Near-infrared light reflection for the early detection of proximal caries in posterior teeth: an in vivo study

Abstract

Background: The purpose of this study was to evaluate the validity of near-infrared light reflection for detecting different depths of proximal caries in posterior teeth and to compare it with commonly used clinical oral examinations and bitewing radiography images. Methods: Twenty-six patients with a total of 516 proximal surfaces were included in this study. The ground truth of the proximal caries was determined through a consensus reached by two experienced dentists after an intraoral examination assisted by bitewing radiographs. Two general dentists assessed the condition of proximal caries on posterior teeth on near-infrared light reflection images. Accuracy, sensitivity, and specificity were evaluated to determine the diagnostic efficacy of near-infrared light reflection for detecting proximal caries in posterior teeth. Results: For posterior teeth, the accuracy of near-infrared light reflection was 0.78, with a sensitivity of 0.44 and a specificity of 0.83. Cohen’s kappa showed poor consistency between the two diagnostic methods, near-infrared light reflection and bitewing radiography. Conclusion: Near-infrared light reflection is an effective clinical tool for detecting proximal caries in posterior teeth, yet this method does not demonstrate superiority over traditional methods such as bitewing radiography. Trial registration: The clinical trial was registered with the China Clinical Trial Registry (https://www.chictr.org.cn/) on 18 August 2023 under the trial number ChiCTR2300074877.