Saturday, April 4, 2009: 1:45 p.m. - 3 p.m.
Location: Exhibit Hall D (Miami Beach Convention Center)
Objective: To determine the accuracy of hi-res digital bitewing images in diagnosing incipient proximal caries. Materials and Methods: Forty-eight human posterior teeth with proximal white spot lesions and 72 teeth with no white spot lesions were selected and 24 digital bitewings were acquired. Three observers analyzed all bitewings on a 3 MP hi-res display. All mesial and distal surfaces were evaluated on a scale of 1-5 to determine the presence or absence of caries (1 = No caries and 5 = Caries present). If a surface was scored as 4 or 5, it was further evaluated to determine the extent of the lesion: C1 = caries in outer half of enamel, C2 = extending to the DEJ, C3 = caries in outer half of dentin, C4 = extending into inner half of dentin. The depth of each lesion was measured in millimeters. MicroCT images of all teeth were acquired and depth of all carious lesions was measured. Results: For the presence of mesial incipient lesions, the observers agreed with the reference-standard for 73.8%, overestimated 6.0% and underestimated 20.2% of the lesions and for the distal lesions these values were 72.6%, 3.6% and 23.8% respectively. For the extent of mesial incipient lesions, observers agreed with the reference-standard for 28.6% and underestimated 71.4% of the lesions whereas these values were 20.6% and 79.4% respectively for the distal lesions. For depth of mesial lesions, the mean value for reference-standard was 1.4 and for observers it was 1.3 and for the distal lesions these values were 1.17 and 1.05 respectively. Conclusion: The observers performed well in determining the presence of interproximal incipient carious lesions in hi-res digital bitewing images when viewed on hi-res display but underestimated the extent of a significant percentage of lesions. The underestimation of extent, however, was not statistically significant.