Evaluating residual dentin thickness following various mandibular anterior tooth preparations for zirconia...

The objective of this study was to evaluate the residual dentin thickness (RDT) after different tooth preparations. Ninety mandibular anterior teeth were divided into three groups: central incisors, lateral incisors, and canines. Specimens were prepared for single-crown coverage with shoulder, slight chamfer, and knife-edge finish lines. Specimens were sectioned and divided into four subgroups according to measurement areas: (1) buccal, (2) distal, (3) lingual, and (4) mesial. The RDT was analyzed statistically by means of one-way analysis of variance and Tukey post hoc test (P = .05). Significant differences were found for shoulder but not for slight chamfer and knife-edge finish lines. The interproximal areas wound up being critical due to thin RDT, potentially interfering with the structural and biologic integrity of teeth.