Cytotoxicity of Temporary Filling Materials on Three-dimensional Pulp-derived Cell Cultures

The temporary filling materials in Thailand are mainly imported and expensive, thus we had produced the materials at Faculty of Dentistry, Mahidol University. We hope that the materials will distribute to dental product markets.

Objectives: To evaluate and compare the cytotoxicity of four temporary filling materials; our temporary filling materials (2 formulae: Code 16 and 21), and 2 commercial products (Caviton and Fermin) on three-dimensional (3-D) pulp-derived cell cultures in perfusion condition through the dentine barrier models.

Methods: Bovine pulp-derived cells transfected with simian virus 40 Large T-antigen were grown 3-D on polyamide meshes. Then, the 3-D cell cultures were placed in pulpal part of dentine barrier models. Each material was also applied on bovine dentine disk in a perfusion chamber. After 24 hr exposure with the materials in perfusion condition, cell survival was evaluated using MTT assay. Cell viability of the experimental groups were expressed in percentage of the control which no test material was applied on the dentine.

Results: Mean percentages of cell viability of the experimental materials (formula 16 and 21,Caviton and Fermin)were 89.763±9.752, 102.688±26.282, 91.333±12.839 and 102.066±19.884, respectively. The results indicated that our material “Formula 16” and “Caviton” were mildly cytotoxic while “Formula 21” and “Fermin” were non-cytotoxic. They were acceptable in accordance with a requirement of ISO (the International Organization for Standardization). The statistic analysis showed no significant difference between the experimental materials (p>0.05).

Conclusions: It was concluded that the commercial and our temporary filling materials had mild or non-cytotoxicity and acceptability. This in vitro experimental model, which simulates the pulp environment, is useful for studying the toxicity effects of dental materials before clinical use.