| 摘要 |
A dental tool such as a drill, burr, anchor, reamer and the like, which is receivable in a dental tool holder, such as a dental handpiece or a hand driver, for operative positioning thereof with respect to the teeth of a patient, the dental tool having a body member provided with an operative end portion for association with the teeth and a shank extending from the operative end portion for association with the holder. The shank portion is provided with at least two cylindrical sections, each section having a circumferential groove defining a neck portion for receiving a retaining member of the tool holder for removably engaging the shank in the holder. The neck portion separates a head portion from a body portion of each section. A flat surface is formed longitudinally along one side of each section extending across the head and neck portions, and terminating along the body portion in an outwardly extending shoulder for engaging a ledge in the tool holder to thereby provide secure driving engagement between the shank and the tool holder. The cylindrical sections are spaced along the shank and provide a series of locations for driving and latching the shank in the tool holder. A circumferential notch is provided in the shank between each of the sections to permit severence of one section from the remaining sections along the shank, to thereby reduce the length of the shank for insertion into the tool holder to permit convenient access to operative areas of the patient's mouth. |
