Marginal and Internal Fit of Anterior CAD/CAM Nanoceramic Composite Endocrowns with Different Preparation Designs

Abstract

OBJECTIVES: The objective of the study was to evaluate the marginal and internal fit of anterior nano-ceramic composite endocrowns with different preparation designs. METHODS: 28 extracted upper anterior teeth were selected and divided into 2 groups (n=14), group A: prepared with short extension (2 mm) and group B with long extension (5 mm). The two groups were further divided into another 2 subgroups; subgroup 1: with 2 mm ferrule while subgroup 2: without ferrule. Endocrowns were fabricated using Cerec CAD/CAM system (Dentsply Sirona, Germany) and the material for endocrowns fabrication was Lava ultimate blocks (3M ESPE, Germany). The internal and marginal fit were then measured using replica technique. General Linear Model (GLM) procedure was used for testing the significance of the main effects; (ferrule effect, endocrown extension) and their interaction, on the internal and marginal fit. (ANOVA with two fixed effects). RESULTS: 1- Marginal fit: the mean marginal replica thickness ranged from (22.05 µm) for group A1 to (36.42 µm) for group A2 with no significant effect of both ferrule and extension on marginal adaptation. P>0.05. 2-internal fit: The mean replica thickness ranged from (41.52 µm) for group A1 to (75.68 µm) for group A2. With high significant effect of ferrule P0.05. CONCLUSION: the ferrule significantly improved the internal fit of CAD/CAM nano-ceramic composite anterior endocrown, but it had no significant effect on the marginal fit. The extension of endocrown did not affect neither internal nor marginal fit.