The impact of different dental restorations on detection of proximal caries by cone beam computed tomography

To evaluate the effects of different types of restorations on observer ability to detect proximal caries in CBCT images. Forty human premolars and molars with artificial proximal caries were placed proximal and distal to 5 molars having different restorations (amalgam, composite, resin-modified glass ionomer cement (RMGIC) fillings, zirconia, and lithium disilicate crowns) and a non-restored molar. CBCT scans were obtained using i-CAT® Next Generation. Images were rated twice by 2 observers. The exact depth of artificial caries was histologically established. Sensitivity, specificity, and area under the receiver operating characteristic curve (Az) values were calculated. Caries detection in teeth surfaces mesial and distal to amalgam showed compromised specificity and accuracy. Moreover, caries detection in teeth surfaces mesial to zirconia crown showed low sensitivity, specificity, and accuracy. Capability of CBCT in detection of proximal caries in teeth adjacent to composite, RMGIC, and lithium disilicate was comparable to those adjacent to non-restored molar. CBCT scans performed for tasks other than caries detection should be assessed for proximal caries in absence of any restorations as well as in presence of composite, RMGIC fillings, and lithium disilicate crowns. However, CBCT should not be used for proximal caries detection in teeth adjacent to amalgam and teeth surfaces mesial to zirconia crowns. It is important to investigate the influence of artifacts produced by various restorations on CBCT-based caries detection to optimize CBCT benefits, caries diagnosis and avoid unnecessary treatment of sound surfaces.