DENTAL IMPLANT MADE OF A METAL OR A METAL ALLOY

Abstract

Dental implant (1) for anchoring of a dental prosthesis, wherein the dental implant (1) comprises a core (10) and an external thread (3) surrounding the core (10), wherein the dental implant (1) has an apical end (11) and a cervical end (12) to be screwed by means of the external thread (3) with the apical end (11) first into a recess formed in a jaw bone and to anchor the dental prosthesis at the cervical end (12), wherein the dental implant (1) consists of material which comprises or consists of a metal or a metal alloy, wherein the core (10) has a bulge (A) in the middle area (4) in any cross-section passing through the entire length of the longitudinal axis (L) of the dental implant.

Claims

1. Dental implant (1) for anchoring of a dental prosthesis, wherein the dental implant (1) comprises a core (10) and an external thread (3) surrounding the core (10), wherein the dental implant (1) has an apical end (11) and a cervical end (12) to be screwed by means of the external thread (3) with the apical end (11) first into a recess formed in a jaw bone and to anchor the dental prosthesis at the cervical end (12), wherein the dental implant (1) consists of material which comprises or consists of a metal or a metal alloy, wherein the dental implant (1) comprises in the order from the apical end (11) to the cervical end (12) a tip area (2) in which the external thread (3) is sharp-edged, a middle area (4) adjoining the tip area (2), in which the external thread (3) is trapezoid-like and a coronal area (6) adjoining the middle area (4), in which the external thread (3) is sharp-edged, wherein a longitudinal axis (L) extends through the tip area (2), the middle area (4) and the coronal area (6), wherein the core (10) has a bulge (A) in the middle area (4) in any cross-section passing through the entire length of the longitudinal axis (L), while the external thread (3) has a nominal diameter which is constant in the entire middle area or increases in the entire middle area in a direction from the apical end (11) to the cervical end (12).

2. Dental implant (1) according to claim 1, wherein the nominal diameter of the external thread (3) is equal or increases in a direction from the apical end (11) to the cervical end (12) in an entire area comprising the tip area (2), the middle area (4) and the coronal area (6).

3. Dental implant (1) according to claim 1 or 2, wherein a thread depth in the tip area (2) and in the coronal area (6) is greater than in the middle area (4).

4. Dental implant (1) according to any one of the preceding claims, wherein the metal is titanium and the metal alloy comprises titanium.

5. Dental implant (1) according to any one of thepreceding claims, wherein an end area (8) adjoins the coronal area (6).

6. Dental implant (1) according to claim 5, wherein the end area (8) has an external or internal connection and an internal thread (9).

7. Dental implant (1) according to any one of the preceding claims, wherein the external thread (3) and the core (10) are formed in one piece.

8. Method of manufacturing of the dental implant (1) according to any one of the preceding claims by turning a turned part from a material which comprises a metal or a metal alloy, wherein the external thread (3) is cut into the turned part by means of a cutting tool, wherein the bulge (A) in the middle area (4) is created by changing of a distance of a cutting area of the cutting tool from a rotation axis coinciding with the longitudinal axis (L).

Description

[0035] Further details and features arise from the following description of an embodiment and on basis of the drawings. Therein shows:

[0036] FIG. 1 an enlarged view of an embodiment of a dental implant according to the invention,

[0037] FIG. 2 a sectional view of the dental implant according to FIG. 1 along line A-A in FIG. 1,

[0038] FIG. 3 a torque diagram of a conventional frustoconical dental implant, and

[0039] FIG. 4 a torque diagram of the dental implant according to the invention during implant insertion.

[0040] A synopsis of FIGS. 1 and 2 shows the structure of an exemplary dental implant 1 according to the invention, which comprises a core 10 and an external thread 3 surrounding the core. The dental implant has a tip area 2 which is provided with a sharp-edged external thread 3 and which may be at least slightly conical.

[0041] The tip area 2 is adjoined by a middle area 4, which is provided with a trapezoid-like external thread 3, which is more blunt than the external thread 3 of the tip area 2.

[0042] The middle area 4 is in turn adjoined by a coronal area 6, which in turn is provided with a sharp-edged external thread 3, which is thus sharper-edged than the external thread 3 in the middle area 4 and is preferably just as sharp-edged as the external thread 3 in the tip area 2.

[0043] The synopsis of FIGS. 1 and 2 illustrates that a longitudinal axis L extends through the dental implant through the tip area 2, the middle area 4 and the coronal area 6.

[0044] In addition, the sectional view of FIG. 2 illustrates that the tip area 2, the middle area 4, the coronal area 6 and an end area 8 adjoining the latter, which has an internal thread 9, form a single-piece component.

[0045] Furthermore, the sectional view of FIG. 2 shows that the middle area 4 is provided with an outward bulge A. This bulge A is illustrated in FIG. 2 by the lines L1 and L2 connecting the base areas of the external thread 3, wherein the outward direction results from the representation of the double arrow R starting from the longitudinal axis L and whose arrowheads point outward to the lines L1 and L2. In other words, this means that the bulge A results from the lines L1 and L2 being curved outward relative to a core diameter KD of the dental implant 1 in direction of an outer diameter AD of the dental implant 1.

[0046] Accordingly, the tip area 2 and the coronal area 6 are tapered compared to the bulged middle area 4, which means that these areas 2 and 6 are less massive.

[0047] A comparison of the diagrams according to FIG. 3 and according to FIG. 4 makes it clear that the courses of torque during screwing in a dental implant 1 according to the invention shown in FIG. 4 show a maximal torque range when the middle area 4 passes the cortical bone, which leads to the particular advantages of the dental implant 1 according to the invention explained at the beginning. In contrast, the courses of torque during screwing in a conventional frustoconical dental implant shown in FIG. 3 show a maximal torque range in the final phase of screwing in, when the maximal extension of the frustum is screwed into the cortical bone, thereby compressing it strongly. This is associated with the disadvantages mentioned above.

TABLE-US-00001 List of reference signs 1 Dental implant 2 Tip area 3 External thread 4 Middle area 6 Coronal area 8 End area 9 Internal thread 10 Core 11 Apical end 12 Cervical end A Bulge L Longitudinal axis L1, L2 Lines for illustration of the bulge A R Double arrow starting from the longitudinal axis L AD Outer diameter KD Core diameter