In vivo detection of non-cavitated caries lesions on occlusal surfaces by visual inspection and quantitative light-induced fluorescence

Objective. The aim of this clinical caries detection study was to compare the outcome of quantitative light-induced fluorescence (QLF) and meticulous visual inspection (VI) in detecting non-cavitated caries lesions on occlusal surfaces in young adolescents. It was hypothesized that the respective diagnostic performances of meticulous VI and QLF are similar. Material and methods. The subjects were 34 fifteen-year-old students. Five-hundred-and-seventeen cleaned occlusal surfaces were air-dried and examined using VI. Fluorescence images were captured with QLF equipment and custom software was used to display, store and analyze the images. The area of the lesion (area; mm2), fluorescence loss (ΔF;%) and ΔQ (Area*ΔF; mm2*%) were determined at a QLF threshold of −5%. The presence/absence of non-cavitated lesions was independently recorded with both methods. Results. 78.8% of all untreated surfaces were classified as sound or as having a non-cavitated lesion with both methods uniformly (VI+QLF). On 7.1% of all surfaces a lesion was detected by VI only and on 14.1% by QLF only. All parameters (Area, ΔF, ΔQ) differed significantly between lesions registered with both methods (VI+QLF) and lesions recorded with QLF only. Conclusions. It was concluded that our hypothesis cannot be confirmed. The study shows that QLF detects (1) more non-cavitated occlusal lesions and (2) smaller lesions compared to VI. However, taking into consideration time-consuming image capturing and analysis, QLF is not really practical for use in the dental office.