Accuracy Of 3 Implant Impression Techniques In 2 Intraoral Scanners

To investigate the accuracy of 3 intraoral scanner (IOS)-based complete-arch implant impression techniques using 2 IOSs. An edentulous maxillary model with 6 screw-retained abutment (SRA)-level scan bodies (SBs) was constructed. A control group was generated using a desktop scanner. Three IOS-based scanning techniques were tested: (1) without scan aids (no-SA), (2) with scan aids but without calibration (SA), and (3) with scan aids and perform calibration (CA). 3Shape TRIOS 3 (TR) and Shining3d Aoralscan 3 (AO) IOSs were used. Each technique was repeated 10 times on each scanner. SBs in the tested groups were superimposed onto the control group. For each SB, the linear trueness and precision were compared. In both IOSs, trueness of the SA group (272.32 μm for TR; 240.00 μm for AO) was higher than that of the no-SA group (606.77 μm for TR; 413.78 μm for AO) (all P<0.05). Furthermore, the calibration process further improved trueness (70.51% improvement for TR; 28.00 % improvement for AO). For precision, the SA group (75.60 μm for TR; 69.91 μm for AO) and the CA group (74.36 μm for TR; 79.42 μm for AO) outperformed the no-SA group (487.75 μm for 3S; 160.74 μm for AO) (all P<0.05). The accuracy of IOS-based full-arch implant impressions can be significantly improved by using scan aids combined with a calibration process.