Comparison accuracy of digital and analog method using milled occlusal splints

Abstract Objective This clinical trial aims to compare the accuracy of interocclusal registration in centric relation taken with polyvinyl siloxane and intraoral scanner (IOS) with the fabrication of occlusal devices. Methods Thirty‐one participants were included in the trial registered at ClinicalTrials.gov (NCT05317182) receiving two different occlusal devices from two different workflows. One workflow was performed using polyvinyl siloxane impression material and the other with IOS. Every splint was scanned before and after the occlusal adjustments to compare the volumetric changes using the Root Mean Square deviation (RMS). Furthermore, three evaluators assessed the 3D comparison using color maps in a Visual Analog Scale (VAS). Results The average values of RMS were higher for the analog approach (0.01 ± 0.067) than the digital approach (0.065 ± 0.035). However, the differences were not statistically significant ( p < 0.063) between the two impression techniques. For the semiquantitative analysis performed by blinded evaluators, differences in VAS values between the impression for the digital (2.08 ± 2.4) and analog (3.80 ± 3.3) technique were statistically significant. The three evaluators agreed in more than 90% of the qualitative dichotomous evaluation. Conclusion Digital impressions did not show inferior accuracy compared to conventional impressions when assessed using quantitative measurements. Clinical Significance This clinical trial provided evidence on registering interocclusal relationship at increased vertical dimension with fully digital workflow for complete arch prosthesis.