Patent ID: 8475459

Claim:
A drill tipped shaft for use during surgery for initial longitudinal insertion into periosteum and other body material, such as cartilage and bone material, followed by rotational movement to a further depth in the body material, said drill tipped shaft comprising a shaft having: (1) an end portion defining a drill tip for creating a securing hole in the body material to prevent the end portion from slipping on periosteum and other body material as the shaft begins to rotate, said end portion having a pyramidal shaped end formed from three faces intersecting to form three first cutting edges disposed relative to one another to provide for initial longitudinal insertion of said shaft into the body material and to cut away bone material during rotation of said shaft, each of said three faces intersecting with two of the other faces so as to define two of said three first cutting edges; (2) a second portion extending rearwardly of said end portion, said second portion having a. three chamfered faces defining three second cutting edges, each of said second cutting edges extending from one of said first cutting edges; and b. three curved faces, each of said curved faces having a concave shape and intersecting with two of said chamfered faces so as to define both a said second cutting edge of one of said chamfered faces and a trailing edge of another of said chamfered faces; and (3) a third portion extending rearwardly of said second portion, said third portion having three recess surfaces for directing away debris produced during rotational movement of the shaft, each of said three recess surfaces intersecting with one of said curved faces for directing debris from one of said curved faces into said one of said recess surfaces.