Effect of adhesive resin cement on design of partial veneer crowns

Statement of problem. Procedures involved in the tooth preparation, impress ion, and casting of partial veneer three-quarter crowns are considered to b e complex. Purpose. This study assessed whether a simplified partial veneer crown desi gn, when cemented with a 4-META adhesive resin, had a comparable resistance to displacement forces compared with a conventionally prepared partial ven eer crown cemented with a traditional luting agent. Material and methods. Conventional partial veneer crowns were prepared on 2 0 natural premolars, and 20 other premolars received modified partial venee r crown tooth preparations without proximal grooves. Artificial crowns were made for these teeth with Students alloy. Half the crowns in each of the 2 groups were luted with 4-META resin; the other half were luted with a zinc phosphate cement. Loads required to displace the partial veneer crowns wer e recorded after 24 hours and thermocycling, then the mode of separation wa s recorded for each crown. Average force required to displace partial venee r crowns for the 4 groups were subjected to 2-way analysis of variance and Scheffe test. Results. The 2 groups luted with 4-META resin and the group with proximal g rooves luted with zinc phosphate were not significantly different. However, they were all greater than the group without proximal grooves luted with z inc phosphate cement. Conclusion. Forces required to displace partial veneer crowns prepared in a traditional manner and those teeth prepared without proximal grooves were similar if the artificial crowns were luted with adhesive resin cement.