Roy T Hawkinson

US Patent:

59512873, Sep 14, 1999

Filed:

Apr 15, 1998

Appl. No.:

9/060772

Inventors:

Roy T. Hawkinson - Bloomfield Hills MI

International Classification:

A61C 800

US Classification:

433173

Abstract:

Dental implant system, method and apparatus of the type wherein an implant fixture is configured at least at a distal end thereof for implanted anchoring in a jawbone of a patient and has an internally threaded bore axially disposed therein and opening centrally through a gingival end of the fixture. A threaded fastening member having a distal end portion, an axially opposite gingival end portion and an externally threaded shank portion located axially between the end portions is removably threadably engaged in the internal threads of the fixture bore. A retrieval passageway extends axially in the fastening member and opens at axially opposite ends in the respective end portions of the fastening member. The passageway has a uniform cross sectional configuration throughout its axial extent in at least the fastener distal end portion whereby an in situ fractured distal end portion segment of the fastening member, when remaining in the fixture bore after removal of the associated gingival end portion fractured fastener segment from the fixture bore, can be retrieved by inserting the working end of a specially related retrieval tool into the access opening formed by the retrieval passageway intersecting the fracture surface of the distal end portion segment to thereby unscrew and thus retrieve the distal end portion segment from the fixture bore. Various improved embodiments of such retrieval tool and implant fastening screw are also disclosed.