KR20200016310A - A dental implant comprising polyetheretherketone havnig a surface roughness - Google Patents

Abstract

In a dental implant having a surface treated by blasting and etching, the dental implant according to one embodiment of the present invention comprises polyetheretherketone, wherein an arithmetic mean height (Ra) of a contour curve of the surface is 0.6 to 3.3 μm and an average height (Rc) of a contour curve element of 2.6 to 15.0 μm. According to the present invention, biocompatibility of the implant is excellent after an implant procedure.

Description

PEEK Dental Implant with Surface Roughness {A DENTAL IMPLANT COMPRISING POLYETHERETHERKETONE HAVNIG A SURFACE ROUGHNESS}

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

Dental implants that are inserted into the jaw bone, such as for the attachment of artificial teeth, have been used successfully for a long time. Currently used dental implants are made of titanium or its alloys, which are suitable for living bodies, have a sufficiently low modulus of elasticity, and are relatively high in strength.

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

When titanium is used as the implant material, osteofusion properties can be obtained by appropriate treatment of the implant surface. For this purpose the titanium surface is mechanically roughened, for example, by sandblasting, grinding or etching. Alternatively, the surface may be treated by additive methods, such as coating with a textured surface or coating a material with good biocompatibility.

However, from the aesthetic point of view, the dental implant of titanium material has a disadvantage in that it is inconsistent with the color of natural teeth because it is dark when the implant is exposed due to gingival contraction. On the other hand, the color of the ceramic material may be close to the color of the natural tooth, and efforts have been made to make the ceramic material even a part of the implant visible to the naked eye after insertion. Despite their advantages in terms of color, dental implants of ceramic materials have a low fatigue stability, and thus have a weak cracking property.

On the other hand, the implant of a polymer material, for example, polyether ether ketone (PEEK) material is known to be advantageous in terms of aesthetics and crack resistance, and has been partially applied as an orthopedic implant material, but PEEK developed until now Since the implant of the material has only the surface roughness given by mechanical processing to impart an appropriate shape, there is a problem that the fusion and bone formation characteristics are lower than those of the conventional titanium implant.

The present invention is to solve the above-mentioned problems of the prior art, an object of the present invention to provide a dental implant excellent in aesthetic properties, crack resistance as well as bone formation characteristics.

In one aspect of the invention, in the dental implant having a surface treated by blasting and etching, the dental implant comprises a polymer, the arithmetic mean height (Ra) of the contour curve of the surface is 0.6 ~ 3.3μm It provides a dental implant with an average height (Rc) of contour curve elements of 2.6-15.0 μm.

In one embodiment, the average height of the contour curve element may be 3.0 ~ 12.0μm.

In one embodiment, the arithmetic mean height of the contour curve may be 0.7 ~ 2.9μm.

In one embodiment, the average height (Rc) of the contour curve element may be 4.5 ~ 8.5μm.

In one embodiment, the arithmetic mean height (Ra) of the contour curve may be 1.1 ~ 2.5μm.

In one embodiment, the polymer may be polyether ether ketone (PEEK).

The surface of the dental implant according to an aspect of the present invention is a macro surface (including a first groove) formed through blasting and etching treatment and a micro surface (second groove smaller in size than the first groove formed in the macro surface And arithmetic mean height Ra of a range of contour curves and average height Rc of contour curve elements accordingly, and thus have excellent biocompatibility including implantation characteristics after implantation. .

In addition, when the surface of the dental implant includes a polymer, for example, polyether ether ketone, not only has excellent biocompatibility but also has a color similar to that of teeth, so that aesthetic satisfaction is also higher than that of conventional titanium or its alloys. great.

It is to be understood that the effects of the present invention are not limited to the above effects, and include all effects deduced from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a diagram illustrating a method of measuring an arithmetic mean height Ra of a contour curve and an average height Rc of a contour curve element according to an embodiment of the present invention.
Figure 2 is a schematic view of the surface of the dental implant according to an embodiment of the present invention.
Figure 3 shows the surface roughness measurement results of the polyether ether ketone (PEEK) specimens according to the Examples and Comparative Examples of the present invention.
Figure 4 is an SEM image of the surface of the polyether ether ketone (PEEK) specimens according to the Examples and Comparative Examples of the present invention.
5 is an image obtained by a non-contact measuring method for the surface of a polyether ether ketone (PEEK) specimen according to an embodiment of the present invention.
6 is a SEM image of the surface of the dental implant according to the preparation and comparative example of the present invention.
Figure 7 shows the results of measuring the binding force on the bone interface of the dental implants according to the preparation and comparative examples of the present invention.

