Comparative Accuracy of Intraoral and Extraoral Digital Workflows for Short Span Implant Supported Fixed Partial Denture Fabrication: An In Vitro Study

Background:The advent of digital impressions using computer-aided design and manufacturing technology (CAD/CAM) has simplified and improved the fabrication of implant prostheses in dentistry.The conventional impression has several drawbacks, including tray selection, material type, impression technique, impression disinfection, and cast model storage.The inaccuracies caused by distortion and contraction of impression material can be minimized with digital impressions.This study aimed to compare digital dental impressions of 10 working casts made using the Pindex laser removable die system to fabricate parallel drill channels vs 10 working casts made using the Di-Lok plastic tray removable die system.Material/Methods:An implant master die with 2 dental implant analogs was fabricated.Ten working casts using the Pindex laser removable die system with parallel drill channels and 10 working casts using the Di-Lok plastic tray removable die system were fabricated.The working casts were scanned using an extra-oral laboratory scanner and the implant master model was scanned with an intra-oral scanner. Results:The properties of the casts made using the 2 systems were evaluated and analyzed with ANOVA and post hoc Tukey test.The mean horizontal linear distances between A1B1 (P<0.021),A2B2 (P<0.018),C1D1 (P<0.026),C2D2 (P<0.03),B1C1 (P<0.01), and mean vertical distances between B1A2 (P<0.015),C1D2 (P<0.001),B1B2 (P<0.028), and C1C2 (P<0.001) were significantly different between the Pindex system and Di-Lok tray system as compared to intra-oral scans. Conclusions:Complete digital workflow with intra-oral scans were more than the partial digital workflow with extra-oral scans for the Pindex system and Di-Lok tray systems.