DE102008037859B4 - Dental implant - Google Patents

Abstract

Dental implant (11) in the form of a composite part (27) that can be handled in one piece and consists of a fixture (12) and an abutment (13) fastened to it, characterized in that an injection-molded sintered fixture (12) and a likewise injection-molded sintered Abutment (13) are joined together by sintering or shrinking by means of a threadless longitudinal section (20) of non-circular cross-section in a blind hole (19) of non-circular cross-section, and that the abutment (13) is equipped with a connection profile (24) for later accommodation of a superstructure (14) which is designed to attach a torque tool to the abutment (13) for screwing the fixture (12) with a non-circular contour (25).

Description

The invention relates to a dental implant intended for ingrowing into a jawbone according to the preamble of claim 1.

Such a one-piece implant to be handled is in the form of a titanium fixture with a ceramic abutment of the DE 10 2005 001 185 A1 It is known that the firm, gap-free connection between the two components should prevent infection-related necrosis, which could lead to bone loss. For this gap-free connection of the abutment with the fixture, "all suitable methods" which allow an intimate connection of the materials are termed "in question". Concretely, suitable technologies for applying the annular abutment to a non-circularly tapered front end of the fixture are a layered burning, pouring, dipping or ceramic spraying, and in particular molding of an initially thermally plasticized press ceramic block. In all cases, the tapered front end of the fixture penetrates the surrounding abutment. In the lateral surface of the tapered Fixturkernes under the surrounding ceramic ring frontally open axially parallel grooves for applying a torque wrench to the fixture are incorporated. Although this mechanically relieves the abutment, the actual mechanical and thermal decoupling between the abutment-receiving superstructure and its anchoring fixture is eliminated in this implant design.

After DE 20 2006 01 844 U1 has a fixture made of zirconia ceramic a central blind hole, in which, after the ingrowth of the fixture with closed blind hole in the jaw bone, after exposing the blind hole a pin-shaped, with a central filling or venting passage through, also created from zirconia ceramic

Abutment is cemented. A later again to be removed cuff in the vicinity of the joint cross-sectional plane to prevent cement compound from leaking from the connection area in the oral cavity. Also, the trouble-free curing process of this taking place on the patient's jaw assembly process is critical.

According to the WO 2005/120386 A1 be formed on the green body of a fixture and / or one - if they are not made in one piece - in the ingrown fixture cemented later abutment, both of which are zirconia-based, prior to their final sintering in accordance with the individual operating environment in each case adapted to these roughened special sections which should promote the ingrowth in the jawbone. However, such a patient-dependent individual measure is contrary to a low-priced series production.

In recognition of these circumstances, the present invention is based on the technical problem to provide a dental implant generic type, which is less expensive and therefore cheaper to manufacture its use is easier and less stressful for the organism and its reliability and durability.

This object is achieved by the essential features specified in the main claim. Thereafter, the metallic implant fixture and its ceramic or metallic abutment are prepared separately by injection-sintering and then, before the surgical procedure, instead by screwing frictionally by Aussintern or by shrinking a longitudinal section (on the abutment or on the fixture) in a blind hole (in the fixture or in the abutment), inseparably connected with each other even in the correct angular orientation. This implant, which is thus assembled into a single composite part to be handled, is later screwed into the jawbone by attaching a torque tool above the fixture, namely to the abutment already mounted on the fixture.

This eliminates the incorporation of geometrically critical and damage-prone fine rib and thread structures in a blind hole in the connecting region of the abutment with the fixture, but also the requirement of a non-circular profile on the fixture itself for their separate screwing into a jawbone; as well as the risk of injury to the gums by the screwing tool and the double wound load by the time-spread in practice widespread screwing first the fixture in the jawbone and then only a Schraubabutments in the ingrowing fixture. On the other hand, the implant, which is completely assembled in one piece, may be loaded shortly afterwards, in special cases even immediately. As a result of the shorter duration of treatment, apart from the lower physical strain on the patient, there is also a noticeable reduction in his treatment costs.

While the fixture to be lowered into the jawbone is preferably sprayed on the basis of a titanium powder matrix, because titanium is biocompatible with the bodybone (insoluble in it and regularly without rejection reactions), the abutment protruding into the gum over the jawbone with its connection profile for the Tooth crown or bridge also on titanium powder, more advantageous to be used in color to the operating environment in the tooth gap to be adapted ceramic powder for injection molding.

