The Cytotoxicity of Dental Restorative Materials on Gingival Stromal Mesenchymal Cells-an In Vitro Study.

Background: Due to their minimally invasive high-quality adhesive, aesthetic and mechanical qualities, composite resins are the most frequently used materials in modern restorative dentistry. However, polymerization shrinkage and cytotoxicity are still unresolved drawbacks associated with these biomaterials.

Purpose: The present study aimed to assess the cytotoxicity of some restorative resin-based materials on gingival mesenchymal stromal cells (gMSCs), assuming that no differences in their behavior will be highlighted.

Material and methods: The cytotoxicity of the tested materials was evaluated by comparing the behavior of gMSCs cultured in normal conditions and in association with disc-shaped material samples indirectly through functionality tests (colony-forming unit-fibroblast assay, migratory potential) and directly through the MTT assay. The results were statistically analyzed with the ANOVA test and Tukey's Honest Significant Difference test.

Results: According to the MTT assay, there are no statistically significant differences regarding the viability of gMSCs cultured in normal conditions or in the presence of resin-based material samples. On the other hand, the present study identified a significantly reduced number of colonies formed by the gMSCs cultured in association with BF and B discs, compared to that of gMSCs cultured in normal conditions. Also, the migratory potential was significantly lower for control gMSCs when compared to ZE-gMSCs and significantly higher for ZE-gMSCs when compared to BF-gMSCs or BFL-gMSCs.

Conclusions: The results of the present study highlight a possible risk of cytotoxicity when using resin based-materials in dental practice, but they cannot be directly extrapolated to in vivo situations.