Accuracy of a digital removable partial denture fabricated by casting a rapid prototyped pattern: A clinical study

Statement of problem A limited number of clinical studies have evaluated the accuracy of a digitally generated removable partial denture (RPD) intraorally. An analysis of the accuracy of the digital RPD on a larger number of participants was needed. Purpose The purpose of this clinical study was to analyze the accuracy of digital RPDs by using the replica technique. Material and methods The fit accuracy of digital RPDs fabricated using electronic surveying was analyzed by fabricating replicas with silicone registration material and measuring with a stereomicroscope and image program. A total of 348 measurements in 10 participants were analyzed. The internal discrepancy of the metal framework was evaluated among participants using different Kennedy classifications. The accuracy of fittings in the cingulum and occlusal rest areas were compared according to the denture support type and the measured position below the rest. A 2-way and 1-way ANOVA and an independent 2-sample t test were used for statistical analysis (α=.05). Results Statistically significant differences were found in the internal discrepancy of the various framework components (P<.05), but no differences were found among participants with different Kennedy classifications (P>.05). The discrepancy under the periphery of the rest was determined to be smaller than that of the center, especially for the cingulum rest (P<.01). Conclusions Digital RPDs fabricated using electronic surveying varied in accuracy of fit. According to the rest contact positions, the accuracy observed at the periphery was better than at the center.