COMPARISON OF PHOTOTHERMAL RADIOMETRY AND MODULATED LUMINESCENCE, INTRAORAL RADIOGRAPHY, AND CONE BEAM COMPUTED TOMOGRAPHY FOR DETECTION OF NATURAL CARIES UNDER RESTORATIONS

Abstract

<h3>Background</h3> Intraoral radiographs (IR) are commonly used to evaluate for caries but require approximately 30% to 40% mineral loss before detection, thereby necessitating techniques with a high sensitivity index for early detection. Photothermal radiometry and modulated luminescence (PTR/LUM) offers a potentially more sensitive and safe method for detecting recurrent caries; however, there are no published studies comparing its use in detection of recurrent caries under composite restorations relative to IR and cone beam computed tomography (CBCT). <h3>Objective(s)</h3> The aim of this in vitro study was to compare the sensitivity, specificity, and receiver operating characteristic area under the curve (ROC AUC) of a caries diagnostic system based on PTR/LUM to digital IR and CBCT in detecting simulated recurrent decay under restorations. <h3>Study Design</h3> The study used 54 teeth with Class II composite restorations on 70 proximal surfaces; 35 had caries lesions remaining, and 35 were sound. The gingival floor of the restored surfaces was assessed for presence or absence of caries under composite restorations using each of the 3 modalities. Statistical calculations and analysis were performed using the R statistical computing environment. Sensitivity and specificity were calculated for each device, for each rater and image combination, and ROC analysis was performed. <h3>Results</h3> Average sensitivity across the 6 experienced dentists was 0.40 for both IR and CBCT. However, the sensitivity for the PTR/LUM was 0.89. Specificity of PTR/LUM and IR was 0.80, whereas the CBCT method was 0.70. The intrarater agreement varied for different observers with the use of IR and CBCT, ranging between moderate and substantial with only 1 observer having poor intrarater agreement for both methods. PTR/LUM showed only moderate agreement. <h3>Discussion/Conclusions</h3> PTR/LUM, which involves nonionizing radiation, can serve as a sensitive adjunct in early caries detection and monitoring.