Intraoral Scanner Images Showed High Specificity for Caries Around Restorations

Edited by Dentaltown staff

Images from a 3D intraoral scanner identified caries lesions around existing restorations with high specificity but variable sensitivity compared with visual-tactile clinical examination, according to a diagnostic accuracy study published online Oct. 19 in Clinical Oral Investigations.

Researchers assessed 299 amalgam and composite resin restorations in 41 adult patients at the Federal University of Pelotas dental clinic in Brazil between July 2023 and September 2024. Visual-tactile clinical examination served as the reference standard. Scans were taken with a 3Shape TRIOS 3 scanner under standard white light, and the images were graded using severity categories derived from the CARS criteria for caries around restorations. Two trained, calibrated examiners performed the clinical assessments, and a third assessed the scanner images.

Sensitivity was 75% at the initial lesion threshold, 40% at the moderate threshold, and 57.1% at the severe threshold. Specificity was 84.1%, 97.4%, and 99.7% at the same thresholds, and areas under the curve were 0.79, 0.69, and 0.78.

At the severe threshold, the positive predictive value was 80% and the negative predictive value 99%. Clinical and scanner assessments agreed exactly 77.9% of the time, with a linearly weighted kappa of 0.53.

Bruna Machado Fernandes, Anelise Fernandes Montagner, Françoise Helene van de Sande, and Marcos Britto Correa of the Federal University of Pelotas and Sarah Arangurem Karam of the Catholic University of Pelotas conducted the study. The authors reported support from Brazilian research funding agencies and declared no competing interests.

The authors described the scanner as a complementary tool and said the sensitivity estimate at the severe threshold was imprecise because few severe lesions were found. They recommended interpreting scanner images alongside visual-tactile examination and radiographs when indicated, and called for larger studies.

Sources:
Clinical Oral Investigations, “Validation of 3D intraoral scanner use for detecting caries lesions around dental restorations: A diagnostic accuracy study,” published online Oct. 19, 2026: link.springer.com/10.1007/s00784-026-07226-7