| 摘要 |
<p>There is provided a combination dental tool (40) for boring and grinding undercut bore holes in teeth. The tool (40) includes a boring end portion (42) tapering longitudinally endwardly to a minimum effective diameter at the tip and providing an axially facing cutting surface for drilling a bore into a tooth upon rotation of the tool. A shank portion extending axially from the drilling end portion (42) includes at least two successive longitudinally extending sections, the first section (46) having laterally facing cutting surfaces and a relatively larger effective diameter, and the second section (47), immediately adjacent the first section, having a relatively smaller diameter. Using this tool, an axially directed force forms the bore hole, and a laterally directed force exerted on the tool within a previously drilled bore hole, routs out an undercut portion in the internal surface of the bore.</p> |
