Accuracy of extraoral tuned aperture computed tomography (TACT) for proximal caries detection

ObjectivesThe objectives of this study were to compare the difference in the accuracy of proximal caries detection by extraoral tuned aperture computed tomography (TACT), intraoral TACT, and film radiographs.Study designEighty proximal surfaces of 40 extracted human maxillary teeth were used. A digital sensor was the image receptor for TACT. Film radiographs were acquired using Insight film. Nine basis images were acquired to reconstruct TACT slices. Seven observers scored the presence or absence of proximal caries using the 3 imaging modalities. The true presence of caries and its depth were determined using the sectional images obtained by micro CT. Among the image modalities and observers, possible differences in the area under the receiver operating characteristic curve were assessed by analysis of variance (ANOVA).ResultsANOVA indicated no statistically significant differences between observers (P = .845), modalities (P = .657), and observer-modality combinations (P = .593).ConclusionWithin the limited range of this study, extraoral TACT was not statistically different from intraoral TACT or film radiographs for proximal caries detection. This suggests that extraoral TACT may have some clinical utility for caries diagnosis and that further study may be warranted.