Filler content and gap width after luting of ceramic inlays, using the ultrasonic insertion technique and composite resin cements - An in vitro study

The effect of ultrasonic insertion on the filler content and the gap width for two brands of composite resin luting agents, intended for luting with the ultrasonic insertion technique, were studied after MOD ceramic inlays (Cerec) had been placed. In addition, the internal and marginal gap widths were determined after MOD ceramic inlays (Celay) had been luted on extracted premolars with this technique. No statistically significant differences (P>0.05) were observed for either brand between the filler content obtained from the internal surfaces, from the excess luting agent, or from the luting agent as delivered. There were no statistically significant differences (P>0.05) between the final internal and marginal gap widths when the two brands of luting agent were compared with each other. Except for the final occlusal and internal gap widths obtained for the inlays luted with the Sono-Cem luting agent, no statistically significant differences (P>0.05) were observed between the gap widths at the different locations determined. Thus, the ultrasonic insertion technique used did not significantly influence the filler ratio of the hybrid luting agents studied. Judged by the findings in this study, the properties of luting agents seem to greatly influence the final marginal and internal gap widths.