Hereinafter, with reference to the accompanying drawings will be described the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is "connected" to another part, this includes not only "directly connected" but also "indirectly connected" with another member in between. . In addition, when a part is said to "include" a certain component, it means that it may further include other components, without excluding the other components unless otherwise stated.

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

In one aspect of the invention, in the dental implant having a surface treated by blasting and etching, the dental implant comprises a polymer, the arithmetic mean height (Ra) of the contour curve of the surface is 0.6 ~ 3.3μm It provides a dental implant with an average height Rc of the contour curve element of 2.6-15.0 μm. The dental implant may be made of a polymer mixture including polyetheretherketone, or may be made of polyetheretherketone.

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

The arithmetic mean height Ra of the contour curve shown in Fig. 1 (a) is an average value with respect to the center line, which is the average of the sum of the absolute values of the deviations from the center line to the measurement curve. Ra is the most widely used roughness parameter because it is suitable for evaluation of gloss, surface strength, surface treatment, frictional force, electrical contact resistance, etc., but exceptional peak and / or valley does not affect Ra. Since Ra does not provide information on the roughness type, there is a limit in specifying the actual shape of the surface roughness of the implant and the properties depending thereon.

In contrast, the average height Rc of the contour curve element shown in FIG. 1B is based on JIS B 0601 (2001), and is a value obtained by averaging the height of the contour curve element at the reference length lr. Depending on the shape of the irregularities formed on the surface, the contour curve may include a number of peaks and valleys adjacent thereto. The contour curve element noises an element less than 10% of Rz, which is the sum of the maximum value of the peak height of the contour curve and the maximum value of the valley depth at the reference length, and an element whose distance between adjacent peaks or valleys is less than 1% of the reference length. To identify the element remaining after removing it. That is, the average height Rc of the contour curve element is a value obtained by averaging the heights of the contour curve elements except the elements classified as the noise. Rc is measured from the contour curve element, which is the sum of the height of the peak and the depth of the valley. You can get it.

In general, Ra and Rc of the surface treated under the same conditions have a similar tendency, but since some information on the surface roughness obtained from Ra and Rc is different, both are measured and each of them is adjusted to a certain range. This can be achieved by optimizing the desired physical properties.

The dental implant has a surface treated by sand blasting and etching, and the arithmetic mean height Ra of the contour curve of the surface is 0.6-3.3 μm, preferably 0.7-2.9 μm, more preferably 1.1 It may be ~ 2.5μm. When the Ra of the surface is in the above range, the surface structure of the dental implant may be similar to natural bone, so that the rate of bone fusion at the surface of the implant may be improved, and the failure rate after the procedure may be shortened and the procedure time may be shortened.

In addition, the average height Rc of the contour curve element on the surface of the dental implant may be 2.6-15.0 μm, preferably 3.0-12.0 μm, more preferably 4.5-8.5 μm. Ra cannot reflect the exceptional peak and / or valley height and / or depth, so Ra alone cannot specify the shape of the surface roughness, and therefore the properties due to the shape of the surface roughness There is a problem that is difficult to achieve. Therefore, by adjusting the range of Rc as well as Ra of the surface as described above, it is possible to give the surface shape and surface roughness of the implant that is difficult to achieve only by Ra.

The surface may include one selected from the group consisting of a polymer, a ceramic, a metal, and a combination of two or more thereof, and preferably, may include a polymer. The polymer may be a super engineering plastic, an engineering plastic, a general purpose plastic, or a combination thereof, which may implement a color similar to a tooth, and preferably, may be polyether ether ketone (PEEK), but is not limited thereto.

In addition, the dental implant may further include a central portion including one selected from the group consisting of a polymer, a ceramic, a metal, and a combination of two or more thereof.

