Methods: SS-OCT images and bitewing X-ray photograms were obtained form 50 proximal surfaces of 30 patients, and examined the presence and extent of caries lesion using depth scale (0: Sound tooth surface. 1: Superficial demineralization of enamel but without cavitation. 2: cavitated enamel caries. 3: Superficial dentin caries extended within the outer half of total thickness of dentin. 4: Deep dentin caries extended into the inner half of total thickness of dentin.). The results were compared with the clinical observations after the caries treatment. The sensitivity, specificity and Az value of ROC analysis were calculated and statistically analyzed at significance level of p = 0.05.
Results: SS-OCT could detect the presence of proximal caries in tomogram synthesized based on the backscattered signal. SS-OCT showed significantly higher sensitivity than bitewing X-ray for the detection of cavitated enamel lesion and dentin caries (Student t-test, p < 0.05). ROC analysis also showed the superior results of SS-OCT over that of the X-ray for the detection of cavitated caries and dentin caries (Student t-test, p < 0.05). No significant difference of specificity was found between SS-OCT and bitewing X-ray in all diagnostic thresholds. (Student t-test, p > 0.05).
Conclusions: Within the limitation of this clinical study, detection of cavcitated caries on the proximal surfaces using SS-OCT correlated well with the clinical results after the caries treatment.