Investigation of cytotoxic effects of new developed dentin bonding systems

Objective: The effects on the pulp of dentin bonding systems are significant for being close relationship with vital dentin-pulp complex. The aim of this study, three one-step dentin bonding systems which have different contents and features, evaluates cytotoxic effects on human dental pulp fibroblast cells by using tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide test (MTT assay) for 24, 48 and 72 hours. Materials and Methods: In this study, one-step dentin bonding systems such as 3M ESPE Universal Single Bond, Clearfil S3 Bond Plus, GC-Gaenial bond, were tested. Culture medium containing only serum was used as control group. Dentin bonding systems were assessed cytotoxic effects before and after polymerization by MTT assay. The obtained data was evaluated with Statistics of IBM SPSS 20.0 software package. Quantitative data was summarized by means and standard deviations. Results: The cytotoxic effect of Clearfil S3 Bond Plus group was significantly observed higher as compared to their effects on viable cell counts of the dentin bonding systems. Gaenial Bond group was significantly observed lower cytotoxic effect (p <0.05). The count of viable cells significantly decreased in all of nonpolymerized dentin bonding systems of 1/1000 dilution (p <0.05). Different times and different concentrations of all dentin bonding systems significantly increased the count of viable cells compared to the control group at least twice (p <0.05). Result: New developed dentin bonding systems may have some disadvantages on the viability of cells, although there are advantages in terms of providing easiness of application. Therefore various measures should be taken for improving the biocompatibility of dentin bonding systems