Marginal adaptation of cast partial crowns made of pure titanium and a gold alloy under influence of a manual burnishing technique.

Abstract

The aim of this study was to determine the marginal adaptation of partial crowns from pure titanium and a gold alloy after two different cementation techniques. Forty freshly extracted human molars were prepared and randomly divided in four groups. Two groups were restored with partial crowns using the gold alloy Degulor M*. In one group, the crowns were fixed on the tooth by using a zinc phosphate cement. In the other group the margins were additionally burnished by using a hand burnisher No. 660. In the other two groups, partial crowns from pure titanium were cemented in the same way. The marginal quality was determined by quantitative margin analysis in the SEM using a replica technique. Partial crowns from a gold alloy showed significantly (P < 0.05) more margin quality A (vertical marginal discrepancy < 50 microm) while partial crowns from pure titanium had significantly (P < 0.05) more margin quality B (vertical marginal discrepancy 50-100 microm) and over-extended margins (quality D). No significant (P < 0.05) difference was found between the conventional cementation technique and the technique with manual burnishing in both material groups.