Ivory Matrix Retainer #1 is most commonly used matrix band holder for unilateral class II tooth preparations. The matrix holder has a claw at one end with two flat semicircle arms having a pointed projection at the end. On the other end of the matrix band holder, there is a screw which when tightened, brings the ends of both the claws closer to each other. Band used with this matrix has one margin slightly projected in its middle part. This projected margin is kept towards the gingiva on the side of tooth preparation. The band of suitable size is selected and encircled around the tooth. Keeping the matrix band around the tooth, the screw of the retainer is tightened so that the band perfectly fits around the tooth. After this, wedge is placed which also helps in further adaptation of the matrix band to the tooth
