(1) To measure the marginal and
internal adaptation of different prosthetic crowns infrastructures (IS);
(2) to analyze two types of methodologies (replica and weight
technique) used to evaluate the adaptation of indirect restorations.
Ceramic IS were fabricated using CAD/CAM technology and slip-casting technique, and metal IS were produced by casting (n=10).
For each experimental group, the adaptation was evaluated with the
replica (RT) and the weight technique (WT), using an impression material
(low viscosity silicon) to simulate the luting agent. Cross-sectional
images of the silicon replica were obtained and analyzed with Image J
software to measure the low viscosity silicon layer thickness at
pre-determined points. The silicon layer was also weighted. Results were
statistically analyzed with ANOVA and Tukey's test (α=0.05). Pearson correlation was used to analyze the relation between the two types of evaluation methods.
IS evaluated showed clinically acceptable internal and marginal
adaptation. Metal IS showed the best adaptation, irrespective of the
measuring technique (RT and WT). The IS produced by CAD–CAM showed
greater gap values at the occlusal area than at other evaluated regions.
The IS produced by the dental laboratory technician showed similar gap
values at all evaluated regions. There is no correlation between RT and
levels of adaptation were found for the different experimental groups
and for the different evaluation methods. However, all IS evaluated
showed clinically acceptable values of marginal and internal adaptation.