| 摘要 |
<p>A dental drill exhibits the form of a substantially solid cylindrical body (10) having a cutting portion (13) and a gripping shank (12). The cylindrical body (10) includes a boss (16) between the cutting portion (13) and the gripping shank (12). Upon the cutting portion (13), between the boss (16) and a tip (14) of the cutting portion (13), are provided at least four axi-symmetric flutes (24) upon a lateral surface of the cutting portion. Each of the flutes (24) are substantially co-axial with the longitudinal axis of the drill. The flutes (24) are separated by substantially co-axial channels (18) having radial depths of about one-eighth of the diameter of the cylindrical body (10). Each of the channels (18) flare to a larger polar dimension at the tip (14) of the cutting portion.</p> |