Unlike the surface, the central part is not exposed to the outside regardless of before or after the procedure, especially after the procedure, so that the color is not limited to that similar to the tooth. For example, the central portion may be conventional titanium or an alloy thereof, or may be a ceramic such as zirconia. Preferably, when the surface comprises a polymer, the central portion may include a polymer in order to achieve process advantages and to improve bonding at the surface and central interface. The polymer included in the center may be a super engineering plastic, an engineering plastic, a general purpose plastic, or a combination thereof, and preferably, polyether ether ketone (PEEK), but is not limited thereto.

The surface and the central portion may each be fabricated as separate components and then combined to form a dental implant, as required, mechanically processed from one circle and then sandblasted and / or etched to form the surface and The central portion may constitute a single dental implant integrally. Preferably, the dental implant may be integrally formed with the surface and the central portion in order to achieve process advantages and to fundamentally contain the problem of bonding forces at the surface and central interface.

The surface roughness of the dental implant, i.e., the arithmetic mean height Ra of the contour curve and the average height Rc of the contour curve element of the dental implant, is in the form of a dental implant primarily manufactured in the form of a dental implant. By sand blasting and etching.

The polishing refers to a process of forming a macro surface on the surface by abrasive blasting the surface of the untreated dental implant with abrasive grains having an average particle diameter of 25 to 1,000 μm. As used herein, the term "macro surface" means a structure comprising a first groove formed in the surface by the abrasive particles. The surface area is increased by the effect of the particles sprayed on the surface through the polishing to increase the bone interface binding force due to the irregularities effect, and the reaction of the cells on the rough surface is activated.

Sand blasting (Sand Blasting) of the polishing method by spraying a medium of a specific particle on the surface of the implant to form a rough surface, the medium is alumina (Al ₂ O ₃ ), titanium oxide (TiO ₂ ) with excellent biocompatibility ), Calcium oxide (Ca ₃ PO ₄ ), hydroxyapatite (HA) and the like. The injection 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 injection time of the medium is 1 to 60 seconds, preferably 10 to It may be 60 seconds. In addition, the implant may be immersed in an aqueous solution of an acid, for example, an aqueous solution of nitric acid, to remove the medium remaining on the surface after the injection of 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 with the etching solution by the polishing. As used herein, the term "micro surface" means a structure including a second groove smaller in size than the first groove formed in the macro surface.

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

The permanganate compound may become alkaline due to the influence of counter ions. Since the alkaline etching solution may adversely affect the surface of the implant, it is preferable to add an amount of acid to the etching solution to maintain acidity.

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

The etchant may include a residual amount of water in addition to the permanganic acid compound and the acid used in combination therewith, and may adjust the temperature of the etchant at room temperature (about 25 ° C.) during etching.

Figure 2 is a schematic view of the surface of the dental implant according to an embodiment of the present invention. Referring to FIG. 2, a macro surface including a first groove may be formed on the surface of the dental implant by the polishing, and the agent having a smaller size than the first groove formed on the macro surface by the subsequent etching. It is possible to form a micro surface comprising two grooves.

When the surface includes both the macro surface and the micro surface, it is possible to implement Ra and Rc in the above range, thereby improving bone fusion, bone formation characteristics including biocompatibility after implantation.

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

Comparative example

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

Example 1

Prepare a polyether ether ketone (PEEK) specimen with a diameter of 6 mm and a thickness of 2 mm, and prepare a hydroxyapatite (HA) powder with an average particle diameter of 0.5 mm on the surface at a pressure of 2.5 MPa from 10 to 60 Sprayed for seconds. After spraying, the first groove (macro surface) was formed on the surface of the specimen by immersion for 2 seconds in an aqueous 15% by weight nitric acid solution to remove the hydroxyapatite powder from the surface of the specimen.

Example 2

The specimen in which the first grooves obtained in Example 1 were formed was added to an acid aqueous solution at room temperature (about 25 ° C.) containing 2% by weight of potassium permanganate (KMnO ₄ ), 10% by weight of phosphoric acid (H ₃ PO ₄ ), and a residual amount of water. Immersion was performed for 1.5 minutes to form a second groove (micro surface) having a smaller size than the first groove on the surface of the specimen.

