Does Cavity Base Shade of Endocrowns Play a Role in the Accuracy of Intraoral Scans?

The aim of the present study was to evaluate the effect of composite resin shades (A1, A2, A3, B1) on the accuracy of scans performed using the Trios 3 (3Shape, Denmark) intraoral scanner.

An endocrown cavity was prepared on an extracted human molar embedded in a mandibular dentate typodont. Composite resin shades (A1, A2, A3, B1) were sequentially placed in the pulp chamber, light-cured, and scanned using the Trios 3 intraoral scanner. A high-precision extraoral scanner (E1, 3Shape, Denmark) provided reference data, and the intraoral scanner acquired test data. The composite resin shades were measured using a spectrophotometer (Easyshade, VITA, Germany) to obtain L*, a*, and b* values. Scanning data were analyzed in Geomagic Design X to calculate root mean square (RMS) values for trueness and interquartile range (IQR) for precision.

Significant differences in RMS values were found among shade groups (p < 0.001). The highest value was for B1 (0.0336 ± 0.003), and the lowest for A3 (0.0242 ± 0.002). A1 and A2 showed no significant difference, while all other comparisons were significant. The highest IQR value was observed for B1 (0.0040), indicating reduced precision.

The composite resin shade considerably influenced intraoral scanner accuracy. Darker shades are suggested for endocrown cavity bases to optimize digital impressions. Further studies are required to investigate these findings in clinical practice.

This study highlights the influence of cavity base material shade on intraoral scanner accuracy in endocrown restorations. Darker shades improved scanning accuracy, highlighting the importance of material selection in digital workflows.