Accuracy of Extraoral Bitewing Compared with Histopathology in Proximal Caries Detection of Primary Molar Teeth

Abstract

An accurate diagnosis of dental caries leads to a suitable treatment plan and prevents premature loss of primary teeth. Intraoral bitewing radiography helps caries determination but has limitations in pediatric patients with severe gag reflexes while the extraoral bitewing radiograph resolved the patients who refused to undergo intraoral radiographs. The research objective was to compare the accuracy of extraoral bitewing radiography and the gold standard histopathological examination for proximal caries detection in the primary molars. Twenty-four extracted primary molars with and without proximal caries were divided into three groups and arranged in the mimetic alveolar sockets of a 3D-printed skull and mandible. Two observers evaluated extraoral bitewing images separately twice at one-week intervals. The weighted kappa coefficients showed excellent intra-observer and inter-observer agreements between each session of the extraoral bitewing radiographic assessments. The Mann-Whitney U test showed no difference between the radiographic grading scores of extraoral bitewing images and the gold standard. The sensitivity, positive predictive value (PPV), negative predictive value (NPV), and the area under the receiver operating characteristic (ROC) curve in cavitated carious lesions were higher than in non-cavitated carious lesions. In conclusion, extraoral bitewing is an alternative radiography for pediatric patients who are either uncooperative or intolerant to intraoral radiography.