| 摘要 |
A matrix band for front teeth consists of a plastic band (1) having two parts (2, 3) which extend away from each other at a preferably obtuse angle. A transition area (4) between the two parts is elastically or plastically extensible, and on each side of the transition area there is a substantially inextensible portion. A matrix retainer for a matrix band has a tightening element (6) which has a through channel dimensioned for continuous frictional engagement with two substantially inextensible portions of the matrix band which are movable face-to-face through the channel. The matrix retainer also has a locking element (7) for fixation of the two inextensible portions relative to the tightening element. <IMAGE> |
