WO1998042273A1

WO1998042273A1 - Tooth implant

Info

Publication number: WO1998042273A1
Application number: PCT/EP1998/001472
Authority: WO
Inventors: Wolfgang Dinkelacker
Original assignee: Wolfgang Dinkelacker
Priority date: 1997-03-21
Filing date: 1998-03-13
Publication date: 1998-10-01

Abstract

The invention relates to an enossal tooth implant comprising a rotationally symmetrical lower section, a head and a threaded bore hole axially extending from the head to accommodate a fastening screw to retain a crown of the tooth. The head is tapered on both sides, formed by bevels extending on both sides of the threaded bore hole across the row of teeth. The bevels form cutting lines extending from the edges of one of the front faces of the head in conjunction with the periphery of the head, said cutting lines having a variable height and matching the natural shape of the upper edge of the jaw bone. A contact member joined to the crown of the tooth is adapted to the tapering on the upper end of the head of the implant and configured to match the crown of the tooth. The two-sided tapering can be asymmetrical in design for improved matching to the anatomy of the jaw bone and the soft tissue located above. The special shape of the implant enables it to compensate for the differences in height between the tongue, the mouth and the approximate height of the bone, thereby emulating the natural upper edge of the jaw bone.

Description

DENTAL IMPLANT

Field of the invention

The invention relates to an endosseous dental implant, which has a rotationally symmetrical lower part, a head part and an axial threaded bore extending from the head part for receiving a fastening screw, which is used directly or via an intermediate member for holding a tooth crown, and which has a device for securing against Twist of the tooth crown on the head has part.

State of the art

There are known dental implants for a fixed denture, which consist of a cylindrical or conical base body, which has on its outer diameter a shape suitable for ingrowth in the jaw, such as a roughened surface, cylindrical or conical threads, step-shaped grooves and the like. The head of the implant is polished and has a central bore which is designed as a threaded hole and serves to receive a threaded bolt to which the tooth crown is attached (DE 40 28 855 C2, DE 39 17 690 C2). The tooth crown is secured against rotation by means of a device connected to the fastening, such as a square or elliptical recess. The tooth crown is supported on the implant in one plane. It is not intended to adapt the implant to the natural course of the bone. It is also known to attach a spacer sleeve between the implant head and the tooth crown, which has a circumferential shoulder on its circumference, to which the lower edge of the tooth crown adjoins (DE-A 195 09 762). The shoulder shoulder runs obliquely with a distance varying over its circumference from the upper end of the implant head, in order to achieve an improved adaptation of the transition between the tooth crown and the implant to the anatomical conditions by means of the base height of the shoulder shoulder. The spacer sleeve serves as the implant head. It is closed at the bottom and screwed into the base body of the implant by means of a thread and has a central threaded hole for receiving the threaded bolt to which the tooth crown is attached. A centering collar at the lower end of the spacer sleeve is provided with vertical projections which engage in corresponding recesses in the base body and serve to align the tooth crown and secure it against rotation.

With this device, too, the tooth crown is supported in one plane without adapting to the natural course of the bone.

Summary of the invention

The dental implant according to the invention, as defined in the claims, provides for a two-sided tapering of the head part, which is formed by bevels running on both sides of the threaded bore and transverse to the row of teeth. The bevels form cutting lines with the circumference of the head part, starting from the edge regions of an end face of the head, which run at a variable height and correspond to the course of the upper edge of the jawbone. One connected to the tooth crown The contact body is adapted to the taper at the upper end of the implant head.

The double-sided taper can be asymmetrical. For this purpose there is a flatter bevel on the lingual side of the head part and a steeper bevel on the buccal side of the head part. In this embodiment, the lines of intersection of the different bevels with the circumference of the head part run on both sides at different heights in accordance with the course of the jawbone.

The implant according to the invention allows an improved adaptation to the anatomy of the jawbone as well as the soft tissue lying above it. Due to the shape of the implant, an adaptation to the level differences between the buccal and lingual heights and the approximal height of the course of the bone is achieved and a natural upper edge of the jaw bone is simulated. Removal of bone tissue to create a uniform basis for the abutment system can be avoided and the natural course of the bone can be largely preserved and regrow when the implant heals. On the other hand, the natural course of the bone determines the natural course of the soft tissue, so that an interimplant papilla structure is formed.

