A radiographic method for distinguishing noncavitated from cavitated proximal carious lesions: A proof of concept...

We propose a new topical radiographic contrast method for distinguishing noncavitated from cavitated radiolucencies. Laboratory tests and a pilot clinical trial were designed to test the feasibility and efficacy of the method.

Twenty-two adults with 27 proximal radiolucencies had conventional bitewing (BW) examinations. After exclusion, 21 surfaces were evaluated. A concentrated solution of sodium iodide was placed in the interdental spaces via a microsyringe and BWs were again exposed. A class II cavity preparation was made in the adjacent tooth and polysiloxane impressions were made of the study surfaces. The impressions were scanned by visible light, creating a high resolution 3D replica. Cavitations, if present, were measured.

Nine surfaces were noncavitated and 12 surfaces were cavitated. The microsyringe dispensed a variable volume of liquid, which affected the accuracy of the test. The sensitivity for cavitation was 50%, specificity was 88.9%, and accuracy was 66.7%. This compares to a reported 60% sensitivity, 62% specificity, and 62% accuracy for BW examinations. Intraexaminer reliability for classifying noncavitated or cavitated lesions using the kappa test was 0.649.

This method needs improvement but was an advance over conventional BWs and could result in reduction of restorations in low- and high-risk patients.