| 摘要 |
The invention relates to a matrix tightener (1) for dental purposes having a threaded rod (3) which can be displaced by screwing on a frame (2), slidingly displaces along the frame (2) with its front end (4) a sliding block (5) which detachably retains the ends (53, 54) of the matrix strip (18) which engages through a guide slot (15, 16) to a loop (17) which is adjustable in its width, and with its rear end (21), provided with an external thread (22), passes through an aperture (24) with an appropriate internal thread (25) of a screwing element (23) retained on the frame (2) and is provided, behind the latter, with a knurled handle (33). …<??>The object of the invention is to provide a matrix tightener of the type mentioned initially which is ergonomically simple to handle and guarantees the narrowing and widening of the loop of the matrix strip which is laid around the tooth to be treated in a fraction of the time taken by known matrix tighteners. …<??>This object is essentially achieved in that the screw element is designed as a fast-tightening nut (23) which can be tilted relative to the longitudinal axis (40) of the threaded rod (3) and is subjected to the action of a clamping spring (26) which retains it in a clamped position relative to the threaded rod (3). …<IMAGE>… |