The shape of the implant head, which is adapted to the level differences in the course of the bone, avoids circular inflammation. Osteolysis occurs at different levels, as is the case with normal teeth.

The arrangement also has a favorable effect on the controlled bone regeneration when using membrane technology. Cuddles through the tapered implant head the membrane follows the course of the implant head and wrinkles are avoided when the membrane is applied.

The surface of the contact body facing the tooth crown corresponds in its course to the head part and has corresponding bevels in a complementary form. The result is a simplified assembly system with integrated protection against rotation, which has improved mechanical stability in both the buccal and lingual directions. The bevels on the implant head and the corresponding bevels on the contact body absorb the lateral forces acting on the implant and prevent the occurrence of shear forces in the area of the fastening screw.

Description of the drawings

Various embodiments of the invention are described below with reference to drawings. Show it:

1 shows an embodiment of the dental implant according to the invention in a sectional view with a cutting line running along the longitudinal axis of the dental implant;

FIG. 2 shows another sectional illustration of the dental implant from FIG. 1 with a course of the cutting line offset by 90 degrees;

FIG. 3 shows a view of the implant body 1 from the lingual side; FIG. 4 shows a view of the implant body 1 from the buccal side;

FIG. 5 shows a top view of the implant head according to FIGS. 3 and 4;

Figure 6 shows a section along line A-A in Figure 2;

Figure 7 shows a section along line B-B in Figure 2;

Figure 8 is a view of the contact body 10 from direction C in Figure 2;

Figure 9 is a view of the contact body 10 from direction D in Figure 2;

Figure 10 is a view of a natural tooth arrangement;

Figure 11 is a view of a conventional implant system;

FIG. 12 shows a view of an implant system according to the invention;

Figure 13 is a partial view of the implant head of an alternative embodiment of the invention;

FIG. 14 shows a plan view of a further embodiment of the implant head according to the invention;

FIG. 15 shows a partial section of the contact body of a further embodiment of the invention; and

FIG. 16 shows a plan view of the arrangement in FIG. 15. Detailed description of the embodiment shown in Figures 1 to 9

The exemplary embodiment shown shows an endosseous tooth implant which has a cylindrical implant body 1 which consists of an implant root 2 and an implant head 3. Implant head 3 and implant root 2 can be formed in one piece, as shown in the figures, or consist of two parts which are connected to one another in a suitable manner. The implant root 2 is provided on its circumference with a thread 4 with which the implant is screwed into a predrilled hole in the jawbone. An opening 9 at the lower end of the implant root 2 is used to improve the healing of the implant in the bone. In the inserted state, the upper edge of the jawbone runs in the region of the implant head 3. As FIGS. 2 to 5 show, the implant head 3 has a bilateral taper at its upper end, which is formed by bevels 5 and 6. With this configuration, the upper end of the implant head 3 is adapted to the shape of the jaw bone.

The bevels 5 and 6 are asymmetrical. For this purpose, the bevel 5 located on the lingual side of the inserted implant runs at a flatter angle than the bevel 6 opposite it. The bevel 6 thus has a more acute angle to the longitudinal axis of the implant body 1 than the bevel 5, so that arcuate cutting lines 7 and 8 also the cylindrical circumference of the head part 3 are obtained, which run at different heights on the two sides of the implant head 3 (FIGS. 3 and 4). In this way, the the edge of the implant facing the tooth crown is largely adapted to the different course of the edge of the jawbone on the lingual and buccal side.

From the top view of FIG. 5 it can be seen that the bevels 5, 6 form straight upper edges 11, 12 with the end face 10 of the implant head. In the inserted state of the implant, the edge regions 13 and 14 of the end face 10 lie approximately at the level of the upper edge of the jawbone between adjacent teeth and thus at a different distance from the cutting lines 7, 8 forming the lower edges of the bevels 5, 6.

After the healing phase, a contact body 20 is placed on the implant head 3 and held in this position by a threaded bolt 21 which is screwed into a concentric threaded bore 19 in the implant root 2 (FIGS. 1 and 3). The contact body 20 has a guide part 22, which in the exemplary embodiment is designed as a cylinder, which engages in a corresponding recess 23 in the implant head 3. The underside of the contact body 20 is complementarily adapted to the asymmetrical shape of the implant head. For this purpose, the contact body 20 has oblique surfaces 24, 25 on both sides of the guide cylinder 22, which correspond to the bevels 5 and 6 on the implant head 3 and rest positively thereon. The surfaces 24, 25 also serve as a safeguard against axial rotation of the contact body 20 relative to the implant body 1.

