Evaluation of Diverse Digital Impression Systems on the Three-Dimensional (3D) Fit of All-Ceram CAD/CAM Crowns

Abstract

Aim: This in vitro study's objective is to assess the Three-Dimensional (3D) internal and marginal fit of all-ceramic CAD/CAD crowns produced by various digital impression systems. Materials and Methods: Three different intraoral scanners: CEREC Primescan (Dentsply Sirona), Trios 4 (3Shape), and CS 3700 (Carestream Dental) were used to digitally scan an experimental model based on ISO 12836:2015. The CAD/CAM processes suggested by each system (CEREC Primescan, Trios 4 and CS 3700; N = 15) were used to create ceramic crowns. A 3D inspection program (Geomagic control X) was used to measure The Three-Dimensional (3D) marginal and internal fit of each ceramic crown. By using the Kruskal-Wallis test, differences between the systems and various measurements were assessed. Pairwise comparisons were used to validate statistically significant differences (= 0.05). Results: Occlusal gaps in the CEREC Primescan, Trios 4 and CS 3700 groups were 113.0, 161.3, and 438.2 µm, respectively (p<0.001). The axial gaps were 83.4, 78.0, and 107.9 µm, respectively. While the marginal gaps were 77.8, 99.3, and 60.6 µm, respectively, finally the whole gaps were 85.9, 107.3, and 214.0 µm, respectively. The marginal gap sizes with the Trios 4 system were considerably different from those with the other two systems. The CEREC Primescan system proved no distinctive variations between the four measured regions. However, the Trios 4 and CS 3700 systems did show a statistically significant difference (p<0.05). Conclusion: The marginal gap, which is the most essential aspect in the marginal and internal fit of fixed prostheses, was recorded to be below 100 µm in all three systems, leading to the conclusion that all three systems are capable of producing clinically acceptable prostheses.