It thus eliminates the manufacturing expense of growing an annular abutment on the fixture as well as the production and treatment-side effort of a conventional screw connection between fixture and abutment. For now instead preferred shrinkage of the abutment with the fixture, under engagement of a non-threaded longitudinal section (under the abutment or on the fixture) in a bare blind hole (above in the fixture or below in the abutment), the sintering process of the vicinity of the blind hole shortly before the process completion (about 90% of the desired degree of sintering) are interrupted in order to exchange a hitherto introduced into the blind hole Sinterstützkern now correct position against said longitudinal section about the same cross-sectional geometry - so that afterwards the abutment and the fixture in the course of the final sintering treatment Longitudinal section in the blind hole are forged so to speak form-fitting manner; or the already finished body (fixture or abutment) with the blind hole is heated again, whereupon the longitudinal portion of the other body (abutment or fixture) inserted into the thus slightly expanded blind hole in the correct position and then the environment is cooled again. The resulting radial shrinkage processes lead to an irreversible adhesion in the blind hole.

The solution according to the invention is therefore of particular advantage, in particular, because no blind-hole threading has to be cut into the fixture or abutment, but the casting can already take place with a blind hole which is not round in axial cross section, with a correspondingly non-circular cross section of the longitudinal section to be used here. This design promotes the transfer of the now no longer directly into the fixture but at a distance above it into the abutment introduced torque on the fixture in the one-piece screwing the fixture and abutment hermetically joined composite implant into the jawbone.

Additional refinements and modifications of the solution according to the invention will become apparent from the other claims and, with regard to the advantages thereof, from the following description of the drawings not fully scaled enlarged and limited to the functional essentials outlined preferred embodiment of the invention. The single FIGURE of the drawing shows in axial longitudinal section that of two sintered parts threadless, here positively connected to a composite part screwed into the edentulous alveolar bone dental implant for receiving a superstructure, in this example trap with engaging in the fixture abutment.

The sketched implant 11 is, preferably non-positively, of two injection-molded sintered parts to a one-piece composite part to be handled 27 put together, namely from a fixture 12 as an artificial tooth root for a lost tooth and an abutment 13 for attachment of an attached, approximately crown or bridge-shaped superstructure 14 above the fixture 12 ,

The fixture 12 has an axisymmetric, preferably non-cylindrical but from the flat end 15 to the rounded vertex area 16 tapered, as outlined approximately at an acute-conical and slightly bulged cross-section. From the outer circumferential surface 17 is at least a part of the axial length of the fixture 12 a preferably self-tapping threaded 18 , inclined relative to the longitudinal axis of the fixture, protruding like a rib.

When sketched implementation example is about coaxially in the forehead 15 the fixture a non-round blind hole 19 molded into which the abutment 13 with a longitudinal section 20 about the same non-round cross-section engages. In the context of the present invention, however, the intervention can also be realized in reverse, ie with a longitudinal section (FIG. 20 ) on the fixture 12 in a blind hole ( 19 ), with which the abutment 13 is provided. These two variants each have a longitudinal section 20 against the inner wall surface of a blind hole 19 non-positively shrink-anchored.

The abutment 13 resting with the smaller base 21 a frustoconical collar 22 , from which in the example case sketched the longitudinal section 20 protrudes, on the forehead 15 the fixture 12 , The longitudinal section 20 Coaxially protruding from the larger collar base 23 a connection profile 24 for later recording of the superstructure 14 in front. This connection profile 24 can be formed on its outer circumferential surface with a non-circular contour for applying a torque tool; sketched is instead an inner contour, for example 25 with a polygonal clear cross-section 26 for inserting a socket wrench (not shown).

The fixture 12 is a sintered injection-molded titanium-based body. The abutment 13 is also a sintered injection-molded body, also on titanium or preferably ceramic-based. Both are manufactured separately and then, preferably non-positively, to a later to be handled in one piece composite part 27 together. For this is in this example one with the blind hole 19 provided fixture 12 only finished sintered when the already finished abutment 13 with its longitudinal section 20 in the blind hole 19 is inserted, so that by means of the final sintering of the environment of the blind hole 19 the inner lateral surface of which, as it were, is cold-forged, inseparable from the outer circumferential surface of the longitudinal section inserted therein 20 is connected; or the already finished sintered environment of the blind hole 19 (here the fixture 12 ) is heated again to the blind hole 19 for axial pressing of the longitudinal section 20 widen slightly radially and then let shrink with cooling. In both cases, this will be the fixture 12 and his abutment 23 angle-oriented, torsion-resistant and inseparably frictionally engaged with one another to form an implant composite part that can then be handled in one piece 27 together.