The upper side of the contact body is also designed in a corresponding manner. In their angular position, inclined upper surfaces 26, 27 are the same as the inclined lower surfaces 24, 25. The outer end of the surfaces 26 terminates in a horizontal collar 28. A corresponding collar 29 is also located at the outer end of the inclined surface 27. The surfaces 24 and 26 delimit an inclined apron 30 (FIG. 8) and the surfaces 25 and 27 delimit an inclined apron 31 (FIG. 9). The aprons 30, 31 run into the cylindrical part 33 of the contact body 20 below the edge regions 13, 14 of the end face 10. The circumference of the contact body 20 increases conically upwards, the circumference 33 having a slightly concave profile. Likewise, the circumference of the contact body 20 increases upward in the region of the aprons 30, 31 with a slightly concave profile 34, 35 which merges into the circumference 33 of the contact body 20 without edges.

The contour of a tooth crown 40 adjoins the slightly concave profile 33, 34, 35 without any gaps or joints. The underside of the toothed crown 40 is adapted to the shape of the contact body 20 and is fastened thereon. An extension 36 of the contact body 20, which has a flat recess at its upper end for receiving the screw head 37 on the bolt 21, serves to align and hold the tooth crown 40. The extension 36 can have the shape of a cylinder, as shown in the drawings, or have another suitable shape such as the shape of a pointed cone. The tooth crown 40 is fastened to the contact body 20 by cementing and / or by means of a transverse screw 38 which is guided through a bore in the tooth crown and engages in a lateral threaded bore 39 in the extension 36 of the contact body 20.

The thickness of the aprons 30, 31 is such that they approximately correspond to the thickness of the soft tissue that forms on the jawbone. As a result, adaptation to the anatomical conditions is also achieved in the area of the soft tissue. The soft tissue flow is due to the natural Determines the course of the bone, to which the implant head is adapted by the bilaterally tapered design of the head part, so that an interplantary papilla structure is also formed postoperatively. FIG. 10 shows the course of the bone 41 and the course of the gums 42 and the interdental papillae 43 with a natural tooth arrangement. The corresponding view of a tooth arrangement with a conventional implant system shows the loss of the interdental papillae in the areas 44 between the implant and the neighboring natural teeth. FIG. 12 shows the implant system according to FIGS. 1 to 8 with interdental papillae 45 located between the implant 46 and the adjacent natural teeth 47, which are formed by the level adjustment to the natural course of the bone and soft tissue.

Alternative forms of implementation

Figures 13 to 16 show alternative embodiments of the invention. In the embodiment according to FIG. 13, the asymmetrical tapering of the implant head 50 is achieved at its upper end by chamfered, convexly curved partial surfaces 51 and 52, which merge into the end face 53 of the implant head without edges. The contact body (not shown) belonging to this embodiment is, as explained above, adapted to the bottom and top of the shape of the implant head 50.

It can be seen from FIG. 14 that in a further embodiment of the invention the implant head 60 has at its upper end an end face 61 with an approximately elliptical shape, which results from a convex course of the asymmetrically beveled surfaces 62 and 62 in the radial direction. In this way an adaptation to special anatomical conditions at the top of the Jaw bone possible. In this embodiment too, the associated contact body (not shown) is adapted to the bottom and top of the shape of the implant head 60.

The upper part of the contact body used to hold the tooth crown must be adapted to the axial direction of the tooth crown. FIGS. 15 and 16 show an embodiment in which an upward extension 66 of a contact body 65 is angled in the direction of a tooth crown axis 68 at an acute angle to the axis 69 of the implant body. The extension 66 is a friction body 70 which is placed on the end face 67 of the contact body 65 and is formed concentrically to the tooth crown axis 68, which is open to the axis 69 and has a bevel 71 which runs into the beveled surface 72 on the buccal side of the contact body 65. The tooth crown is fastened on the contact body 65 in the direction of the axis 68. Any other forms of upward extension of the contact body are possible.

