In vivo reproducibility study of ultrasound for monitoring enamel thickness

Objectives: This work assesses ultrasound’s reproducibility for monitoring enamel thickness in vivo. Study Design: This clinical reproducibility study recruited thirty healthy consented volunteers. The enamel thickness on an intact maxillary central incisor was evaluated at three sites on three separate visits, one week apart. Bland Altman statistical test and intra-class coefficients (ICC) were used to assess reproducibility. Results: Reproducibility results were highest for the cervical site (Bias (mm) = -0.01, 95 % limits of agreement = -0.05, 0.04) followed by mid-buccal (Bias = 0.01, 95 % limits of agreement = 0.04, 0.06) and incisal site (Bias = 0, 95 % limits of agreement = -0.25, 0.25). ICC was highest for the cervical site (0.96) followed by mid-buccal (0.71). Conclusions: Ultrasound is a sufficiently reproducible and reliable technique for monitoring change in enamel thickness, as in erosive tooth surface loss (TSL). The preferred sites for ultrasonic measurements are cervical and mid buccal.