WO2019054832A2

WO2019054832A2 - Peek-based dental implant having surface roughness

Info

Publication number: WO2019054832A2
Application number: PCT/KR2018/010931
Authority: WO
Inventors: 박재준; 최홍영
Original assignee: 오스템임플란트 주식회사
Priority date: 2017-09-18
Filing date: 2018-09-17
Publication date: 2019-03-21
Also published as: KR20190031783A; WO2019054832A3

Abstract

One embodiment of the present invention provides a dental implant having the surface thereof blasted and etched, wherein the dental implant comprises polyether ether ketone, the Ra of the profile of the surface is 0.6 to 3.3 μm, and the Rc of the profile elements of the surface is 2.6 to 15.0 μm.

Description

PEEK dental implants with surface roughness

The present invention relates to a dental implant, and more particularly, to a dental implant made of PEEK or a composite material containing the PEEK having a certain level of surface roughness.

Dental implants inserted into the jawbone for attachment of artificial teeth have been successfully used for a long time. Currently commonly used dental implants are made of titanium or an alloy thereof, which is suitable for living body, has sufficiently low elasticity, and is relatively high in strength.

In addition to biocompatibility and mechanical properties, osteo-integration characteristics of dental implants are very important. Good bone fusion characteristics mean that the implant is fixed to the bone to achieve initial stability and then a permanent bond is created between the implant and bone within a short treatment period.

When titanium is used as an implant material, the osseointegration characteristic can be obtained by proper treatment of the implant surface. For this purpose, the titanium surface is mechanically roughened by, for example, sandblasting, grinding or etching. Alternatively, the surface may be treated by an additive method such as coating with a textured surface or coating with a biocompatible material.

However, in the aesthetic viewpoint, titanium dental implants have a disadvantage that they are inharmonious with the natural teeth because they are dark when the implants are exposed due to gingival recession. On the other hand, the color of the ceramic material may be close to the color of the natural teeth, and efforts have been made to make even a part of the implants observed with the naked eye after the implantation into a ceramic material. Despite their advantages in terms of color, ceramic dental implants have low fatigue stability and poor cracking properties.

On the other hand, it is known that an implant of a polymer material such as polyether ether ketone (PEEK) is advantageous in terms of aesthetics and resistance to cracking, and is partially applied to an orthopedic implant material. However, The implant of the material has only a surface roughness imparted by mechanical processing for imparting a proper shape, so that there is a problem that the bone fusion and osteogenesis characteristics are lower than those of the conventional titanium implant.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a dental implant having not only aesthetic, crack resistance but also bone formation characteristics.

According to an aspect of the present invention, there is provided a dental implant having a blasted and etched surface, wherein the dental implant comprises a polymer, the arithmetic average height (Ra) of the contour curve of the surface is 0.6 to 3.3 m , And an average height (Rc) of the contour curve elements is 2.6 to 15.0 占 퐉.

In one embodiment, the average height of the contour elements may be between 3.0 and 12.0 m.

In one embodiment, the arithmetic average height of the contour curve may be 0.7-2.

In one embodiment, the average height Rc of the contour elements may be between 4.5 and 8.5 microns.

In one embodiment, the arithmetic mean height (Ra) of the outline curve may be 1.1 to 2.5 占 퐉.

In one embodiment, the polymer may be polyetheretherketone (PEEK).

The surface of the dental implant according to an aspect of the present invention is a surface of a dental implant which is formed by blasting and etching treatment, and a macro surface (including a first groove) and a micro surface (a second groove (Ra) of the contour curve, and an average height (Rc) of the contour curve elements, thereby providing excellent biocompatibility including bone formation characteristics after implantation .

In addition, when the surface of the dental implant includes a polymer such as polyether ether ketone, it has not only excellent biocompatibility, but also has a color similar to that of a tooth. Therefore, great.

It should be understood that the effects of the present invention are not limited to the effects described above, but include all effects that can be deduced from the description of the invention or the composition of the invention set forth in the claims.

1 is a diagram illustrating a method of measuring an arithmetic average height Ra of an outline curve and an average height Rc of a contour curve element according to an embodiment of the present invention.

2 is a schematic view of the surface of a dental implant according to an embodiment of the present invention.

3 shows the measurement results of the surface roughness of polyetheretherketone (PEEK) specimens according to Examples and Comparative Examples of the present invention.

4 is a SEM image of a surface of a polyetheretherketone (PEEK) specimen according to an embodiment of the present invention and a comparative example.

5 is an image obtained by a non-contact measurement method for the surface of a polyetheretherketone (PEEK) specimen according to an embodiment of the present invention.

6 is a SEM image of a surface of a dental implant according to the preparation example of the present invention and the comparative preparation example.

