[Study of root canal cements comprising calcium aluminate. First report on cytotoxicity].

We prepared new root canal cements for trial. These cements were comprized of calcium aluminate and calcium hydroxyde for setting in a root canal and a bioabsorbable property. The biocompatibility of these cements were then evaluated with kinds of cytotoxicity tests and were compared with three kinds of root canal cements on the market such as Calvital (CV), Canals (CA) and Neodyne (ND). As a result of the millipore filter test using HeLa cells, three kinds of trial cements and CV showed moderate cytotoxicity at every stage. The toxicity of CA and ND were related to the period of administration and the two products showed severe cytotoxicity 24 hours after the administration. The cell growth inhibition test using L-929 cells revealed that the inhibition of the three kinds of trial cements was based on a strong alkalinity caused by calcium hydroxyde and the inhibition on the cell growth was related to the calcium hydroxyde content in these cements. However, the inhibition of these cements was smaller than that of CV and they showed no inhibition in the last stage of the cell culture, while CA and ND caused the mild inhibition. Therefore, we have concluded that these trial cements are useful for root canal filling because they have better affinity to the cultured cells than CV, CA and ND.