QLF-D와 OCT를 이용한 초기 인공우식병소의 변화 탐지

Abstract

Objectives: We aimed to compare the differences in caries lesion changes when measured by QLF-Das fluorescence loss and by SS-OCT as lesion depth with respect to demineralized time, during formation of artificial early caries lesion. We also demonstrated that QLF-D and SS-OCT can be used effectively in monitoring the longitudinal progression of simulated caries lesions. Methods: Ten bovine incisors were sectioned (5×4 mm) and embedded in epoxy resin. An acidresistantnail varnish was applied to a part of the tooth surfaces to protect sound enamel (2×4 mm). To generate lesions, each specimen was immersed in 40 ml of a demineralizing gel for 20 days at 37oC. To measure mineral loss of the demineralized specimens, fluorescence loss (ΔF, %) was measured byQLF-D and lesion depth (μm) was determined by SS-OCT from the captured cross-sectional image. All the specimens were analyzed daily by QLF-D image analysis software and SS-OCT image analysis program for 20 days. The repeated measures analysis of ΔF and lesion depth was used. The pairedt-test was used to assess differences between each day. The correlation between ΔF and lesion depth was determined using the Pearson`s correlation coefficient. Results: On the 5th, 10th, and 15th day, compared to baseline values, ΔF decreased in 12.7%, 25.0%, and 33.6% of the specimens, respectively, and the lesion depth increased in 9.9%, 16.0%, and 22.6%of the specimens, respectively. However, after 15 days, there was no change in the ΔF and lesion depth. High significant correlation was identified between the resultant values of ΔF obtained by QLF-D and those of lesion depth obtained by SS-OCT (r = ―0.811, P<0.0001). Conclusions: The QLF-D and SS-OCT could detect subtle changes in mineral loss and lesion depth with respect to demineralized time. Furthermore, these devices were useful for monitoring changes in mineral amount and lesion depth.