Detection of natural white spot caries lesions by an ultrasonic system

Ultrasound has been used in industrial business as one of the nondestructiv e measurement methods. It was hypothesized that nondestructiveness of the u ltrasonics could be useful in determination of demineralization of noncavit ated carious lesions on human enamel. This investigation was designed to de termine the presence of natural carious lesions on proximal surfaces of hum an molar teeth using an ultrasonic system compared to radiography and histo logy as the gold standards. Measurements were made directly from proximal s urfaces of 20 mandible molar teeth with white spot carious lesion by 2 exam iners independently with the ultrasonic system. Ultrasonic evaluation of ea ch natural white spot lesion had a sensitivity of 88%, specificity of 86%, positive predictive value of 88% and a negative predictive value of 86%, an d the chance-corrected agreement was also satisfactory ( x=0.74) compared t o histology, The radiograph demonstrated chance-corrected agreement of 0.41 :0.38 for the first and second examiners, respectively, Duncan test analysi s of the numerical values was significantly different for the intact and th e noncavitated carious surfaces (p<0.05), The results indicated that the ul trasonic evaluation is a sensitive method for the detection of the natural white spot carious lesions and can differentiate the changes in elastic pro perties of enamel numerically. Copyright (C) 2000 S. Karger AG. Basel.