

The reason why the fine groove M is formed on the outer surface 10S is to facilitate fixing (adhering) the preosteoblasts to the outer surface 10S.
The reason for roughening the outer surface 10S including the microgrooves M is to promote the proliferation of preosteoblasts and shorten the bone bonding period. Moreover, it is for obtaining high bone adhesiveness by increasing the surface area of the outer surface 10S and invading anterior osteoblasts (osteoblasts).

The number of the fine grooves M is arbitrary. The number of fine grooves M may be one, but is preferably a large number (plural). The fine groove M is not limited to a straight line but may be a curved line.
When forming a plurality of fine grooves M, it is preferable to form the plurality of fine grooves M in parallel. The angle of the extending direction of the fine groove M with respect to the axial direction (longitudinal direction) of the fixture 10 is arbitrary.

The fine groove M is formed using a laser processing machine.
The fixture 10 is formed by machining a material of titanium or a titanium alloy such as lathe. The fine groove M is formed by irradiating the outer surface 10S of the fixture 10 with laser light and carving the outer surface 10S.
When forming a single fine groove M, the same portion is scanned once or more while irradiating a laser beam. As the number of scans increases, the depth and width of the fine groove M increase.

The fundamental wave of the solid laser is used for the laser beam. For example, a fundamental wave of Nd: YAG laser or YVO4 laser (solid laser: wavelength 1064 nm, fiber laser: 1090 nm) can be used. The light diameter (diameter) of the laser light is, for example, 5 to 50 μm.

The outer surface 10S is engraved by irradiating the outer surface 10S of the fixture 10 with laser light in the air. Thereby, the fine groove | channel M is formed in the outer surface 10S.

The width of the fine groove M is formed to be 10 μm or more and 100 μm or less. In particular, the width of the fine groove M is preferably 40 μm or more and 60 μm or less.
The reason why the width of the fine groove M is 10 μm or more is to reliably fix (adhere) the preosteoblasts inside the fine groove M.
The reason why the width of the fine groove M is 100 μm or less is to prevent the preosteoblast from spreading along the outer surface 10S.
When forming the plurality of fine grooves M, each may have a uniform width or a different width. Each fine groove M may have a uniform width or a different width in the longitudinal direction.

The depth of the fine groove M is 1 μm or more and 30 μm or less. In particular, the depth of the fine groove M is preferably 5 μm to 20 μm.
The reason why the depth of the fine groove M is 1 μm or more is to prevent the preosteoblasts from getting over the fine groove M and spreading along the outer surface 10S.
The reason why the depth of the microgroove M is 30 μm or less is higher than the microgroove M when the preosteoblasts proliferate and differentiate into osteoblasts (protrusively outward from the outer surface 10S). It is for doing so. That is, this is to prevent osteoblasts having an oval shape of about 20 to 30 μm from being buried in the fine groove M.
When forming the plurality of fine grooves M, each may have a uniform depth or a different depth. Moreover, each fine groove | channel M may be made into the uniform depth over a longitudinal direction, and may be made into a different depth.

When forming a plurality of fine grooves M, the intervals between the fine grooves M may be uniform or may be different.
The plurality of fine grooves M are preferably formed substantially in parallel so as not to cross each other. The reason is that the same state as the state of osteoblasts existing on the surface of the bone matrix is created on the outer surface 10S of the fixture 10. Osteoblasts are present in approximately one row on the surface of the bone matrix. For this reason, if the plurality of microgrooves M do not intersect, the same state as the state of osteoblasts existing on the bone matrix surface can be created on the outer surface 10S of the fixture 10. Thereby, promotion of the bone coupling | bonding of the fixture 10 and the alveolar bone 2 can be aimed at.

The roughening of the outer surface 10S including the fine grooves M is performed by immersing the fixture 10 in an acid. The outer surface 10S is roughened after the fine grooves M are formed.

