Orange/Red Fluorescence of Active Caries by Retrospective Quantitative Light-Induced Fluorescence Image Analysis

This retrospective clinical study determined the association of caries activity and orange/red fluorescence on quantitative light-induced fluorescence (QLF) images of surfaces that progressed to cavitation, as determined by clinical visual examination. A random sample of QLF images from 565 children (5-13 years) previously enrolled in a longitudinal study was selected. Buccal, lingual and occlusal surface images obtained after professional brushing at baseline and every 4 months over a 4-year period were analyzed for red fluorescence. Surfaces that progressed (n = 224) to cavitation according to the International Caries Detection and Assessment System (ICDAS 0/1/2/3/4 to 5/6 or filling), and surfaces that did not progress (n = 486) were included. QA2 image analysis software outputs the percentage increase of the red/green components as Delta R and area of Delta R (area Delta R) at different thresholds. Mixed-model ANOVA was used to compare progressive and nonprogressive surfaces to account for correlations of red fluorescence (Delta R and area Delta R) between surfaces within a subject. The first analysis used the first observation for each surface or the first available visit if the surface was unerupted (baseline), while the second analysis used the last observation prior to cavitation for surfaces that progressed and the last observation for surfaces that did not progress (final). There was a significant (p < 0.05) association between red fluorescence and progression to cavitation at thresholds Delta R0, Delta R10, Delta R20, Delta R60, Delta R70, Delta R80, Delta R90 and Delta Rmax at baseline and for Delta R0 and Delta R10 at the final observation. Quantification of orange/red fluorescence may help to identify lesions that progress to cavitation. Future studies identifying microbiological factors causing orange/red fluorescence and its caries activity are indicated. (C) 2016 S. Karger AG, Basel