Fastening structure using a taper implant

A taper implant comprising a taper portion formed to define an outer surface of said taper implant, and a projecting portion formed at an outermost end of said taper portion on the larger-diameter side to project outward with respect to said taper portion and having a flat surface lying perpendicularly to the axial direction of said taper portion.

A taper implant comprising:

• a taper portion having an outer surface being frustconical in shape,
• a flange portion formed at an outermost end of said taper portion on the larger-diameter side to project outward with respect to said taper portion, and having a flat surface lying perpendicularly to the axial direction of said taper portion, and
• a female thread portion formed to penetrate said taper portion, extending in the axial direction of said taper portion, and having an axis aligned with the axis of said taper portion.

A screw-fastening structure using a taper implant with female threads wherein a hole having a hole taper portion gradually spreading toward a larger-diameter opening is drilled in a first member, a taper implant having a taper portion including female threads tapped therein beforehand is fitted to said hole taper portion, and a male screw is inserted and tightened into said female threads from the side of a second member, whereby said first and second members are fastened to each other.

A forming drill for drilling an insertion hole for a taper implant, wherein said drill integrally includes a taper portion drilling bit for boring a hole into which a taper portion of said taper implant is to be inserted, and a step portion drilling bit for boring a hole into which a projecting portion of said taper implant is to be inserted, and a hole taper portion and a hole step portion of said hole are drilled in a member at the same time by said integral bits of said drill.