Qualitative laserfluorescence in the diagnosis of the cavity limit

Abstract

Introduction: laser-induced fluorescence is capable of discerning between healthy and diseased tissue and has been applied to different areas within Dentistry. However, qualitative laserfluorescence has been little studied to determine the cavity limit. Objective: to evaluate the effectiveness and safety of the use of laser fluorescence, at λ=450 nm and 405 nm, in detecting the cavity limit. Method: 45 teeth were selected ex-vivo, which presented at least one location of dentin caries. 83 areas were determined for the study in which fluorescence was measured using three systems with different wavelengths (405-450 nm). The safety of the test was calculated with the color categories recommended by the manufacturer and a scale resulting from the recoding of the variables. Using the Pilxelmator MAC software, the RGB color variables were converted into quantitative values of the CIE scale. The data were entered into the SPSS 19.0 statistical program. Significance tests were applied (α≤0.05). Results: the color categories recommended by the manufacturer do not match the scales that show the best sensitivity and specificity. Laserfluorescence (405 nm-450 nm) is more specific than sensitive. The L*a*b variables are capable of differentiating between recoverable and non-recoverable dentin and the LIF-405 nm discriminates between the layers that delimit the cavity boundary. Conclusions: laser-induced fluorescence is a useful method for diagnosing the cavity limit, although the manufacturer's recommendations must be modified. The L*a*b system can help eliminate operator subjectivity.