Influence of finish-line form on crown cementation

Studies reporting the influence of finish-line configuration on the fit of cemented crowns have had conflicting conclusions. This study examined the effect of finish-line configuration on the fit of cemented complete crowns. Three identical tooth preparations were made, each with a different facial finish line: shoulder, shoulder-bevel, and chamber. The prepared teeth were replicated to produce 45 epoxy resin teeth, 15 for each finish-line design. Thirty cast crowns were fabricated and seated on their respective epoxy resin teeth--fifteen without cement and fifteen with zinc phosphate cement. An additional set of fifteen castings, seated on their working dies, was used for control measurements. All specimens were embedded, sectioned, and measured at predetermined sites. Results showed that finish-line form does not affect the fit of cemented crowns.