Specifically, after the fine groove M is formed on the outer surface 10S, the fixture 10 is washed with water and brushing to remove deposits. Furthermore, the fixture 10 is ultrasonically cleaned with alcohol.
Next, the fixture 10 is immersed in hydrochloric acid for edging. For example, the concentration of hydrochloric acid is 1 to 20%, the liquid temperature is 30 ° C. to 80 ° C., and the immersion time is 10 minutes to 60 minutes. The acid used for edging may be other than hydrochloric acid. For example, sulfuric acid, hydrofluoric acid, nitric acid and the like, and mixed acids thereof can be used.
Finally, the fixture 10 is ultrasonically cleaned with pure water.

The outer surface 10S can be efficiently roughened by immersing the fixture 10 in acid. By roughening the outer surface 10S including the fine groove M, the fixture 10 and the bone tissue (alveolar bone 2) are easily brought into close contact with each other, and a strong bone bond can be obtained.

The roughened outer surface 10S has a three-dimensional roughness Sa (arithmetic mean roughness: ISO25178) of 1 μm or more and 5 μm or less. In particular, the three-dimensional roughness Sa is preferably 2 μm to 3 μm.
This is because by roughening the outer surface 10S, the osteoblasts are stimulated to promote differentiation into osteoblasts.

Alternatively, the roughened outer surface 10S has a surface area ratio Sdr (ratio of surface development area to nominal area: ISO25178) of 50% or more and 500% or less. In particular, the surface area ratio Sdr is preferably 200% to 400%.
This is because by roughening the outer surface 10S, the osteoblasts are stimulated to promote differentiation into osteoblasts.

The surface roughness and surface area ratio of the outer surface 10S are almost the same as the surface roughness and surface area ratio when osteoclasts destroy the bone matrix surface (bone resorption). That is, the same state as when osteoclasts settle (adhere) and propagate on the bone matrix surface to form bone is created on the outer surface 10S. Thereby, promotion of the bone coupling | bonding of the fixture 10 and the alveolar bone 2 can be aimed at.

[Settlement and proliferation of osteoblasts]
FIG. 4 is a photograph of the preosteoblast C that has settled in the microgroove M taken with an SEM.
FIG. 4 is an image taken by SEM of a few days after seeding the pre-osteoblasts C in the microgrooves M formed on the outer surface 10S of the fixture 10.

In order to promote the bone connection between the alveolar bone 2 and the fixture 10, it is effective to provide the outer surface 10S of the fixture 10 with a function of promoting bone formation.
Bone formation (calcification) is performed when differentiating from pre-osteoblasts to osteoblasts. For this reason, it is effective to give the outer surface 10S characteristics suitable for the proliferation of preosteoblasts. In addition, as a premise for the proliferation of preosteoblasts, it is effective to give the outer surface 10S characteristics suitable for the fixation (adhesion) of preosteoblasts.

When pre-osteoblasts are seeded on a flat surface, the pre-osteoblasts spread along the flat surface. For this reason, the fixation (adhesion) of anterior osteoblasts to a flat surface is delayed.
On the other hand, since the fixture 10 has the fine groove M formed on the outer surface 10S, the preosteoblasts seeded on the outer surface 10S do not spread along the surface, and the inside of the fine groove M Retained.

As shown in FIG. 4, the preosteoblast C settles inside the fine groove M without spreading along the outer surface 10 </ b> S of the fixture 10. For this reason, the front osteoblast C tends to be fixed (adhered) to the outer surface 10S.

Further, the outer surface 10S is roughened so that the three-dimensional roughness Sa is about 2 μm, or the three-dimensional roughness Sa is about 350%. By roughening the outer surface 10S, the osteoblast C can be stimulated to promote differentiation into osteoblasts. Therefore, the preosteoblast C tends to grow on the outer surface 10S.

