Comparison of digital intraoral scanner reproducibility and image trueness considering repetitive experience

Because the digital workflow can begin directly in the oral cavity, intraoral scanners are being adopted in dental treatments. However, studies of the relationship between the experience of the practitioner and the accuracy of impression data are needed. The purpose of this clinical study was to investigate the effect of the experience curve on changes in trueness when a patient’s complete dental arch is scanned. Twenty dental hygienists with more than 3 years of experience in dental clinical practice (group 1 had 3 to 5 years; group 2 had >6 years) were recruited to learn to operate 2 intraoral scanner systems. All learners scanned the assigned patient’s oral cavity 10 times during the experience sessions. Precision was calculated as the mean deviation among all superimposition combinations from the 10 scanned data sets of each learner [n=10C2=45]. Trueness was evaluated by superimposing the 10 consecutive intraoral scan data onto the impression scan data from each patient’s rubber impression body (n=10). The acquired images were processed and analyzed using a 3-dimensional analysis software. For statistical analysis, the independent 2-sample t test and repeated measures ANOVA were performed (α=.05). The mean precision of the Trios scanner was greater than that of the iTero (Trios, 52.30 μm; iTero, 60.46 μm; P