The Dental cosmos . Matrix burnisher. edges, a double-ball instrument (Fig. 3)should be used so that it may be placedastride upon the marginal edge, and onthe gingival border the use of a flat-tened burnisher will produce the desiredresults. To remove the matrix from the cavitv it should be gently teased therefrom witha fine-pointed instrument, so as nor toaffect the shape, and then allowed todrop on the mouth-mirror which may beused to convey the matrix to the labora-tory. In these cavities the methods usedfor the retention of the inlay will de-pend upon the means used in the con-struction of
The Dental cosmos . Matrix burnisher. edges, a double-ball instrument (Fig. 3)should be used so that it may be placedastride upon the marginal edge, and onthe gingival border the use of a flat-tened burnisher will produce the desiredresults. To remove the matrix from the cavitv it should be gently teased therefrom witha fine-pointed instrument, so as nor toaffect the shape, and then allowed todrop on the mouth-mirror which may beused to convey the matrix to the labora-tory. In these cavities the methods usedfor the retention of the inlay will de-pend upon the means used in the con-struction of the shell inlay and the coun-tersunk inlay with pin attachments. In the construction of the shell inlay(Fig. 4) a core of cement is formed atthe base of the cavity and built up towithin a few lines of the marginal intervening cement will prevent thematrix from being forced to the floor Fig. 4. Fig. of the cavity, and while rendering easierthe forming of the matrix, will allow forthe attachment of pins, posts, or method for making these attach-ments is as follows: In devitalized teeth,where it is possible to make an extensiveretention for the inlay, a small tube maybe placed in an upright position (Fig. 5),and the core of cement formed around iton a level with the upper extremity ofthe tube. The matrix is placed over thecore, and a post is inserted through thefoil into the tube, extending it slightlybeyond the matrix^ The matrix and postattachment are withdrawn from the cav-ity by means of wax inserted on a cavityimpression tray. Matrix and post arenow invested in plaster, and after themass becomes thoroughly set the wax isremoved by means of hot water, afterwhich the matrix is ready for the con-touring and casting process. The postattachment will readily pass into the tubein the core. Most of rhe core shouldbe removed from the cavity in order toafford a stronger retent
Size: 1976px × 1265px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthor, bookcentury1900, bookdecade1900, booksubjectdentistry
