Dental implants

A dental implant having a generally cylindrical or conical body and a bore extending distally along a longitudinal axis of the implant into the body from a proximal end of the body;

• the bore having a bore wall defining:
• a socket region,
• an internally threaded hole distal to and radially inset from a wall of the socket region, and
• an interface portion between the socket region and the internally threaded hole, said interface portion including a first section distal to said socket region and a second section contacting said internally threaded hole and being proximal thereto;
• wherein a shape of the interface portion comprises a change in angle from an orientation along said bore axis at a proximal side of the interface portion to an orientation at a distal side of the interface portion;
• wherein said interface portion has a cross-sectional profile including a curve having a plurality of portions, wherein each portion of the cross-sectional profile includes first and second ends each having an associated angular orientation of a tangent to the curve defined by the interface section of the wall at that end, relative to said implant longitudinal axis, wherein said angular orientations of the tangents to the curve at said first and second ends differ by 15° and a distance along the bore wall between said first and second ends is at least 38 μm;
• wherein the change in angle is distributed along the longitudinal axis and within a longitudinal plane containing the longitudinal axis;
• and
• wherein the extent of the distribution is sufficient to reduce stress concentration for prevention of primary stress failure at a region of wall between the socket region and the internally threaded hole.