Influence of different manufacturing materials on the accuracy and fitting of full-arch restorations using a...

This study aimed to assess the accuracy of a photogrammetry scanner and evaluate the influence of four different manufacturing materials on the accuracy and fitting of full-arch restorations made using a photogrammetry scanner.

A cast with six implant abutment analogs was made. Four groups (n = 9) were created according to the material used: 3D printing resin (OnX), milled resin (PMMA), titanium (Ti), and zirconia (Zir). Nine initial scans were taken using a photogrammetry scanner, and the restorations were designed and fabricated from these digital impressions. Reverse scan bodies (MicronMapper Fit Check) were screwed to the final restorations, and scanned again using the photogrammetry scanner. Linear and angular deviations between reference and test scans were calculated using root mean square error (RMSE). Passive fit was qualitatively assessed by three independent evaluators. Data were analyzed using Kruskal-Wallis, followed by Bonferroni post-hoc correction (𝛼 = 0.05). Cohen's Kappa was used to assess the agreement on the fit of restorations.

Significant differences in accuracy were found among the material groups (p < 0.05). Ti and Zir groups showed the lowest deviation values, followed by PMMA and OnX. Qualitative assessments supported the quantitative findings, with titanium and zirconia demonstrating superior passive fit. OnX showed the highest deviation and inconsistent seating and adaptation, while PMMA showed moderate results.

While photogrammetry provided clinically acceptable capture of implant position, the manufacturing material significantly affected the accuracy and passive fit of full-arch implant-supported restorations produced via photogrammetry-based workflows and alternative solutions should be used to validate the accurary of the manufacturing process in digital workflows. Titanium and zirconia demonstrated the best overall performance, supporting their suitability for final restorations. PMMA may be acceptable for provisional use, while 3D-printed resin showed limited reliability. When checking passive fit, all screws should be tightened simultaneously.