DE102006033547A1 - implant - Google Patents

Abstract

The invention relates to the production of an implant for a human or animal body by providing a green body (20), after which a molded body (30) is formed out of the green body (20), then an outer surface of the body intended for contact with the bone Etched body (30) is etched and the etched molded body (30) is subjected to a heat treatment.

Description

The The invention relates to a method for producing an implant and an implant made by this method.

It is known in the art, artificially manufactured implants to implant in the bones of a human or animal. implants Especially in the field of dentures in humans are often used. The problem is the compatibility of the implant with the bone and a swift and sufficiently stable Osseointegration.

In the DE 69 53 348 T2 the problem of biocompatibility of a dental implant with the living jawbone is described. There, an oxide layer is removed from the surface of a titanium implant, for example by immersing the implant in hydrofluoric acid. Further treatment of the surface by sulfuric acid or hydrofluoric acid produces a rough surface topography required for ingrowth. The surface of the titanium implant oxidizes and makes it biocompatible. Titan is dark.

Furthermore, dental implants made of zirconium oxide are known in the prior art. In the DE 195 37 043 A1 a dental retention pin is described which consists of zirconia. To improve the connection between Zirkonoxidstift and tooth as well as for better handling, the pin is covered with a structurable ceramic easily.

In the DE 43 32 082 A1 discloses a dental implant, which has a bioactive ceramic layer to increase the compatibility with the jawbone.

From the DE 20 2004 020338 U1 Also, a dental implant is known, wherein a molded part is machined from a Zirkonoxidgrünling that has an excess to compensate for a shrinkage due to sintering. The milled green body is then blasted with sand and only then is the fired green body sintered. The blast treatment of the surface of the zirconia green sheet creates a rough structure that increases the degree of osseointegration.

Also in the DE 10 2004 027959 A1 a dental implant is described with a zirconium oxide-based anchoring section, wherein the endosseous parts are roughened by means of blasting sand.

It The object of the invention is a method for producing an implant and an implant available which is prepared on the basis of zirconia and is and that grows fast in the bone.

Regarding The method is the object by a method with the features of claim 1.

Under Implants are used here for implant types such as bone implants, Vertebral implants, but especially understood dental implants. The implant is intended for growth on a bone. The implant can also replace bone parts.

First, will a green plant zirconia-based, preferably in rod form provided. The zirconia greenling is preferably slightly pre-sintered to give it adequate stability and toughness to rent. The greenbody can even exclusively consist of zirconium oxide.

advantageously, is zirconium oxide over titanium metal-free and in pure condition snow-white. The Zirkonoxidgrünling can Be colored in any given tooth color to be an aesthetic to achieve an appealing result. In particular, no foreign material, about a biocompatible ceramic layer to be applied, the already during of the manufacturing process influences the quality of the basic material. Also, a resorption of calcium, phosphate or composites between different materials does not occur.

Out the Zirkonoxidgrünling becomes a shaped body by preferably milling developed. Preferably, the shaped body from the zirconia body by means of a milling machine out milled. At the milling receives the greenling his fundamental geometric shape and it creates the shaped body. Milling processes are the state of the art Technology adequate known and will therefore not be described here. The molded body has an excess of about 30% to account for shrinkage due to subsequent heating wear. After the production of the green body at least one for contact with the bone certain outer surface of the green compact with acid etched. This requires milling and etching not to follow one another directly. At the etched areas receives the outer surface of the Implants an osseointegration-improving microstructure in the μ-range, the next to the shortening the healing time also increases the bone quality.

According to the invention, the etched molding is then subjected to a heat treatment. The heat treatment may preferably be a known sintering process in which the etched molding is baked in an oven at 1500 ° C to preferably 2000 ° C. Also due to the high sintering temperature acid residues are full constantly removed. The microstructure is permanently strengthened by sintering.

essential to the invention in the described method, the process steps are milling, acid treatment and subsequent sintering. It can still intermediate steps inserted become. The only slightly pre-sintered green compact is sufficiently chemical active to acid to be vulnerable to the formation of the microstructure. After the sintering process would be that Implant, in particular the outer surface of the Implants, no longer chemically active, leaving a subsequent acid treatment would not succeed.

At best, will the outside surface of the Implants with acid, preferably with concentrated hydrofluoric acid (HF), about 15 seconds treated long. For this purpose, the implant can be dipped in an acid bath and rapidly after 15 seconds to be pulled out again. The acid treatment produced on the surface of the molding the microstructure, that is a roughness in the μ-range.

The Micro roughness or microstructure is preferably less than 1 μ and is thus particularly well suited to the preparation of osteoplast cells to stimulate rapid growth of the cells to the zirconia to reach. On the other hand, the macro roughness is after the preparation of the cells especially for a fast and stable Osseointegration suitable.