FIG. 7 shows the results of measurement of the binding force on the bone interface of the dental implant according to the production example of the present invention and the comparative preparation example.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "indirectly connected" . Also, when an element is referred to as " comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

According to an aspect of the present invention, there is provided a dental implant having a blasted and etched surface, wherein the dental implant comprises a polymer, the arithmetic average height (Ra) of the contour curve of the surface is 0.6 to 3.3 m , And an average height (Rc) of the contour curve elements is 2.6 to 15.0 占 퐉. The dental implant may be composed of a polymer mixture containing polyether ether ketone, or may be composed of polyether ether ketone.

The arithmetic average height Ra of the outline curve shown in Fig. 1 (a) is an average value for the center line, and is an average value of the absolute values of the deviations from the center line to the measurement curve. Ra is most widely used as a roughness parameter because it is suitable for evaluation of gloss, surface strength, surface treatment, friction force, electrical contact resistance, etc. However, exceptional peaks and / or valleys do not affect Ra, Since Ra does not provide information on the roughness type, there is a limitation in specifying the actual shape of the surface roughness of the implant and the physical properties depending thereon.

On the other hand, the average height Rc of the contour curve elements shown in Fig. 1 (b) is based on the rule of JIS B 0601 (2001), and is a value obtained by averaging the height of contour curve elements at the reference length lr. Depending on the shape of the irregularities formed on the surface, the outline curve may include a plurality of peaks and adjacent valleys. Wherein said contour curve element is an element whose distance from an adjacent peak or valley is less than 1% of the reference length to noise less than 10% of Rz which is a sum of a maximum value of peak height of said contour curve and a maximum value of valley depth, And points to the remaining element after removing it. That is, the average height Rc of the contour curve elements is a value obtained by averaging the height of the contour curve elements excluding the elements classified by the noise. Since Rc is measured from the contour curve element which is the sum of the peak height and the depth of the valley, the shape of the surface roughness at the reference length and the information resulting therefrom, such as aesthetics, adhesiveness, Can be obtained.

Generally, Ra and Rc of the surface treated under the same conditions have a similar tendency, but since the information on the surface roughness obtained from Ra and Rc is partly different, both of them are measured and each of them is adjusted to a certain range The desired physical properties can be optimized and implemented.

The dental implant has a surface treated by sandblasting and etching, and the arithmetic mean height (Ra) of the outline curve of the surface is 0.6 to 3.3 탆, preferably 0.7 to 2.9 탆, more preferably 1.1 Lt; / RTI > When the Ra of the surface is in the above range, the surface structure of the dental implant becomes similar to the natural bone, so that the osseointegration rate on the surface of the implant can be improved, the failure rate after the procedure can be lowered, and the procedure time can be shortened.

In addition, the average height Rc of the contour curve elements of the surface of the dental implant may be 2.6 to 15.0 m, preferably 3.0 to 12.0 m, and more preferably 4.5 to 8.5 m. Since Ra can not reflect the height and / or depth of an exceptional peak and / or valley, Ra alone can not specify the shape of the surface roughness, and accordingly the physical properties due to the shape of the surface roughness There is a problem that is difficult to achieve. Therefore, by adjusting the range of Ra as well as the range of Rc as described above, it is possible to impart the surface shape and surface roughness of the implant, which is difficult to achieve with only Ra.

The surface may include one selected from the group consisting of polymers, ceramics, metals, and combinations of two or more thereof, and may preferably include a polymer. The polymer may be a super engineering plastic, a engineering plastic, a general purpose plastic, or a combination thereof capable of implementing a color similar to teeth, and preferably, it may be polyether ether ketone (PEEK), but is not limited thereto.

In addition, the dental implant may further include a center portion including one selected from the group consisting of polymers, ceramics, metals, and combinations of two or more thereof.

Unlike the surface, the central portion is not exposed to the outside regardless of before and after the procedure, especially after the procedure, so that the hue is not limited to a tooth-like one. For example, the central portion may be conventional titanium or an alloy thereof, or may be a ceramic such as zirconia. Preferably, if the surface comprises a polymer, the central portion may comprise a polymer to provide process advantages and to enhance bonding at the surface and core interface. The polymer contained in the central portion may be a super engineering plastic, an engineering plastic, a general purpose plastic, or a combination thereof. Preferably, the polymer may be polyether ether ketone (PEEK).

The surface and the center portion may be fabricated as separate components and then combined to form a dental implant. If necessary, the surface and the center portion may be mechanically processed from one circular shape and then sandblasted and / or etched, A single dental implant in which the central portion is integrally formed may be constituted. Preferably, the dental implant may have the surface and the central portion integrally formed in order to achieve process advantages and to fundamentally block the problem of the bonding force at the surface and the central interface.

The surface roughness of the dental implant, that is, the arithmetic mean height (Ra) of the outline curve of the above range and the mean height (Rc) of the outline curve element are determined in a dental implant originally made in the form of a dental implant For example, by sandblasting and etching.

