Comparison of Accuracy between Digital and Conventional Impression Techniques in Full-Arch Edentulous Implant Patients: An In Vitro Study

Introduction: We aimed to compare the accuracy of digital and conventional impression techniques in full-arch edentulous implant patients and to evaluate the impact of using an auxiliary geometry part (AGP). Methods: A mandibular edentulous stone cast with four multiunit abutment analogs was fabricated as the master cast. This cast was scanned using an industrial scanner to generate reference data. Impressions were then obtained using three techniques: intraoral scanning (IOS), IOS with an AGP (IOS-AGP), and the open-tray splinted conventional technique (OTS). The precision of the impression methods was evaluated by measuring the distance and angle between the right distal implant and the other three implants. Precision was assessed using the coefficient of variation. Results : Regarding distance assessments IOS-AGP group showed a statistically significant lower coefficient of variation in comparison with IOS and OTS. Regarding angle assessments, we found statistically nonsignificant differences among IOS, OTS, and IOS-AGP groups. Conclusion: Full-arch digital implant impressions using IOS-AGP provided superior accuracy for distance measurement compared to conventional impressions.