The effects of restorative material and location on the detection of simulated recurrent caries. A comparison of dental film, direct digital radiography and tuned aperture computed tomography.

OBJECTIVES

To explore the effects of restorative material and lesion location on the detection of recurrent caries using intra-oral film, direct digital radiography and unprocessed and iteratively restored tuned aperture computed tomography (TACT) images.

METHODS

An in vitro model with simulated lesions in half the surfaces studied was used. Lesions of varying sizes were created at either the intersection of the facial or lingual wall and the gingival floor or on the gingival floor midway between the facial and lingual walls in the proximal boxes of 24 molar teeth with MOD inlay preparations that had been restored with amalgam, radiopaque composite or radiolucent composite.

RESULTS

Sensitivity and specificity values based on restoration were: amalgam: 59 and 87%; radiopaque composite: 68 and 78%; radiolucent composite: 36 and 93%; based on lesion location, mid-cervical floor region: 51 and 97%; point angle region: 44 and 90%; based on imaging modality, film: 40 and 85%; digital: 44 and 76%; unprocessed TACT slices: 50 and 87%, iteratively restored TACT images: 83 and 96%. Iteratively restored TACT images had the best intra- and inter-reader agreement.

CONCLUSIONS

The use of restorative materials with a density approximating that of enamel is more effective for the detection of recurrent caries. Lesions located at the buccal point angle or mid-gingival floor are more easily detected than at the lingual point angle region. The sensitivity and specificity of TACT and iteratively restored TACT images were superior to those of film and direct digital images.