Effects of two low-shrinkage composites on dental stem cells (viability, cell damaged or apoptosis and mesenchymal markers expression).

INTRODUCTION: The cytotoxicity of dental materials has been extensively studied. Non-biocompatible or cytotoxic materials can cause short-term or long-term tissue inflammation or cell death. Regarding dental cavity filling restoratives, the most critical concern for biocompatibility is the cytotoxicity caused by the leachable components such as unreactive monomers, initiators and other additives form the organic resins or cytotoxic metal ions from the inorganic fillers. AIM: To investigate the effects of new two low-shrinkage composites SDR(®) and Venus(®)Bulk Fill on the cell viability, cellular damage and expression of mesenchymal markers on dental stem cells. METHODS: Specimens from two low-shrinkage composites were eluted with culture medium for 24 h. After 24 h of incubation, cytotoxicity of elutes were evaluated by MTT assay; apoptosis was determined using the DNA-specific fluorochrome Hoechst 33342 and the mesenchymal stem cells markers expression was analyzed by immunofluorescence staining. RESULTS: After 24 h of cell exposure to each extract media, dental stem cells expressed MSCs markers. The interaction among the material and cell line was not significantly correlated [F(1,60) = 2.251, P = 0.39], whereas statistically significant differences among cells lines were observed [F(1,60) = 9.157, P = 0.004], being dental pulp stem cells more resistant that periodontal ligament stem cells. Also, we did not find any significant effect between the tested materials [F(1,60) = 0.090, P = 0.765]. Furthermore, a very low proportion of exposed cells showed condensed or fragmented nuclei, typical of apoptotic cells at 24 h. CONCLUSIONS: The results suggest that SDR(®) and Venus(®) Bulk fill and should be considered when selecting an appropriate resin-based dental restorative material