The polishing means abrasive blasting the surface of the untreated dental implant with an abrasive grain having an average particle diameter of 25 to 1,000 μm to form a macro surface on the surface. As used herein, the term " macro surface " refers to a structure comprising a first groove formed on the surface by the abrasive particles. The surface area is increased by the effect of the particles sprayed on the surface through the polishing, and the bone interface strengthening effect is increased by the irregular effect and the cell reaction is activated on the rough surface.

Among the polishing methods, sand blasting is a method in which a surface of a specific particle is sprayed onto the surface of an implant to form a rough surface. As the medium, alumina (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), Calcium oxide (Ca ₃ PO ₄ ), hydroxyapatite (HA), and the like. The ejection pressure of the medium may be 2.0 to 5.0 MPa, preferably 2.5 to 4.5 MPa, more preferably 2.5 to 4.0 MPa, and the ejection time of the medium may be 1 to 60 seconds, 60 seconds. In addition, the implant may be immersed in an acid aqueous solution, for example, an aqueous nitric acid solution, at a predetermined concentration to remove the medium remaining on the surface after spraying the medium.

The micro surface can be formed on the macro surface by treating the macro surface formed on the surface of the dental implant by the polishing with an etching solution. As used herein, the term " micro-surface " means a structure including a second groove smaller in size than the first groove formed on the macro surface.

The etchant may comprise a permanganic acid compound. The permanganic acid compound may be an alkali metal salt, and preferably, it may be a sodium salt or a potassium salt. The content of the permanganic acid compound in the etching solution may be 0.001 to 20 wt%, preferably 0.01 to 10 wt%, more preferably 0.1 to 5 wt%.

In the permanganic acid compound, the etching solution may become alkaline due to the influence of counter ions. Since the alkaline etching solution adversely affects the surface of the implant, it is preferable to add a certain amount of acid to the etching solution to maintain the acidity.

The acid which can be used in combination with the permanganic acid compound in the etching solution may be an organic acid or an inorganic acid, preferably an inorganic acid. The organic acid may be, for example, formic acid, acetic acid, propionic acid or the like, preferably acetic acid, but is not limited thereto. The inorganic acid may be, for example, phosphoric acid, nitric acid, sulfuric acid and the like, preferably phosphoric acid, but is not limited thereto. The content of the acid in combination with the permanganic acid compound in the etching solution may be 1 to 50 wt%, preferably 5 to 25 wt%.

The etchant may contain residual water in addition to the permanganic acid compound and an acid used in combination with the permanganic acid compound, and the temperature of the etchant may be adjusted to room temperature (about 25 ° C) during etching.

2 is a schematic view of the surface of a dental implant according to an embodiment of the present invention. 2, a macroscopic surface including a first groove may be formed on the surface of the dental implant by the polishing, and a plurality of grooves may be formed on the surface of the dental implant, 2 < / RTI > grooves.

When the surface includes both the macro surface and the micro surface, Ra and Rc of the above range can be realized, thereby improving osseointegration and bone formation characteristics including biocompatibility after the implant treatment.

Hereinafter, embodiments of the present invention will be described in detail.

Comparative Example

A polyether ether ketone (PEEK) round specimen was mechanically processed to prepare a disc (cylindrical) specimen having a diameter of 6 mm and a thickness of 2 mm.

Example 1

A polyetheretherketone (PEEK) specimen in the form of a disk (cylinder) having a diameter of 6 mm and a thickness of 2 mm was prepared and a hydroxyapatite (HA) powder having an average particle diameter of 0.5 mm on the surface was pressed at a pressure of 10 to 60 Lt; / RTI > After the spraying, a first groove (macroscopic surface) was formed on the surface of the specimen by immersing in a nitric acid aqueous solution having a concentration of 15% by weight for 2 seconds in order to remove the hydroxyapatite powder from the surface of the specimen.

Example 2

The test piece having the first grooves formed in Example 1 was immersed in an aqueous acid solution containing 2 wt% of potassium permanganate (KMnO ₄ ), 10 wt% of phosphoric acid (H ₃ PO ₄ ) and a remaining amount of water at room temperature (about 25 ° C) And a second groove (micro-surface) smaller in size than the first groove was formed on the surface of the specimen by soaking for 1.5 minutes.

Example 3

The surface of the PEEK specimen was treated in the same manner as in Example 2 except that hydroxyapatite (HA) powder was sprayed at a pressure of 3.0 MPa.

Example 4

The surface of the PEEK specimen was treated in the same manner as in Example 2 except that hydroxyapatite (HA) powder was sprayed at a pressure of 3.5 MPa.

Example 5

The surface of the PEEK specimen was treated in the same manner as in Example 2 except that hydroxyapatite (HA) powder was sprayed at a pressure of 4.0 MPa.

