Accuracy of a Novel Intraoral Photogrammetry Technique for Complete-Arch Implant Impressions: An In Vitro Study

Abstract

Objectives: To compare the accuracy of complete-arch implant impressions using four digital techniques: extraoral photogrammetry (EPG), intraoral scanning with original scan body (IOS), intraoral scanning with prefabricated aids (IOSA), and intraoral photogrammetry (IPG). Materials and Methods: One edentulous maxillary master model with six parallel abutment analogs was scanned by a laboratory scanner as the reference scan. EPG, IOS, IOSA, and IPG were used to scan the master model with respective scan bodies as test scans. Ten scanning data were gained for each technique. Trueness and precision of root mean square (RMS) errors were measured between the test and reference scans. Deviations in distance and angle relative to the reference scan between all pairs of abutment analogs were measured. Scanning time was recorded. Results: IPG showed significantly best trueness in RMS errors (IPG, 26.37 ± 1.02 μm; EPG, 31.72 ± 0.59 μm; IOS, 39.93 ± 7.98 μm; IOSA, 50.60 ± 12.46 μm), (all p < 0.050). EPG showed significantly best precision in RMS errors (EPG, 2.30 ± 1.31 μm; IPG, 4.12 ± 0.87 μm; IOS, 33.38 ± 13.95 μm; IOSA, 28.35 ± 11.48 μm), (all p < 0.001). IPG demonstrated significantly best performance in distance deviation (IPG, 28.59 ± 24.75 μm; EPG, 55.55 ± 37.82 μm; IOS, 62.97 ± 50.60 μm; IOSA, 93.37 ± 72.15 μm), (all p < 0.050). No significant differences were found regarding angle deviation (p = 0.313). IOSA showed the longest scanning duration (IPG: 50.30 ± 6.77 s; EPG: 57.40 ± 5.19 s; IOS: 91.10 ± 20.31 s; IOSA: 125.00 ± 18.74 s), (all p < 0.001). Conclusions: IPG achieved comparable accuracy with EPG in complete-arch implant digital impressions in vitro. IPG offers an efficient and straightforward workflow, making it a valuable alternative method; however, further clinical studies are needed to validate its efficacy.