Claims

EXPECTATIONS

An endosseous dental implant which is a rotationssymmetri ^¬ ULTRASONIC lower part (2), a head part (3) and a part originating from the head axial threaded bore (19) for receiving a fastening screw (21), directly or via an intermediate member for mounting a dental crown (40), and which has a device for securing against rotation of the tooth crown on the head part,

marked by:

(a) a double-sided taper on the head part (3), which is formed by bevels (5, 6, 62, 63) running on both sides of the threaded bore (19) and transverse to the row of teeth;

(b) an end face (10) on the head part (3), which has edge regions (13, 14) on both sides of the threaded bore (19) in the direction of the row of teeth, which define a basic level for the denture, from which the cutting lines (7, 8 ) the bevels run at a variable height with the circumference of the head part, which is adapted to the course of the jawbone,

(c) a contact body (20) which is connected to the tooth crown (40) and on its underside (24, 25) is adapted to the double-sided taper at the upper end of the head part.

2. Implant according to claim 1, characterized in

(al) that the two-sided taper on the head part (3) is asymmetrical and has bevels (5, 6, 62, 63) running at different angles to the implant axis;

(bl) that a flatter bevel (5, 62) on the

Lingual side (C) and a steeper bevel (6, 63) is provided on the buccal side (D) and that the bevels from the basic level of the end face (10), on both sides over the circumference of the head part, run at different heights (7 , 8) form; and

(cl) that the contact body (20) on its underside (24, 25) is adapted to the asymmetrical taper on the head part.

3. Implant according to claim 1, characterized in that the bevels (5, 6) are flat surfaces.

4. Implant according to claim 1, characterized in that the bevels in the axial direction convex surfaces

(51, 52) are.

5. Implant according to claim 1, characterized in that the bevels in the radial direction are convex surfaces (62, 63) which form an approximately elliptical end face (61) of the implant head (60) on their upper edges.

6. Implant according to claim 1, characterized in that the contact body (20) has a two-sided taper on its upper side, which corresponds in part to the shape of the two-sided taper of the head and to which the tooth crown (40) is adapted.

7. Implant according to claim 2, characterized in that the contact body (20) has bevels (26, 27) on its upper side which are at least approximately adapted to the asymmetrical bevels (5, 6) on the implant head (3) in their angular position.

8. Implant according to claim 7, characterized in that asymmetrical surfaces (24, 26 and 25, 27) on the underside and on the top of the contact body (20) form different inclined aprons (30, 31) and that on the buccal side of the Apron (31) located in the contact body has a more acute angle of inclination to the implant axis than the apron (30) located on the lingual side.

9. Implant according to claim 1, characterized in that the bevels (26, 27) each have a narrow collar (28, 29) running at least approximately at right angles to the implant axis at their lower edges.

10. Implant according to claim 1, characterized in that the contact body (20) has a cone-shaped to the tooth crown (40) enlarging circumferential profile (33, 34, 35) for continuous adjustment to the circumference of the tooth crown.

11. Implant according to claims 8 and 10, characterized in that the increasing circumference of the contact body (20) has a concave curvature which also extends over the circumferential region of the aprons (30, 31).

12. Implant according to claim 1, characterized in that the contact body (20) has a central bore for receiving the threaded bolt (21) and a guide part (22) which is fitted into a complementary recess (23) in the implant body (1).

13. Implant according to claim 1, characterized in that the contact body (20) has an extension (36) upwards, which serves for fastening the tooth crown.

14. Implant according to claim 13, characterized in that the extension (36) of the contact body (20) is designed as a cylinder arranged concentrically to the implant axis.

15. Implant according to claim 13, characterized in that the extension (36) of the contact body (20) is designed as a cone arranged concentrically to the implant axis.

16. The implant according to claim 13, characterized in that the extension (36) of the contact body (20) is designed to receive a transverse screw (38) for fastening the tooth crown.

17. The implant according to claim 13, characterized in that the extension (66) of the contact body (65) extends at an acute angle to the implant axis (69) which is adapted to the axial position (68) of a tooth crown placed obliquely on the implant body.

18. Implant according to claim 17, characterized in that the extension (66) of the contact body (65) as a from the end face (67) of the contact body (65) concentric to the tooth crown axis (68) projecting upward friction body (70) which is open to the implant axis (69).