Abstract
The present study aimed to develop a method for conserving dentin that has been demineralized, which in principle is completely removed, by rehardening it. It has been reported that artificial demineralized root canal dentin was prepared when bovine dental root was demineralized from within the root canal using a rapid-decalcification agent (K-CX). Furthermore, when this artificial dentin was applied inside the root canal using nano-hydroxyapatite (nano-HA), the artificial demineralized root canal dentin was found to reharden to the same degree of hardness as undecalcified dentin. However, while the artificial demineralized root canal dentin that had been prepared as the test sample was free of bacterial infection, infected root canals seen in the clinical setting often contain large numbers of bacteria, and it is unclear how these bacteria affect the rehardening of demineralized root canal dentin using nano-HA. Consequently, we prepared artificial demineralized root canal dentin that had been in contact with oral saliva, and then applied nano-HA in the same manner. The results demonstrated that the artificial demineralized root canal dentin that had been in contact with oral saliva rehardened to the same degree of hardness as undecalcified dentin.The fact that the quintessential strength of dentin could be obtained regardless of whether or not bacteria were present suggests that it may be possible to conserve demineralized root canal dentin, which until now it has been necessary to remove, for reuse in later prosthetic therapy.
