| 摘要 |
<p>The drill bit has a cylindrical shaft for being joined to the dental instrument and a cutting area (2) at the front. A plane segment (6) is positioned between them. The cutting segment (2), which can be cylindrical or conical, is provided with an appropriate number of main cutting edges (3) arranged in a small helix angle. Spiraled interrupting grooves (5) with trapezoidal cross sections are positioned between the main cutting edges (3) forming auxiliary cutting edges alongside.</p> |
