DENTAL IMPLANT SYSTEM

Abstract

A dental implant system includes an anchoring part of a ceramic material for anchoring in bone tissue, an abutment of ceramic material, and an abutment screw. The anchoring part has a recess that is open towards a coronal end for engagement of a fastening post of the abutment. The abutment has an opening that is continuous in the axial direction and into which the abutment screw can be inserted. The abutment screw is configured, for a fastening of the abutment to the anchoring part, to engage into an inner thread that is formed on the anchoring part in the recess or is present on an insert element that is inserted into the recess. The abutment screw has a screw head, and a shoulder, which is formed coronally and which together with the screw head forms a stop on inserting the screw into the opening, is present in the opening.

Claims

1. A dental implant system, comprising: an anchoring part for the anchoring in the bone tissue, wherein the anchoring part is manufactured of a ceramic material and defines an axis, an abutment of a ceramic material, wherein the anchoring part comprises a recess which is open towards a coronal end, for a fastening post of an abutment to engage, and an abutment screw, wherein the abutment comprises an opening being continuous in the axial direction and being shaped for an abutment screw to be inserted, wherein the abutment screw is configured, for a fastening of the abutment to the anchoring part, to engage into an inner thread which is formed on the anchoring part in the recess or is present on an insert element which is inserted into the recess, wherein the abutment screw comprises a screw head, and wherein a shoulder which is formed coronally and which together with the screw head forms a stop on inserting the screw into the opening is present in the opening, wherein the screw head and the shoulder interact such that a rotating-in of the screw up to the stop results in a wedging connection between the shoulder and the screw head.

2. The system according to claim 1, wherein the wedging connection is effected by way of an abutting of a peripheral edge of the abutment or of the screw head on a fillet-like or conical transition region of the screw head or of the abutment, respectively.

3. The system according to claim 1, wherein a fillet which has a concave curvature in the longitudinal section and which on pressing the screw against the stop is pressed against a peripheral edge of the shoulder is formed between the screw head and a screw shank which is arranged apically of this screw head.

4. The system according to claim 1, wherein the wedging connection is effected by way of a jamming of the screw head with the abutment.

5. The system according to claim 4, wherein the abutment forms a peripheral edge and a normal to the surface of the abutment screw at the location of contact to the edge has an angle of at least 30 to the axis.

6. The system according to claim 1, wherein the abutment screw is manufactured from a ceramic material.

7. The system according to claim 1, wherein the anchoring part comprises an outer thread whose thread axis corresponds to the axis.

8. The system according to claim 1, wherein the recess forms a conical support region, into which a conical support portion of the abutment engages.

9. The system according to claim 1, wherein the recess comprises an inner structure region with an inner structure which forms an insertion geometry for interacting with a corresponding rotation lock structure of the abutment.

10. The system according to claim 8, wherein the recess from coronally to apically firstly forms the support region, then the inner structure region and then an inner threaded region.

11. The system according to claim 9, further comprising an insertion tool with an engagement portion which comprises an outer structure which is adapted for engagement into the inner structure.

12. The system according to claim 1, wherein the anchoring part is designed as a bone-level anchoring part.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The subject-matter of the invention is hereinafter represented by way of preferred embodiment examples which are represented in the accompanying drawings. In part, scales which are different from figure to figure are shown:

[0046] FIG. 1 an implant system with an anchoring part, abutment, abutment screw and screw tool, in a front elevation;

[0047] FIG. 2 a sectioned representation (sectioned parallel to the axis) of the system according to FIG. 1;

[0048] FIG. 3 a representation according to FIG. 2 of the system during the putting-together;

[0049] FIG. 4 a variant of the implant system, without a screwing tool;

[0050] FIG. 5 a sectioned representation according to FIG. 4;

[0051] FIG. 6 a view of the put-together implant system of FIGS. 4 and 5;

[0052] FIG. 7 a sectioned representation according to FIG. 6; and

[0053] FIG. 8 a detail of FIG. 7

DETAILED DESCRIPTION OF THE INVENTION

[0054] In the figures, the same reference numerals indicate equal or analogous parts.

[0055] The dental implant (anchoring part 1), which, for example, is represented in FIGS. 1-3, includes an outer thread 11 that extends over almost the entire length, almost up to the coronal end, and defines an axis 100. The anchoring part 1 has an apically slightly tapering shape, so that in cross section along a plane parallel to the axis 100 as a whole it is slightly convexly curved with the exception of thread deepenings and apical clamping grooves 12 and as a whole merges continuously from a coronally roughly cylindrical into an apically tapering shape. The outer thread 11 has a non-constant thread depth and is designed, for example, in a self-tapping manner.

[0056] A recess 13, into which a fastening post 21 of an abutment 2 projects in the completed, implanted state, is open towards the coronal end. The recess forms a coronal support region 18, apically of this an insertion geometry region 19 and apically of this an inner thread region 17. The support region 18 as a whole has a conical course with a coronally slightly widening diameter. In the insertion geometry region 19, the recess forms an insertion geometry by way of it not running rotationally symmetrically about the axis 100. In the represented embodiment example, an equilateral hexagon with rounded corners is formed in the cross section along a plane perpendicular to the axis, wherein it is cylindrical in the sense that it has a constant cross section along the axis. The inner threaded region is provided with an inner thread that is matched to a screw thread of the abutment screw.

