Precision of complete-arch digital implant scans using photogrammetry and intra-oral scanning. An in vivo cross-over study.

To evaluate the precision of complete-arch digital implant scans using intraoral scanning (IOS) and photogrammetry (PG). Nineteen completely edentulous arches were included. Each arches contained at least four implants. Abutment-level digital scans were taken using IOS (3Shape Trios 3) and PG (Imetric ICam 4D, 1st gen). Each arch was scanned five times with each device. Implant cartesian coordinates were extracted, and the Spatial Fit, Cross-Arch Distance, and Virtual Sheffield tests were conducted. A generalized estimating equation (GEE) analysis was conducted to compare the precision of IOS and PG for the three tests. A GEE was used to assess further the association between jaw type (maxilla vs. mandible) and the precision for each device in all three tests. The significance level was set at α=0.05. PG demonstrated greater precision in all three tests (p < 0.0001). Precision was not significantly associated with jaw type in the PG group (p > 0.05). For IOS, the mandibular arch demonstrated inferior levels of precision compared to the maxilla for the Spatial Fit (p = 0.040), Cross-Arch Distance (p = 0.026), and Virtual Sheffield (p = 0.019) tests. PG represented a more precise scanner for complete-arch digital implant scans. Maxillary arch scans were associated with superior precision compared to scans of the mandible, yet statistical significance was only found in the IOS group. IOS scanning for fixed implant rehabilitation of the edentulous jaw with conventional scan bodies should be approached with caution due to the poor precision, particularly in the mandible. PG represented a more precise scanner for complete-arch digital implant scans.