EFFECT OF THE ULTRASONIC INSERTION TECHNIQUE ON THE SEATING OF COMPOSITE INLAYS

The seating of MOD composite inlays was determined before and after ce mentation with one of three cements of different viscosities. The seat ing was determined by measuring the axial discrepancy. Inlays were sea ted by strong finger pressure or by the ultrasonic insertion (USI) tec hnique. The axial discrepancy of luted inlays varied between 115 mum a nd 472 mum. The axial discrepancy of inlays luted with finger pressure increased with the viscosity of the cement (Duo Cement < Twinlook < S ono-Cem). Inlays luted with the cement of lowest viscosity (Duo Cement ) had seating values of similar magnitude irrespective of seating proc edure. As compared with luting by finger pressure, use of the USI tech nique improved the seating of inlays luted with Twinlook and Sono-Cem (the cement of highest viscosity) to such an extent that the values of seating were of the same magnitude as those of inlays luted with Duo Cement. Consequently, the seatings of inlays cemented with the USI tec hnique did not depend on the viscosity of the cement.