Accuracy of intraoral scan with prefabricated aids and stereophotogrammetry compared with open tray impressions for complete-arch implant-supported prosthesis: A clinical study

Objectives: The aim of this clinical study was to compare the accuracy of intraoral scan system (IOS) with prefabricated aids and stereophotogrammetry (SPG) compared with open tray implant impression (OI) for complete-arch implant-supported fixed dental prostheses (CIFDP). Materials and methods: Patients needing CIFDP were enrolled in this study. OI, reference standard, IOS with prefabricated aids, and SPG were performed for each patient. Distance and angle deviations between all pairs of abutment analogs, root mean square (RMS) errors between the aligned test and reference model, and chairside time were measured. The effect of inter-abutment distance, jaw (maxilla or mandible), number of implants, and arch length on deviations was analyzed. The mixed effect model was applied to analyze deviations and RMS errors. Results: Fifteen consecutive individuals (6 females and 9 males, 47-77 years old) with 22 arches (9 upper and 13 lower jaws) and 115 implants were included. There was no significant difference in distance deviation comparing SPG and IOS with OI (p >.05). IOS showed a significantly greater angle deviation and RMS errors than SPG (median 0.40 degrees vs. 0.31 degrees, 69 mu m vs. 45 mu m, p <.01). The inter-abutment distance was negatively correlated with the accuracy of SPG and IOS ( p <.05). The chairside time for IOS, SPG, and OI was 10.49 +/- 3.50, 14.71 +/- 2.86, and 20.20 +/- 3.01 min, respectively ( p <.01). Conclusions: The accuracy of SPG and IOS with prefabricated aids was comparable. IOS was the most efficient workflow.