By a, in a preferred embodiment of the invention the mill subsequent, but even before the acid treatment applied blasting process step receives the surface of molding a macrostructure. In the process, the surface is blasted with blasting sand granulation irradiated under certain pressure. Preferably, as blasting sand Corundum used with a particle size of 250 microns to 350 microns. The macrostructure is a roughness in the range of about 100 microns. The bone grows while healing into the macrostructure and placing the implant stuck to the bone. The bone is needed the macrostructure for integration.

At best, the implant wetting acid layer immediately after the etching process rinsed off with water.

Preferably is in a subsequent step, the acid-treated and washed molded body under Ultrasound dipped in an alcohol bath. This will, as far as one Blast cleaning was done, removed corundum residues and the surface tension the liquid reduced in the green, so that the evaporation pressure during the Drying is reduced.

To the alcohol treatment, the molding can be dried. At best, the drying takes place at 50 ° C under red light or in a drying oven for at least 30 minutes.

The described implants can be different kind. The inventive method is suitable for Production of various implants. It can, for example, vertebral implants with the method according to the invention getting produced. To remedy disc damage can an area of the two vertebrae adjacent to the defective disc be removed and replaced with a spinal implant. The implant surfaces intended for contact with the vertebral bones become with the method according to the invention treated. The vertebral implant grows faster and tighter on the two vertebrae than conventional implants.

In a preferred embodiment of the method according to the invention a dental implant is made. The dental implant has one Anchoring section and a construction section. The anchoring section and the mounting portion are preferably integrally formed of a material Made of zirconium oxide. At best, the material can only zirconia exhibit. The molded body of the dental implant is milled from the Zirkonoxidgrünling and then further treated its surface.

Of the Anchoring portion of the dental implant preferably comprises a already formed in the milling step Thread. The thread leaves turn into the jawbone, and it ensures a sufficient initial stability of the implant in the jawbone. The jawbone grows during the Healing phase in the grooves of the thread inside. It is formed thus Hintergreifungen, which is a mechanically stable connection between the dental implant and the jawbone.

It However, other anchoring structures are conceivable. Especially in the preparation of the vertebral implants, the moldings hook u. A. which are einpflanzbar in the residual bone.

Fine, usually on the anchoring portion of the dental implant formed anchoring structures of the implant outer surface, such as the thread, at best with the fine grain size of 250 microns and coarse topographies, such as smooth outer surfaces of vertebral implants or smooth anchoring structures of dental implants, with the coarse 350 μ Grain blasted. Only the areas in which the bone is to grow in need to be blasted. The construction section of the dental implant needs not to be irradiated because it is intended for attachment of the prosthetics.

By the combination of, by on on a Zirkonoxidgrundkörper after This method of formed macro and microstructure, the Optimal osseointegration.

The Task is with respect to the product by an implant with the features of claim 12 solved. The implant has in the Substantial zirconia, whose, for contact with the bone certain outer surfaces one Macro and have a microstructure.

The the external surface of the implant intended for contact with the bone is also a microstructure, preferably provided in the range below 1 micron. The roughness generated by elevations and depressions is the Microstructure. The average distances between adjacent surveys and / or Wells are less than 1 micron. The microstructure is under the method described above Use of acid produced.

At best, indicates the outer surface in addition to Microstructure one overlaying them Macrostructure, preferably in the 100 μ range, on. The macrostructure also has surveys and depressions, with adjacent ones Wells or surveys a distance of average about 100 μm to have. The macrostructure is generated by the blast treatment.

In the preferred embodiment of a dental implant, the anchoring structure may be in a root longitudinal direction aligned thread, for insertion and anchoring in the jawbone is determined. The implant points as a tooth root implant on the opposite side of the thread Side a bracket for a after healing of the implant in the jaw bone placed Crown on. Thread and bracket are through the above mill produced.

The Invention is based on an embodiment, with regard to the method and to an embodiment regarding the dental implant, described in a total of 5 figures. Showing:

1 a schematic representation of the steps of the method according to the invention,

2 a schematic side view of a dental implant according to the invention,

3 a first perspective view of a thread of the dental implant in 2 .

4 a second enlarged perspective view of the thread in 3 .

5 a third enlarged view of the thread in 3 and 4 ,

In 1 is the manufacturing method of an implant according to the invention in its application to a dental implant 10 shown. First, a zirconia green compact (ZrO ₂ ) 20 as starting material for the production of the dental implant according to the invention 10 made available. The zirconia greenling 20 is pre-sintered. The pretreatment makes the Zirkonoxidgrünling 20 stable for handling.

