Method of drilling through a bone structure
OwnerJohn W. Bakerinventor
Life of this patent
Estimating the term…
Abstract
A new drill-type cranial perforator is disclosed of the type which comprises a front drill head assembly made up of a leading inner drill and a trailing outer drill, and a rear support and drive assembly adapted to enable both drills so long as the leading inner drill is encountering a resistive surface and to disable both drills when the leading inner drill stops encountering the resistive surface. The leading inner drill has at least one drilling flute with a forward cutting edge including a reentrant cutting segment axially rearward from the outer end of the forward cutting edge and extending inwardly towards the longitudinal axis of the perforator.
Claims8
A method of drilling through a bone structure comprising simultaneously drilling a cylindrical hole and an annular channel cut coaxial with and at the bottom of the hole, whereby a cylindrical wafer or pillow is formed at the bottom of the hole when the thickness of the bone structure is at least partially penetrated along said annular channel, and discontinuing drilling immediately upon formation of said wafer or pillow.
Dependencies are inferred from the claim text.