| 摘要 |
A root canal instrument comprising a gripping end which is substantially cylindrical handgrip part, and a metallic needle part for working the tooth. An upper end of the needle-like actual working part is inserted into the gripping end either through part of the length or the entire length of the gripping end. The outer surface of the gripping end is substantially continuous, the coefficient of friction of the material used in the outer surface of the gripping end is higher than the coefficient of friction of the material typically used in gripping ends of root canal instruments made of metal, polyphenylene sulfide or a similar material. The hardness of at least the material used in the outer surface of the gripping end as well as the thickness of the material layer are so chosen that the shape of the gripping end is recoverably deformable between the fingers of the person performing the root treatment. |
