Effect of cement application techniques on the adaptation and retention of provisional crowns.

Abstract

A well-made and properly cemented provisional restoration is essential for the health of abutment teeth and periodontium. Few focused studies are available on the effect of cementation techniques on the fit as well as on the retention of the provisional crowns. To investigate the effect of six cement application techniques on the adaptation and retention of provisional crowns. Seventy-two provisional crowns (Bisacryl resin) were fabricated over identical self-cured resin dies and were divided into six groups (N= 72; 6 ×n= 12) of cement application techniques (Temp Bond NE, Kerr Corporation). Group-A (Bulk Fill); Group-B (Cement on inner walls); Group-C (Cement on axial walls); Group-D (Cement on crown margin); Group-E (Cement on tooth margin); Group-F (Cement with vent-holes). Adaptation was assessed before and after cementation with digital caliper (0.001mm). Universal testing machine was used for retention measurement in Mega Pascal's (MPa). Data was analyzed by SPSS using Paired T-Test and Tukey's test (p< 0.05). The highest and lowest difference between the two measurements was observed for the Group A (0.095mm) and Group C (0.030mm) respectively. Paired T-Test revealed significance (p< 0.05) between before and after cementation. Group-F (0.6094MPa) and Group-E (0.1858MPa) showed the highest and lowest retention respectively. Group-E (Cement on tooth margin) with lowest retention significantly differed (Tukey's Test; p< 0.05) from other groups. Bulk filling of the provisional crown with luting cement significantly increases the adaptation discrepancies. Discrepancies are more when luting cement is applied on the occlusal surface of the crowns. However, it didn't influence the retention of the crowns. Cement application on axial walls and cervical third of intaglio surface of crowns was the method of choice with regards to adaptation and retention combined. Addition of vent-holes improved the adaptation with best possible retention.