Endosseous dental implant

1. An endosseous dental implant comprising:

a body portion having a top surface and at least part of its external surface threaded, and an internal shaft or cavity comprising (a) an interlock chamber comprising two parts, a first part including a plurality of lobes extending distally from a plane at or near the top surface of said implant, said lobes protruding a first maximum radial distance into the internal sidewalls of said implant, and a second part extending distally from the distal end of said first part, said second part having the same number of lobes as said first part with each lobe starting at the base of a corresponding lobe in said first part, and extending a maximum radial distance into the internal sidewalls of said implant no greater than said first maximum radial distance, and having protrusions with a rounded, rectangular or triangular cross-sectional profile, and (b) an internally-threaded portion, contiguous to said interlock chamber, said internal shaft or cavity beginning at an opening in the top surface of said implant and ending inside said body portion.

2. The endosseous dental implant of claim 1 wherein said body portion is externally threaded over substantially its entire length.

3. The endosseous dental implant of claim 1 or claim 2 wherein said external surface of said body portion is partly threaded and, at or near the top of said dental implant, is unthreaded.

4. The endosseous dental implant of claim 3 wherein the body of said implant is tapered, and said second part has a maximum diameter smaller than the maximum diameter of said first part.

5. The endosseous dental implant of claim 1 or claim 2 wherein said internal shaft or cavity extends downwardly into said body portion from said opening at the top surface of said dental implant.

6. The endosseous dental implant of claim 5 wherein the body of said implant is tapered, and said second part has a maximum diameter smaller than the maximum diameter of said first part.

7. The endosseous dental implant of claim 2 wherein the body of said implant is tapered, and said second part has a maximum diameter smaller than the maximum diameter of said first part.

8. The endosseous dental implant of claim 1 further comprising a non-circular chamfer or bevel formed partly or entirely around said opening.

9. The endosseous dental implant of claim 8 wherein the body of said implant is tapered, and said second part has a maximum diameter smaller than the maximum diameter of said first part.

10. The endosseous dental implant of claim 1 further comprising a non-circular bevel or chamfer formed at the junction of the top surface of said implant and the tri-lobed surfaces.

11. The endosseous dental implant of claim 10 wherein the body of said implant is tapered, and said second part has a maximum diameter smaller than the maximum diameter of said first part.

12. The endosseous dental implant of claim 1 wherein said interlock chamber, in said first part, comprises three lobes spaced equally apart, and in said second part, comprises three lobes, slots or grooves of smaller maximum diameter than the lobes in said first part.

13. The endosseous dental implant of claim 12 wherein the body of said implant is tapered, and said second part has a maximum diameter smaller than the maximum diameter of said first part.

14. A two-piece abutment for use with the endosseous dental implant of claim 1 including a two-part interlock chamber comprising, in a first part, protrusions that can engage the lobes in the first part of said interlock chamber and in a second part, protrusions that can engage the lobes, rests or grooves in the second part of said interlock chamber.

15. The endosseous dental implant of claim 1 wherein the body of said implant is tapered, and said second part has a maximum diameter smaller than the maximum diameter of said first part.