[Effect of dental luting cements from the viewpoint of cell recovery (in vitro)].

Cell recovery of four cell lines [L-929 cells, HEp-2 cells, Gin-1 cells and the cells from human dental pulp tissues (Hp cells)] was examined after exposure to four zinc phosphate cements, five polycarboxylate cements, three glass ionomer cements, five resin based cements and one zinc oxide-eugenol.EBA cement. Phosphate cements, glass ionomer cements and zinc oxide-eugenol.EBA cement were markedly cytotoxic to the four cell lines 3 hours and 24 hours after mixing. Polycarboxylate cements considerably inhibited cell recovery of the three types of cells except Hp cells even 24 hours after mixing, compared to the gradual recovery of Hp cells after mixing. Two of the resin based cements inhibited cell recovery, while the three others allowed moderate cell recovery. The pH values of the medium used for the experiments was 6.6-6.8 for phosphate cements, glass ionomer cements and zinc oxide-eugenol.EBA cements. Polycarboxylate cements had no effect on the pH. On the other hand, in resin based cements the pH was shifted from acidic to basic. The solubility of the materials used was, in decreasing order: glass ionomer cements, zinc oxide-eugenol.EBA cement and one of the resin based cements, polycarboxylate cements, phosphate cements and another resin based cement, and the other three of resin based cements (lowest). The difference in cell recovery was considered to be due to composition and solubility of the materials.