Course database

Development and Validation of a Novel Virtual-Fit Method for Evaluating Intraoral Scanner Accuracy

english

Borbola Dániel József

Dental Research Division

Dr. Gábor Varga

SE FOK Oktatási Centrum Árkövy terem

2026-11-27 15:00:00

Dental Research

Dr. Gábor Varga

Dr. Vág János

Dr. Haluszka Dóra

Dr. Fráter Márk

Dr. Liliom Károly

Dr. Szabó Bence Tamás

Dr. Szabó Balázs

Objectives: The thesis aimed to introduce a clinically realistic method for evaluating IOS accuracy in tooth-supported complete-arch fixed prosthodontics fabricated by CAD/CAM system. The thesis also aimed to validate the virtual-fit alignment method, to assess the influence of cement spacing on compensating scanning inaccuracies, and to compare the complete-arch accuracy of different IOSs using clinically interpretable fit parameters. Methods: In the first study, four maxillary models were scanned using an industrial reference scanner, Emerald S, and Medit i700 IOSs. Complete-arch fixed frameworks were designed with three different cement space settings: 70 µm, 70+20 µm, and 140 µm. Frameworks were aligned to the reference scan using virtual-fit alignment simulating clinical seating. Internal and marginal gaps were measured and correlated with conventional trueness values. In the second study, also four maxillary models were scanned using seven IOSs (Aoralscan 3, Emerald S, Helios 600, Lumina, Medit i700, Primescan, and Trios 5). Digital frameworks were designed with 70 and 70+20 µm spacing. Internal and marginal gaps were evaluated using the validated virtual-fit method. Results: The virtual-fit method accurately reproduced preset cement spacing with deviations of 3–13 µm. Conventional trueness metrics correlated with virtual-fit measurements but underestimated clinically relevant misfit by 2.6–4.6 times and failed to detect extreme discrepancies. A baseline internal cement space of 70 µm was sufficient for most scans, while an additional 20 µm marginal spacing improved fit in suboptimal scans; excessive spacing (140 µm) adversely affected marginal adaptation. Emerald S, Medit i700, Primescan, and Trios 5 met fit requirements for complete-arch restorations, whereas Lumina and Aoralscan3 showed greater variability and Helios 600 did not meet accuracy criteria. Increased cement spacing improved fit for less precise scanners. Conclusions: The virtual-fit method enables clinically meaningful evaluation of IOS accuracy in complete-arch fixed prosthodontics produced by CAD/CAM system. Cement spacing is a critical, workflow-dependent parameter, and conventional trueness metrics alone are insufficient to predict restoration fit. The findings support evidence-based scanner selection and CAD design optimization for reliable full-arch digital workflows.