An in vitro study of affected dentin as a risk factor for the development of secondary caries.

The objective of the study was to investigate the association between the presence of residual caries (inner affected dentin) on the cavity walls of cavity preparations and the further development of secondary caries lesions. Two 2 x 5 x 2 mm cavities, one in the apical portion (A) and one in the cervical portion (C) of the root, were prepared on both the lingual (L) and buccal (B) surfaces of 18 extracted human roots. The apical cavities (AB and AL) were artificially demineralized for 30 min using a decalcifying solution, followed by staining with a caries detector dye and then excavation of irreversibly demineralized dentin, leaving behind a layer of inner carious dentin.