In a first method step A, at least a part of the zirconium oxide green body is made 20 a shaped body 30 milled. For milling, you can use known, not described in detail here milling machines and use related, conventional milling techniques. The molded body 30 after milling has already essentially the shape of the dental implant 10 with oversize to account for and compensate for the shrinkage in a later sintering step C to the final shape.

In the subsequent process step A process step B are several sub-process steps for the treatment of the molding 30 summarized.

In method step B, the anchoring section intended for contact with the jawbone is first of all 31 treated by sandblasting. The blast treatment creates a macrostructure on the surface of the dental implant 10 , which is in the range of 100 microns. Into the macrostructure 37 The jaw bone grows and anchors the dental implant 10 with it.

Depending on the area of the molding to be treated 30 a blasting sand with a different, adapted grain size can be used. Preferably, the shaped body 30 with corundum with a grain size between 250 microns to 350 microns and a pressure of 1.5 bar blasted. The small grain size of 250 μm turns into filigree structures of an anchoring section 31 , in particular for the treatment of a thread 33 used. A sandblast treatment with 250 μ grain preserves the structure of the thread 33 , On irradiation of the construction section 32 can be completely dispensed with.

Of course, it is also possible to radiate different implants, such as bone or vertebral implants, completely with a coarse grain. The molding receives its macrostructure by sandblasting 37 on the outside surface.

In the in 1 still belonging to step B subsequent substep is the green compact 30 etched with acid. This also preserves the anchoring section 31 his inventive microstructure 34 , In this case, only the anchoring section 31 acid treatment by immersing only in an acid bath. It has been found convenient to concentrate concentrated hydrofluoric acid (HF) on the blasting sand treated anchoring section for 15 seconds 31 to let act.

Subsequently, the etched anchoring section 31 quickly taken out of the acid bath and the molding 30 completely rinsed with water. This will remove most of the hydrofluoric acid.

The rinsed molding 30 is then cleaned in an alcohol bath under ultrasound. On the one hand, corundum residues are removed by the ultrasonic and alcohol treatment, and on the other hand, the surface tension of the liquid in the shaped body is removed 30 reduced. This reduces the evaporation pressure during drying.

Below, in 1 also subsumed under treatment step B, the shaped body 30 treated at 50 ° C under red light or in a drying oven for at least 30 minutes. The drying time also depends on the size of the implant.

Decisive for the abovementioned process steps subsumed under step B is the etching with hydrofluoric acid (HF). Acid treatment preserves the dental implant 10 in addition to its sandblasted macrostructure 37 , a microstructure 34 , In the microstructure 34 it is a nano roughness. The microstructure 34 is it the incorporation of the dental implant 10 in the jawbone significantly accelerates, since the first bone-forming cells due to the microstructure 34 easier to connect to the zirconia outer surface of the implant via thin fibers 10 and thus in particular the beginning of ingrowth of the implant 10 facilitate and accelerate in the jawbone.

After drying, in the process step C, the molding 30 sintered in a conventional manner. In this case, the etched molding 30 baked in an oven at about 1500 ° C. It is also possible to use sintering temperatures of up to 2000 ° C. Due to the high sintering temperature also acid residues are decomposed. By sintering shrinks the molding 30 about 30% to the dental implant 10 , in the form and size suitable for implantation. During sintering remain microstructure 34 and macrostructure 37 receive.

2 shows the dental implant 10 in its final version. The dental implant 10 has a thread 33 having anchoring section 31 and a holder 36 for the application of prosthetic elements comprehensive construction section 32 on. The anchoring section 31 is designed to taper towards the free end. He has a conical shape. The transition between anchoring section 31 and bracket 32 is as the dental implant 10 circumferential collar 35 educated.

The dental implant 10 according to 2 is implanted in the pretreated jawbone. For this purpose, the anchoring section 31 with the thread 33 screwed into the jawbone. The thread 33 gives the implant an initial stability. During healing, the jawbone grows into the macrostructure 37 , The result is a secure bond between anchoring section 31 and jawbones.

The combination of macro and microstructure 33 . 37 of the anchoring section 31 speeds healing up considerably. Without microstructure 34 would result in significantly longer healing times. Due to the microstructure 34 Fibers of bone forming cells can become faster and easier with the zirconia of the macrostructure 37 connect. Along this first forming fibers of bone forming cells, a jawbone grows into the macrostructure 37 of the dental implant 10 into it. The dental implant 10 gets its actual stability by the ingrowth of the bone into the macrostructure 37 , Bone quality is improved over conventional implants.

On the construction section 32 after healing, prosthetic elements such as stoops or crowns are cemented. After planting the anchoring section 31 In the jawbone, the wound margins can be adapted directly to the implant outer surface. The result is a soft tissue termination on the dental implant 10 , The dental implant 10 is buried, up to a few millimeters above the bone crest, in the jawbone.

