Evaluation of marginal and internal fit of single crowns manufactured with an analog workflow and three CAD-CAM systems: A prospective clinical study

• Published in: Journal of prosthodontics 2023-10, Vol.32 (8), p.689-696
• Main Authors: Sanchez-Lara, Alejandro, Hosney, Sherif, Lampraki, Evangelina, Conejo, Julian, Blatz, Markus B, Barmak, Abdul Basir, Ercoli, Carlo, Chochlidakis, Konstantinos
• Format: Article
• Language: English
• Subjects: Kruskal-Wallis test; Lithium; Statistical analysis
• ISSN: 1059-941X; 1532-849X
• DOI: 10.1111/jopr.13675

This prospective clinical study evaluated and compared the marginal and internal fit of crowns fabricated with an analog workflow and three different computer-aided design and computer-aided manufacturing (CAD-CAM) systems. Twenty-five participants in need of a single complete-coverage molar or premolar crown were recruited in the study. Twenty-two completed the study, and three participants dropped out. Teeth were prepared according to a standardized protocol by one operator. For each participant, one final impression was made with polyether material (PP) and three intraoral scanners: CEREC Omnicam (C), Planmeca Planscan (PM), and True Definition (TR). For the PP group, crowns were fabricated with a pressable lithium disilicate ceramic, whereas for the other three groups (C, PM, and TR), crowns were designed and milled with dedicated CAD-CAM systems and materials. Marginal (vertical and horizontal) and internal discrepancies between the crowns and tooth preparation were measured at various locations with digital superimposition software. Data was analyzed for normality with Kolmogorov-Smirnov and Shapiro-Wilk tests and then compared with one-way ANOVA and Kruskal-Wallis tests. Mean vertical marginal gap values were 92.18 ± 141.41 μm (PP), 150.12 ± 138.06 μm (C), 129.07 ± 109.96 μm (PM), and 135.09 ± 112.03 μm (TR). PP group had statistically significantly smaller vertical marginal discrepancy (p = 0.001) than all other groups, whereas no significant difference was detected among the three CAD-CAM systems (C, PM, and TR). Horizontal marginal discrepancies were 104.93 ± 111.96 μm (PP), 89.49 ± 119.66 μm (C), 113.36 ± 128.49 μm (PM), and 136.39 ± 142.52 μm (TR). A significant difference was detected only between C and TR (p