Validity of MicroCT for in vitro detection of proximal carious lesions in primary molars

ObjectiveThis study aimed to validate the MicroCT for detection of proximal carious lesions in primary molars, using histology as the gold standard.MethodsForty-eight proximal surfaces of primary molars were examined. Two calibrated examiners conducted the examinations independently. Proximal surfaces were visually scored, using ICDAS. Bitewing radiographs, Micro-CT and histological analyses used caries scores: 0 = sound; 1 = outer enamel; 2 = inner enamel; 3 = not spread dentine; 4 = outer dentine; 5 = inner dentine. Axial and sagital images were used for Micro-CT analysis, whilst for histology, tooth sections (400 μm) were analyzed stereomicroscopically (×15).ResultsInter-examiner agreement ranged from 0.87 to 0.93 kappa coefficient (k). Histological analysis revealed a frequency of sound tooth surfaces (18.8%) enamel carious lesions (E1) (48%) and dentine carious lesions (D1) (33.3%). MicroCT showed high correlation with histology (rs0.88). At both diagnostic thresholds (E1 and D1), sensitivity and accuracy were higher for MicroCT. Inter-device agreement between MicroCT and histology was k = 0.81. No difference was found between MicroCT and histology as gold standards for detecting carious lesions using ICDAS.ConclusionMicroCT can be used as a gold standard for detecting carious lesions in proximal surfaces in primary molars.