3 shows the thread 33 of the anchoring section 31 in a first enlargement. The thread 33 has a diameter of about 6 mm and a length of about 10-12 mm. The pitch of the thread 33 is about 1 mm.

In 4 is the macrostructure 37 of the thread 33 in 3 shown again in a second larger magnification. 4 shows the thread 33 in a section after sintering. After sintering is the dental implant 10 Extremely strong and resistant and in this state, especially by an acid treatment, no longer changeable. In the 4 illustrated Ma krostruktur 37 is on the order of about 100 microns.

5 shows a section in 4 in a third even greater magnification. In 5 is the microstructure 34 also after sintering the thread 33 in 3 shown.

The microstructure 34 is on the order of about 0.1 to 1 μm. The microstructure 34 has small elevations and depressions. The arrangement of elevations and depressions immediately adjacent to one another forms the roughness of the microstructure 34 out. This microstructure 34 facilitates the initial attachment of the fibers of the bone-forming cells to the zirconia implant. The microstructure 34 is a nanosurface of the zirconia outer surface. The microstructure 34 is formed by etching with hydrofluoric acid in process B. By sintering, the microstructure 34 but not destroyed, but permanently and firmly trained.

10

(Tooth-) implant

20

Greenfinch

30

moldings

31

anchoring section

32

Configuration section

33

thread

34

microstructure

35

surrounding collar

36

bracket

37

macrostructure

Claims (21)

Method for producing an implant ( 10 ) for a bone of a human or animal body, comprising the steps of: a shaped body ( 30 ) is made from a green product ( 20 ) formed on a zirconia base, an intended for contact with the bone outer surface of the molding ( 30 ) is etched, and the etched molded body ( 30 ) is subjected to a heat treatment. A method according to claim 1, characterized in that the etched molded body ( 30 ) is sintered during the heat treatment. Method according to claim 2, characterized in that the shaped body ( 30 ) is sintered at about 2000 ° C. A method according to claim 1, 2 or 3, characterized in that the shaped body ( 30 ) from the green body ( 20 ) and then the outer shape of the implant ( 10 ) with an oversize. Method according to at least one of the preceding claims, characterized in that the outer surface of the shaped body ( 30 ) for generating a macrostructure ( 37 ) is blasted with blasting sand. Method according to claim 5, characterized in that that corundum is used as blasting sand. Method according to Claim 6, characterized that corundum with a grain between 250 μm up to 350 μm is used. Method according to at least one of the preceding claims, characterized in that the outer surface of the shaped body ( 30 ) is etched. Process according to Claim 8, characterized by the use of hydrofluoric acid for etching the shaped body ( 30 ). A method according to claim 8 or 9, characterized in that the etched molded body ( 30 ) is rinsed with water. A method according to claim 8, 9 or 10, characterized in that the rinsed molded body ( 30 ) is cleaned with alcohol solution in an ultrasonic bath. A method according to claim 11, characterized in that the shaped body ( 30 ) is dried afterwards. Method according to claim 1, characterized in that a shaped body ( 30 ) in the form of a dental implant ( 10 ) with an excess of the Zirkonoxidgrünling with an anchoring portion ( 31 ) and a construction section ( 32 ) is milled. Method according to claim 13, characterized in that that the excess is about 30% is. Implant for a bone of a human or animal body, produced according to at least one of the preceding claims, characterized in that the implant ( 10 ) is made of a zirconia-based material whose outer surface intended for contact with the bone is etched and has a microstructure ( 34 ) having. Implant according to claim 15, characterized in that the microstructure ( 34 ) of the outer surfaces has a macrostructure ( 37 ) is superimposed. Implant according to claim 15 or 16, characterized in that it takes the form of a dental root implant ( 10 ) has an anchoring section ( 31 ) and a construction section ( 32 ), which are integrally formed from a material based on zirconium oxide and characterized in that at least the anchoring portion ( 31 ) has on its outer surface a microstructure ( 34 ) and the construction section ( 32 ) a holder ( 36 ) for the application of a dental prosthesis. Implant according to claim 17, characterized by a thread ( 33 ) in a longitudinal direction of the anchoring portion (FIG. 31 ), which is intended for screwing into the jawbone. An implant according to claim 15, characterized in that the entire outer surface intended for contact with the bone has a microstructure ( 34 ) and / or macrostructure ( 37 ) having. Implant according to at least one of claims 15 to 19, characterized in that the microstructure ( 34 ) consists of elevations and depressions in an average distance of less than 1 micron between adjacent elevations or depressions. Implant according to at least one of claims 15 to 20, characterized in that the macrostructure ( 37 ) consists of elevations and depressions in an average distance of about 100 microns between adjacent elevations or depressions