Dental implant

Abstract

A dental prosthesis comprises an implant, an abutment and a crown. The implant has distal and proximal portions with the implant proximal portion including distal and proximal segments. The implant proximal segment has an outer surface. The abutment has distal and proximal segments and defines an abutment shoulder therebetween. The abutment shoulder is configured to circumferentially engage the outer surface of the implant proximal segment such that an implant abutment joint is defined therebetween. The crown is configured to be positioned over the abutment and the implant such that the crown covers the implant abutment joint. The implant proximal segment has an annular concave cross-section such that the crown distal end has a rounded shape to reduce the potential for stress cracking of the crown.

1 . A dental prosthesis, comprising:
 an implant having distal and proximal portions, the implant proximal portion including distal and proximal segments, the implant proximal segment defining an implant proximal end, the implant proximal segment having an annularly tapered outer surface extending from the implant proximal end and defining a conical shape, the annularly tapered outer surface defining a diameter that increases from a minor diameter to a major diameter as the distance from the implant proximal end increases;   an abutment having distal and proximal portions defining an abutment shoulder therebetween, the abutment proximal portion including an abutment collar, the abutment proximal portion having an annularly tapered inner surface extending into the abutment proximal portion from the abutment collar to define an abutment cavity, the abutment collar defining a diameter being less than the major diameter and greater than the minor diameter, the annularly tapered inner surface engaging the annularly tapered outer surface of the implant proximal segment with a portion of the implant being received within the abutment cavity to define an implant abutment joint therebetween; and   a crown configured to be positioned over the abutment and the implant such that the crown covers the implant abutment joint.   
   
   
       2 . The dental prosthesis of  claim 1  wherein the abutment cavity is formed complementary to the annularly tapered outer surface to facilitate circumferential engagement of the abutment shoulder to the annularly tapered outer surface. 
   
   
       3 . The dental prosthesis of  claim 2  wherein the tapered outer surface is conically shaped and having a half angle of about 45 degrees. 
   
   
       4 . The dental prosthesis of  claim 1  wherein the implant distal segment is cylindrically shaped. 
   
   
       5 . The dental prosthesis of  claim 1  wherein the implant distal segment defines a circumferential undercut between the implant distal portion and the implant proximal segment. 
   
   
       6 . The dental prosthesis of  claim 5  wherein the undercut has an arcuately shaped cross section. 
   
   
       7 . The dental prosthesis of  claim 1  wherein the abutment has an abutment neck disposed adjacent the abutment distal end, the abutment neck having a reduced cross section in an axial direction. 
   
   
       8 . The dental prosthesis of  claim 1  wherein:
 the crown includes a crown distal portion defining a crown distal end having a crown cavity formed therein;   the crown cavity being configured complementary to the abutment proximal segment such that the crown distal end circumferentially engages the implant proximal segment.   
   
   
       9 . The dental prosthesis of  claim 1  wherein:
 the receipt of the abutment proximal portion and the abutment proximal segment into the crown cavity resulting in the engagement of the crown distal portion to the outer surface of the implant proximal segment such that the crown implant joint is defined therebetween;   the implant abutment joint being covered by the crown distal portion;   a layer of adhesive being disposed between the implant proximal segment and the crown cavity at the crown implant joint.   
   
   
       10 . The dental prosthesis of  claim 1  wherein:
 implant proximal portion defines an implant proximal end having an implant aperture disposed therein;   the abutment includes abutment proximal and distal portions, the abutment distal portion being configured to be insertable into the implant aperture.   
   
   
       11 . The dental prosthesis of  claim 1  wherein the abutment proximal portion has a frusto-conical outer surface. 
   
   
       12 . The dental prosthesis of  claim 1  wherein the implant proximal segment has a concave cross section. 
   
   
       13 . The dental prosthesis of  claim 12  wherein:
 the implant proximal segment is defined by upper and lower conical surfaces;   the lower conical surface extending upwardly from the prosthetic margin and having a half angle of up to about 45 degrees;   the upper conical surface extending downwardly from the implant proximal end and having a half angle of up to about 5 degrees;   a radius being formed between the upper and lower conical surfaces.   
   
   
       14 . The dental prosthesis of  claim 13  wherein:
 the implant proximal segment has a height of about 1 millimeter (mm);   the upper conical surface intersecting the radius at a tangent thereof;   the concave cross section being configured such that the tangent is offset radially inwardly from the prosthetic margin by about 0.2 mm to about 1 mm.   
   
   
       15 . A dental prosthesis, comprising:
 an implant having distal and proximal portions, the implant proximal portion including distal and proximal segments, the implant distal segment defining a circumferential undercut between the implant distal portion and the implant proximal segment, the implant proximal segment having an implant proximal end, the implant proximal segment having an annularly tapered outer surface extending from the implant proximal end and defining a conical shape, the annularly tapered outer surface defining a diameter that increases from a minor diameter to a major diameter as the distance from the implant proximal end increases;   an abutment having abutment distal and proximal portions and defining an abutment shoulder formed therebetween, the abutment proximal portion including an abutment collar, the abutment proximal portion having an annularly tapered inner surface extending into the abutment proximal portion from the abutment collar, the abutment proximal end defining a diameter being less than the major diameter and greater than the minor diameter, the annularly tapered inner surface engaging the implant proximal end such that an implant abutment joint is defined therebetween; and   a crown configured to be positioned over the abutment and the implant such that the crown covers the implant abutment joint.   
   
   
       16 . The dental prosthesis of  claim 15  wherein the undercut has an arcuately shaped cross section. 
   
   
       17 . A dental prosthesis, comprising:
 an implant having distal and proximal portions, the implant proximal portion including distal and proximal segments, the proximal segment having a concave cross section, the implant proximal segment having an implant proximal end, the proximal segment defining a diameter that increases from a minor diameter to a major diameter as the distance from the implant proximal end increases;   an abutment having abutment distal and proximal portions and defining an abutment shoulder formed therebetween, the abutment proximal portion including an abutment collar, the abutment proximal portion having an annularly tapered inner surface extending into the abutment proximal portion from the abutment collar, the abutment proximal end defining a diameter being less than the major diameter and greater than the minor diameter, the annularly tapered inner surface engaging the implant proximal segment such that an implant abutment joint is defined therebetween; and   a crown configured to be positioned over the abutment and the implant such that the crown covers the implant abutment joint.   
   
   
       18 . The dental prosthesis of  claim 17  wherein:
 the proximal segment is defined by upper and lower conical surfaces;   the lower conical surface extending upwardly from the prosthetic margin and having a half angle of up to about 45 degrees;   the upper conical surface extending downwardly from the implant proximal end and having a half angle of up to about 5 degrees;   a radius being formed between the upper and lower conical surfaces.   
   
   
       19 . The dental prosthesis of  claim 18  wherein:
 the upper segment has a height of about 1 mm;   the upper conical surface intersecting the radius at a tangent;   the concave cross section being configured such that the tangent is offset radially inwardly from the prosthetic margin by about 0.2 mm to about 1 mm.   
   
   
       20 . The dental prosthesis of  claim 19  wherein:
 the crown includes a crown distal portion defining a crown distal end having a crown cavity formed therein   the crown cavity being configured complementary to the abutment proximal segment such that the crown distal end circumferentially engages the implant proximal segment.