In vitro evaluation of the dimensional accuracy of total single-unit provisional crowns produced by digital workflow

Abstract

Objective: This in vitro study aims to digitally analyze and compare the accuracy of single-unit provisional crowns produced through digital workflows, using both subtractive (milling) and additive (3D printing) methods. The analysis employs image overlay methods and area calculations. Material and Methods: To conduct the research, a total crown preparation was performed on a dental mannequin for tooth 26, using the silhouette technique. After scanning the preparation, a provisional single-unit crown was designed using 3D CAD software, resulting in the production of 30 crowns: 15 milled and 15 printed. All specimens were scanned and analyzed using specialized 3D image software. Measurements were focused on the internal and marginal areas of the crowns, with a total of 30 measurements for the internal area and 120 for the marginal area. The original design, projected in 3D CAD software, served as the reference. Statistical analysis, including independent samples t-tests, Shapiro-Wilk normality tests, and descriptive statistics, was applied to all collected data. Results: Regarding the internal area, there was a statistically significant difference when comparing groups P (printed) and M (milled). Group P showed higher discrepancies compared to group M. Conclusion: Milled provisional crowns demonstrated higher accuracy and fidelity to the original design projected in 3D software compared to 3D printed crowns in both areas of analysis.

KEYWORDS

Crowns; Digital Technology; Printing Three-dimensional; Workflow; Computer-Aided design.