Example 3

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

Example 4

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

Example 5

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

Example 6

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

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

Surface roughness of the specimens was measured by a contact roughness measuring instrument (FTSS S5, Taylor Hobson Ltd, UK). To this end, two specimens were randomly selected in each of the comparative examples and examples, and three different sites were measured. The measurement length and the cutoff length were measured to be 2 mm and 0.025 mm, respectively, and then Gaussian filtering was used to obtain a result.

Figure 3 shows the surface roughness measurement results of the polyether ether ketone (PEEK) specimens according to the Examples and Comparative Examples of the present invention. Referring to FIG. 3, Ra and Rc before forming the macro surface were the lowest at 0.169 μm and 0.644 μm, respectively, and in Example 1 in which the macro surface was formed by hydroxyapatite injection, it was slightly increased to 0.807 μm and 3.295 μm, respectively. On the other hand, in Examples 2 to 6 in which the acid solution was additionally treated to the specimen of Example 1, Ra and Rc were 1.235 to 2.631 μm and 5.384 to 10.984 μm, respectively. In Examples 5 and 6, where the injection pressures were relatively high at 4.0 MPa and 4.5 MPa, Ra and Rc were measured highest.

Figure 4 is an SEM image of the surface of the polyether ether ketone (PEEK) specimens according to the Examples and Comparative Examples of the present invention. Referring to FIG. 4, the surface roughness of Example 6 was significantly increased compared to that of the comparative example, and these results were found to correspond to 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 acid aqueous 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 acid aqueous solution was changed to 6 wt%.

Experimental Example 2: Potassium Permanganate (KMnO ₄ Surface Characteristics of Specimen with Different Concentrations

5 is an image obtained by a non-contact measuring method for the surface of a polyether ether ketone (PEEK) specimen according to an embodiment of the present invention. Referring to FIG. 5, in Example 1, only the macro surface (blue region) by polishing was observed, whereas in Examples 2 to 6, the micro surface (red region) formed by etching on the macro surface formed by polishing was observed. This was further observed.

Comparative Production Example

The PEEK implant (self-made) having an untreated surface was prepared using the method of the comparative example.

Production Example

The surface of the PEEK implant (self-made) having the untreated surface was treated using the method of Example 6.

Experimental Example 3: Surface Characteristics of PEEK Implants

6 is a SEM image of the surface of the dental implant according to the preparation and comparative example of the present invention. Referring to FIG. 6, a large number of unnecessary burrs were observed on the surface of the polished PEEK implant in the comparative manufacturing example, while the burrs were substantially completely removed from the surface of the polished and etched PEEK implant in the manufacturing example. It became.

Experimental Example 4: Bone interface binding force of PEEK implant

20 PEEK implants according to Preparation Example and Comparative Preparation Example were implanted by applying a torque of 1 N · m to the rabbit tibia. Then, after 2 weeks (14 days) and 4 weeks (28 days), the torque required to remove the respective implants from the rabbit tibia was measured, and the average value of each was obtained and shown in FIG. 7. Referring to FIG. 7, the PEEK implant processed in the preparation example was found to provide about 40-50% higher bone interface binding force (bonding force between the implant surface and the bone formed on the implant surface) than the comparative preparation.

The foregoing description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the invention is indicated by the following claims, and it should be construed that all changes or modifications derived from the meaning and scope of the claims and their equivalents are included in the scope of the invention.

Claims (6)

In a dental implant having a surface that has been blasted and etched,
The dental implant comprises a polymer,
The arithmetic mean height Ra of the contour curve of the surface is 0.6-3.3 μm,
Dental implants with an average height (Rc) of contour curve elements of 2.6-15.0 μm. The method of claim 1,
Dental implant having an average height (Rc) of the contour curve element of 3.0 ~ 12.0μm. The method of claim 2,
Dental implant having arithmetic mean height (Ra) of the contour curve of 0.7 ~ 2.9μm. The method of claim 1,
Dental implant having an average height (Rc) of the contour curve element of 4.5 ~ 8.5μm. The method of claim 4, wherein
Dental implant having arithmetic mean height (Ra) of the contour curve of 1.1 ~ 2.5μm. The method of claim 1,
The polymer is a polyether ether ketone (PEEK), a dental implant.

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