Visual, Microscopic, Tactile and Radiographic Identification of Occlusal Caries

Objectives: Dental caries is an infectious disease that results in localized dissolution and destruction of the calcified tooth tissues and should therefore be detected as early as possible. The objective of this study was to determine the accuracy of visual, microscopic, tactile and radiographic diagnostic techniques when used by less experienced validators to identify occlusal caries. Methods: A total of 50 human molars free of large visible carious lesions or fractures, and removed for periodontal reasons, were included in this study. The examination site on each tooth was identified on a colour photograph taken of the occlusal surface of each tooth. The identified sites were assessed by 12 senior dental students, using visual (direct vision), microscopic (12,5x), tactile (Hu-Friedy XP 23/QOW explorer) and radiographic (E-speed intra-oral film) identification techniques. Thereafter a section (0,4 mm) of the identified site of each tooth was histologically analysed on an Olympus/BH-2 microscope (40x) for the presence of caries. The results were statistically analysed using a two-sided Fischer's Exact Test (p£0,05). Results: The percentage of correct identifications with respect to the histological findings were: visual (69,6%; p=0,028), microscopic (70,8%; p=0,007), tactile (72%; p=0,007) and radiographic (64,3%; p=0,107). The p-values indicating the significance of the association were £0,05 for the visual, microscopic and tactile techniques and >0,05 for the radiographic technique. Conclusions: Less experienced validators were found to be most successful in the identification of occlusal caries by means of the tactile (explorer) diagnostic technique, followed by the microscopic and visual techniques. The radiographic technique was found to be the least successful.