Evaluation of marginal and internal adaptation of endocrowns fabricated using conventional and digital techniques

Endocrowns are a good choice among the treatment options that can be applied in the restoration of root canal treated teeth with excessive material loss. For successful endocrown restorations, high marginal and internal compatibility is required. With the development of technology, the tendency towards digital methods is increasing. In this study, it is aimed to compare the marginal and internal fit of endocrowns fabricated by CAD-CAM and heat-pressure technique with lithium disilicate ceramic blocks using conventional and digital impression methods. After root canal treatment of the lower first molars (n=40), endocrown preparations were done and the teeth were divided into 4 groups (n=10). In the first group, conventional impressions and manual wax patterns obtained, and endocrowns were produced by heat-pressure technique (CON), in the second group digital impression were taken and wax patterns milled from CAD-CAM wax discs, endocrowns were produced by heat-pressure technique (DCD), in the third group digital impressions were taken and endocrown resin patterns obtained by using 3D printer, heat-pressure technique (D3D) were used for endocrown fabrication, in the fourth group, digital impressions were taken and endocrowns milled by using CAD-CAM (DC). Silicone replicas of all restorations were obtained, marginal and internal gaps of the replicas were measured using a stereomicroscope. Statistical analysis was performed. The highest marginal fit was observed in the group D3D, which digital impression, 3D printed resin pattern and heat-pressed technique were used. The highest internal fit was observed in the group DCD, which digital impression, CAD-CAM milled wax patterns, and heat-pressure technique were used. The marginal and internal fit of all samples obtained were found to be within clinically acceptable limits. A higher marginal fit was obtained in endocrowns obtained with the digital impression technique.