[0057] In the represented embodiment example, the anchoring part is a bone-level implant, concerning which the implant shoulder 10 with a circular edge which terminates the inner connection between the anchoring part 1 and the abutment 2 is at bone-level. The invention however can also be applied to other two-part implant systems, specifically to tissue-level implants, concerning which, for example, a transgingival region that is widened, for example, in a tulip-like manner, is formed on the anchoring part coronally of the enossal part with the thread.

[0058] Apart from the fastening post 21, the abutment 2 includes a coronal post 23 for fastening a superstructure. A transgingival region 22, which is adapted, for example, to the expected course of the gingiva, is formed apically of this. The shapes of such a transgingival region 22 as well as of the post 23here drawn with an optional flatteningincluding its angle to the fastening post and therefore to the axis 100 are adapted to the specific requirements and depending on where the implant is placed or has been placed in the jaw. In particular, an implantation set with at least one anchoring part can include several different abutments for different implantation situations.

[0059] A support portion 26, which in its shape is matched to the support region 18, is formed on the fastening post 21, and a rotation lock structure 27 is formed apically of this. The rotation lock structure has a hexagonal shape, likewise with rounded edges.

[0060] The abutment includes an axially continuous opening 29 for the abutment screw. This further forms a shoulder 24 for the head of the abutment screw. Furthermore, an optional abutment inner thread 25 for a so-called retrieval tool (a tool for removing the abutment) is present at the opening.

[0061] The abutment screw 3 has a shank region with the outer thread 33 that is matched to the inner thread of the anchoring part, as well as a screw head 31, which forms a screw stop 32 in the apical direction. A coronally open recess with an engagement structure 34, designed here in the shape in an internal hex, for a screwdriver 4, is formed in the screw head. The screwdriver 4 accordingly includes an engagement portion, in the represented example, with a hexagonal structure. In embodiments, the engaging structure and the engagement portion taper slightly apically, i.e. are shaped in a slightly conical manner, so that the screwdriver easily wedges with the abutment screw given a slight pushing-in and therefore holds this on the screwdriver. Coronally, the screwdriver includes an adapter head 41, for example for a ratchet with an adjustable torque.

[0062] FIG. 3 shows the implant system during the procedure of the abutment fastening, before the application of the superstructure (tertiary structure). The thread 33 of the abutment screw 3 is received apically by the respective inner thread of the anchoring part 1. The abutment screw 3 fixes the abutment 2 relative to the anchoring part with regard to a pulling-apart in the axial direction. Herein, the abutment is supported and guided in the support region by way of the support portion 26 bearing extensively on the inner surface of the recess there. The abutment is secured in this position with respect to rotations, by way of the rotation lock structure 27 engaging into the coronal region of the insertion geometry.

[0063] FIGS. 4-7 show the dental implant system without the screwdriver 4 and with a slightly modified abutment screw, which differs from the abutment screw of the embodiment of FIGS. 1-3, amongst other things in that the engaging structure is formed by a screw slot 35.

[0064] Furthermore, in FIG. 4 the abutment is drawn with a bevelling in the region of the coronal post 23. Generally, as is also known from the state of the art, it is particularly the coronal post of the abutment, which can be selected according to requirements and the implant situation, by which means coronal posts, which are angled to the axis, can also occur. The continuous opening howeveras is known per sewill always run axially, even given an angled coronal post.

[0065] The acting principle of the wedging mechanism according to the invention can be seen particularly well in FIG. 8, which represents a detail VIII of FIG. 7 in an enlarged manner.

[0066] The shoulder 24, which is formed on the abutment in the continuous axial opening 29 ends at the inner side in an edge 28. In the put-together condition, a fillet 38 of the abutment screw 3 is pressed against this edge. By way of this, the screw cants relative to the abutment and cannot be rotated any further apically. The axial position of the fillet 38 is selected such that this forms a stop for the screw. On account of this procedure, it is ensured that a rotating-in of the screw beyond the stop is prevented by way of this canting and the wedging effect, which is produced by this. In comparison to the state of the art with a conventional abutting of an apically facing contact surface of the screw head on a shoulder of the abutment, this has the advantage that on tightening the screw against the abutment, no significant stresses can be produced in the screw in the axial direction.

[0067] The edge 28 is drawn in an idealised manner as a sharp edge in FIG. 8. In practice, the edge 28 can also be slightly rounded. However, what can be important for the wedging is that a radius of a possible such rounding (in the longitudinal section) is smaller than the radius (in the longitudinal section) of the fillet 38, whereby a line-like contact results.

[0068] Furthermore, it is preferably the case that a peripheral line, along which an abutting of the fillet on the edge takes place, is still effected within the fillet, i.e. within that region, at which the screw is concavely rounded in cross section. By way of this, there also results the advantage of this line not having to be precisely defined on the screw itself, i.e. the procedure is also advantageous with regard to manufacturing tolerances.

[0069] A normal N to the surface of the abutment screw at the location of contact with the abutment generally has a comparatively large angle to the axis, for example at least 30 or at least 45 or even at least 55. In particular, the normal is neither parallel nor approximately parallel to the axis. An auxiliary line 101 is drawn parallel to the axis in FIG. 8 in order to illustrate the angle . This possible condition for the angle of the normal is also valid if a conical portion is present instead of a fillet.

[0070] In the described embodiments, the abutment screw engages into the inner thread 17, which is directly present in the anchoring part. However, the principle of the present invention could also be transferable to a system, concerning which the thread is formed by a separate insert element that is inserted into the recess, as is taught in EP 2 878 280 or in WO 2017/096494.