Pilot clinical study to assess caries lesion activity using quantitative light-induced fluorescence during dehydration

This study aimed to evaluate the ability of quantitative light-induced fluorescence (QLF) to assess caries lesion activity using visual examination (VE) as the gold standard. Twenty-four visible white spot lesions on buccal surfaces were examined from 23 children, ages 9 to 14 years. At baseline, the surface was hydrated with water, and thereafter, it was dehydrated with continuous compressed air during image acquisition. QLF images were acquired at 0 (baseline), 5, and 15 s. QLF variables [QLF(V): fluorescence loss (Delta F), lesion size (S), Delta Q: Delta F x S] was recorded. Changes-in-QLF(V) per second (Delta QLF(V)) were determined:Delta QLF(V) = (QLF(VN) - QLF(VBaseline)/N , where N indicates dehydration time. One experienced dentist conducted VE independently using a dental unit's light, compressed air, and explorer. QLF(V) and Delta QLF(V) of the active group (n = 11) were compared with those of the inactive group (n = 13) using two-sample t-tests. As the surface was dehydrated, S and Delta Q values of the active group increased, whereas QLFV of the inactive group showed only a small change. Delta QLF(V) of the active group were larger than those of the inactive group; however, the difference did not reach statistical significance (p > 0.11). Within the limitations of this study, QLF data indicated increments for lesions designated as active and minimal change for lesions defined as inactive. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)