This composite part 27 gets into the alveolar or jawbone 28 screwed in until, as outlined, its attached to the gums 29 adjacent area just above the dividing plane of the implant 11 at the forehead 15 lies. For this screwing therefore needs at the Fixtur 12 no provision for attaching a screwing tool to be taken more, causing injury to the bone 28 or gums 29 when handling the tool practically shoots out in the future. The screw connection of the implant 11 Overall, instead, now takes place by introducing a torque above the gum 29 , in the non-rotatable with the fixture 12 united abutment 13 ; and preferably at a location later from the superstructure placed over it 14 reliably closed, so that in the area of the gum 29 ultimately only smooth surfaces on the so completed dental prosthesis occur.

On the other hand, the ingrowth of the fixture 12 in the jawbone 28 , but also the threadless attachment of the longitudinal section 20 in the blind hole 19 , demanded by roughened lateral surfaces. Such surface unevenness can, with virtually no additional effort, in the manufacture of the greenware of the fixture 12 and the abutment 13 in the same powder injection molded with molded, and if necessary, then reworked in the course of sintering, be.

The in itself two-part, out into a jawbone 28 screwed fixture 12 and later into this abutment 13 existing dental implant 11 is thus according to the invention, namely preferably waiving the screw connection between Fixtur 12 and abutment 13 Although made in two parts as injection-molded sintered body but then, preferably non-positively in a shrinking process, to a single to be handled composite part 27 together. Where is the contour 25 for applying a torque tool, for screwing in the fixture 12 in the jawbone 28 , from the fixture 12 to the upper end of the abutment 13 towards, namely at its connection profile 24 for later recording of the superstructure 14 , relocated. A non-circular cross section of the in a blind hole 19 , about in the fixture 12 , engaging longitudinal section 20 , in this case the abutment 13 , promotes torque transfer from the abutment 13 to the fixture 12 when screwed into the jawbone 28 , The elimination of the second screw - namely for the previous setting of the abutment 13 only after the waxing in of the fixture 12 - reduces the cost of manufacturing the implant 11 , reduces the operation effort and relieves both the patient and his wound sites in the jawbone 28 and in the gums 29 ,

LIST OF REFERENCE NUMBERS

11

Implant (out 12 and 13 )

12

Fixtur [artificial tooth root] (from 11 )

13

Abutment [insert] (from 11 on 12 )

14

Supraconstruction [crown or bridge as a denture] (on 13 / 24 )

15

Forehead [distal end] (from 12 )

16

Vertex area (from 12 / 17 , across from 15 )

17

Outer jacket surface (from 12 )

18

Thread (on 17 )

19

Blind hole (here, for example, in 12 at 15 )

20

Longitudinal section (here, for example, on 13 under 22 in 19 )

21

small base (from 22 )

22

Collar (from 13 , above 20 )

23

larger base (from 22 )

24

Connection profile (on 22 For 14 )

25

out-of-round contour (in 13 respectively. 24 , for torque introduction in 13 / 12 )

26

Cross section (from 24 respectively. 25 )

27

Composite part ( 11 out 12 and 13 )

28

Jawbone [alveolar bone] (for taking 12 )

29

Gums ( 22 surrounding)

Claims (3)

Dental implant ( 11 ) in the form of a one-piece composite part ( 27 ) from a fixture ( 12 ) and an abutment attached to it ( 13 ), characterized in that an injection molded sintered fixture ( 12 ) and a likewise injection-molded sintered abutment ( 13 ) by means of a non-threaded longitudinal section ( 20 ) non-circular cross-section in a blind hole ( 19 ) are assembled by non-circular cross-section by sintering or shrinking, and that the abutment ( 13 ) for later recording of a superstructure ( 14 ) with a connection profile ( 24 ), which is used for attaching a torque tool to the abutment ( 13 ) for screwing the fixture ( 12 ) with a non-circular contour ( 25 ) is trained. Implant according to the preceding claim, characterized in that the connection profile ( 24 ) with a contour ( 25 ) is designed for insertion of a socket wrench. Implant according to one of the preceding claims, characterized in that the fixture ( 12 ) on the titanium base, whereas the abutment ( 13 ) is injection molded on a ceramic basis.

Images