The technical scope of the present invention is not limited to the above-described embodiment. In the range which does not deviate from the meaning of this invention, what added the various change to embodiment mentioned above is included. The specific materials and layer configurations described in the embodiments are merely examples, and can be changed as appropriate.

In the above embodiment, the laser beam by the Nd: YAG laser or the YVO4 laser is used as the method for forming the fine groove M, but is not limited thereto. For example, you may use the laser beam by another solid laser, or the laser beam by a harmonic.

In the above embodiment, the etching with acid is used as a method for roughening the outer surface 10S, but this is not a limitation.
The outer surface 10S of the fixture 10 may be simply irradiated with laser light to form the fine groove M. In this case, the three-dimensional roughness Sa of the outer surface 10S is about 1 μm, or the surface area ratio Sdr is about 50%.
A method of blasting the outer surface 10S may be used. In this case, the three-dimensional roughness Sa of the outer surface 10S is about 5 μm, or the surface area ratio Sdr is about 500%.

In the above-described embodiment, the dental implant (fixture) that is inserted into the alveolar bone perforation and fixed is described, but the implant (fixture) of the present invention is not limited to this.
The implant (fixture) of the present invention may be an implant (fixture) that is fixed in a contact state by being embedded in a bone of another part. For example, the implant (fixture) of the present invention may be applied as an artificial bone or a bone prosthetic material in order to compensate for a bone deficient part caused by fracture or benign tumor resection or cartilage removed by lumbar spine surgery. Good. Further, the implant (fixture) of the present invention may be employed for an artificial joint member, an osteosynthesis material used for fixing a fracture site, a spinal fixation device, and the like.

In the above embodiment, the fine grooves M are formed using laser light, but the present invention is not limited to this. The fine groove M may be formed by cutting. In particular, in an implant (fixture) other than a dental implant, a fine groove can be formed by cutting.

The implant of the present invention is not limited to having a fixture and an abutment, but may be only a fixture (not provided with an abutment) fixed to a bone.

2. Alveolar bone (bone) 4, gum, 5 implant, 8 abutment, 10 fixture, 10S outer surface, M fine groove (groove)

Claims

A fixture that is formed of titanium or a titanium alloy and is embedded in bone and bone-bonded,
A groove having a width of 10 μm to 100 μm and a depth of 1 μm to 30 μm on the outer surface;
A fixture having a three-dimensional roughness Sa of the outer surface of 1 μm or more and 5 μm or less.
A fixture that is formed of titanium or a titanium alloy and is embedded in bone and bone-bonded,
A groove having a width of 10 μm to 100 μm and a depth of 1 μm to 30 μm on the outer surface;
A fixture having a surface area ratio Sdr of the outer surface of 50% to 500%.
The fixture according to claim 1 or 2,
An abutment that fits into the center hole of the fixture;
An implant comprising:
A method of manufacturing an implant formed of titanium or a titanium alloy and embedded in a bone and bone-bonded,
A groove forming step of forming a groove having a width of 10 μm or more and 100 μm or less and a depth of 1 μm or more and 30 μm or less by scanning the outer surface of the implant while applying laser light;
A roughening step of etching the outer surface with an acid to roughen the three-dimensional roughness Sa to 1 μm or more and 5 μm or less;
The manufacturing method of the implant which has this.
A method of manufacturing an implant formed of titanium or a titanium alloy and embedded in a bone and bone-bonded,
A groove forming step of forming a groove having a width of 10 μm or more and 100 μm or less and a depth of 1 μm or more and 30 μm or less by scanning the outer surface of the implant while applying laser light;
A roughening step of etching the outer surface with an acid to roughen the surface area ratio Sdr to 50% or more and 500% or less;
The manufacturing method of the implant which has this.
The implant manufacturing method according to claim 4 or 5, wherein the laser beam is a fundamental wave of a solid-state laser.
The method for producing an implant according to any one of claims 4 to 6, wherein the acid is any one of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, and a mixed acid thereof.