Patent ID: 7665989

Claim:
A drill for use on a jaw bone with overlying soft tissue and underlying, more solid bone, comprising: a first portion disposed at a distal end of the drill, the first portion comprising a pair of first cutting edges, the first portion having a first width; and a second portion disposed at least partially intermediate the first portion and a proximal end of the drill, the second portion comprising a pair of edges extending intermediate a pair of second cutting edges and the pair of first cutting edges, the pair of second cutting edges extending at an angle relative to a longitudinal center line, the pair of edges extending from the first portion in a generally perpendicular direction relative to the longitudinal center line, the second portion having a second width that is greater than the first width, the second portion further comprising a portion having a generally cylindrical surface and at least one recess in the generally cylindrical surface thereof, the recess being formed with a wall disposed proximally relative to the pair of first cutting edges, the pair of second cutting edges, and the pair of edges of the second portion, the recess and the wall being configured to receive the soft tissue and to remove the soft tissue outwardly from the drill during drilling; wherein the first portion is configured to cooperate with the soft tissue to form an initial hole in the soft tissue, and the second portion is configured for enlargement of said initial hole and for formation of a countersink hole in the more solid bone, and wherein the first portion is also configured to cooperate with the more solid bone, during the second portion's formation of the countersink hole, in order to produce a guidance hole or marker hole in the bottom of the countersink hole.