Example 6

The surface of the PEEK specimen was treated in the same manner as in Example 2 except that hydroxyapatite (HA) powder was sprayed at a pressure of 4.5 MPa.

Experimental Example 1: Surface Characteristics of Specimen According to Injection Pressure

The surface roughness of the specimen was measured with a contact type roughness tester (FTSS S5, Taylor Hobson Ltd, UK). For this purpose, two specimens were randomly selected in each of the comparative examples and the examples, and three different specimens were measured. The measurement length and cutoff length were measured to be 2 mm and 0.025 mm, respectively, and the results were obtained using Gaussian filtering.

3 shows the measurement results of the surface roughness of polyetheretherketone (PEEK) specimens according to Examples and Comparative Examples of the present invention. Referring to FIG. 3, Ra and Rc before the formation of the macroscopic surface were 0.169 .mu.m and 0.644 .mu.m, respectively, and slightly increased to 0.807 .mu.m and 3.295 .mu.m, respectively, in Example 1 in which macroscopic surface was formed by hydroxyapatite injection. On the other hand, in Examples 2 to 6 in which the aqueous solution of the acid was further treated with the specimen of Example 1, Ra and Rc were 1.235 to 2.631 mu m and 5.384 to 10.984 mu m, respectively, which was significantly increased as compared with Example 1. Particularly, In Examples 5 and 6, in which the injection pressure was relatively high at 4.0 MPa and 4.5 MPa, Ra and Rc were respectively highest.

4 is a SEM image of a surface of a polyetheretherketone (PEEK) specimen according to an embodiment of the present invention and a comparative example. Referring to FIG. 4, the surface roughness of Example 6 was significantly increased as compared with the comparative example, and the results are also consistent with the measured values of Ra and Rc.

Example 7

The surface of the PEEK specimen was treated in the same manner as in Example 6 except that the content of potassium permanganate (KMnO 4) in the aqueous acid solution was changed to 4 wt%.

Example 8

The surface of the PEEK specimen was treated in the same manner as in Example 6 except that the content of potassium permanganate (KMnO 4) in the aqueous acid solution was changed to 5 wt%.

Example 9

The surface of the PEEK specimen was treated in the same manner as in Example 6 except that the content of potassium permanganate (KMnO 4) in the aqueous acid solution was changed to 6 wt%.

Experimental Example 2: Potassium permanganate ( KMnO4 The surface characteristics of the specimen

5 is an image obtained by a non-contact measurement method for the surface of a polyetheretherketone (PEEK) specimen according to an embodiment of the present invention. 5, only the macroscopic surface (blue region) due to polishing was observed in Example 1. On the other hand, in Examples 2 to 6, a micro surface (red region) formed by etching was formed on the macro surface formed by polishing, Were observed.

Comparative Manufacturing Example

A PEEK implant (untreated) having an untreated surface was prepared using the method of the above comparative example.

Manufacturing example

Using the method of Example 6 above, the surface of a PEEK implant (untreated) with an untreated surface was treated.

Experimental Example 3: Surface Characteristics of PEEK Implant

6 is a SEM image of a surface of a dental implant according to the preparation example of the present invention and the comparative preparation example. 6, a large number of unnecessary protruding burrs were observed on the surface of the polished PEEK implant in the comparative production example, whereas on the surface of the polished and etched PEEK implant in the manufacturing example, these burrs were substantially completely removed .

Experimental Example 4: Bone interface strength of PEEK implants

Twenty PEEK implants according to the preparation examples and comparative preparation examples were implanted into the rabbit tibia with a torque of 1 N · m each. Then, after the lapse of 2 weeks (14 days) and 4 weeks (28 days), the torque required to remove each of the implants from each rabbit tibia was measured, and the average value of each torque was measured and shown in FIG. Referring to FIG. 7, it can be seen that the PEEK implants processed in the preparation example provide about 40 to 50% higher interfacial bond strength (bond strength of the bone formed on the implant surface and the implant surface) than the comparative preparation example.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims

In a dental implant having a blasted and etched surface,

Wherein the dental implant comprises a polymer,

The arithmetic mean height (Ra) of the contour curve of the surface is 0.6 to 3.3 占 퐉,

Dental implants with an average height (Rc) of contour curve elements of 2.6 to 15.0 μm.
The method according to claim 1,

And an average height Rc of the contour curve elements is 3.0 to 12.0 占 퐉.
3. The method of claim 2,

And an arithmetic mean height (Ra) of the contour curve is 0.7 to 2.9 占 퐉.
The method according to claim 1,

Wherein the contour curve elements have an average height Rc of 4.5 to 8.5 占 퐉.
5. The method of claim 4,

Wherein the arithmetic average height (Ra) of the contour curve is 1.1 to 2.5 占 퐉.
The method according to claim 1,

Wherein the polymer is polyetheretherketone (PEEK).