Dental instrument
US4904185A · kind A · utility
Inventor
Key dates
| Filing date | Jan 10, 1948 |
| Grant date | Feb 27, 1990 |
| Priority date | — |
| Expiry date | Jan 10, 1968 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61C5/42
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
In one embodiment, a condenser instrument for thermomechanically condensing a thermoplastic material, such as gutta percha, in the extirpated root canal of a tooth through rotation of the instrument is disclosed. The condenser instrument includes a shank having a tapered working portion along part of its length. The working portion includes a single, continuous helical flute defining a continuously helical shoulder having a negative rake angle. The shoulder is generally directed downwardly toward the tip end of the shank. A wide land is formed at the periphery of the shoulder. In a second embodiment, a remover instrument for removing a thermoplastic material, such as gutta percha, from a previously obturated root canal of a tooth through rotation of the remover instrument is disclosed. The remover instrument includes a shank having a tapered working portion along part of its length. The working portion includes a single, continuous helical flute defining a continuous helical shoulder having a negative rake angle. The shoulder is generally directed upwardly away from the tip of the shank. A wide land is formed at the periphery of the shoulder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.