Cytotoxic effects to mouse and human gingival fibroblasts of a nanohybrid ormocer versus dimethacrylate-based composites.

OBJECTIVES: Tooth-colored composites have emerged as a standard restorative material in caries therapy and have largely replaced materials such as silver amalgam or glass ionomer cements. In addition to their superior esthetics and desirable mechanical properties, composites also comprise negative characteristics, such as wear, shrinkage, and an adverse biocompatibility. Modifications of classic resin-based dental composites have been developed to overcome these shortcomings. For example, ormocers are innovative inorganic-organic hybrid polymers that form a siloxane network modified by the incorporation of organic groups. Recently, a new ormocer, Admira Fusion (VOCO), was introduced to composite technology. The absence of cytotoxic matrix monomers leads to the hypothesis that ormocers have improved biocompatibility compared to resin-based dental restorative materials. MATERIALS AND METHODS: The aim of this study was to compare the cytotoxic effects of Admira Fusion to a nanohybrid composite (GrandioSO, VOCO) and a nanofiller composite (Filtek Supreme XTE, 3M Espe) on the standard dermal mouse fibroblasts (L929) and human gingival fibroblasts (GF-1) via a Cell Counting Kit-8 (CCK-8) assay. RESULTS: Admira Fusion was significantly less cytotoxic than GrandioSO and Filtek Supreme XTE to both the standard mouse dermal fibroblasts (L929) and human gingival fibroblasts. CONCLUSIONS: Compared to other resin-based dental restorative materials, the ormocer (Admira Fusion) possesses a superior biocompatibility in vitro. Future research studies are needed to confirm our results. CLINICAL SIGNIFICANCE: Clinically, dental practitioners and their patients might benefit from Admira Fusion in terms of reduced adverse biologic reactions compared to resin-based dental restorative materials.

Correlation of elution and sensitivity of cell lines to dental composites.

OBJECTIVES: The aim of the present study was to understand the role played by composition on the elution of dental composites and the subsequent cytotoxicity, the sensitivity of different cell lines to eluates on a temporal basis and the correlation of the two parameters elution and cytotoxicity. METHODS: LC-MS was done to analyze the eluates. MTT assay was done to assess cytotoxicity on two cell lines. RESULTS: Eluates were found to have matrix monomers, photoinitiators and their degradation products. The short-term viability of other mammalian cell line was inferior to human cell line. However human cell line became more sensitive to long-term incubation with composites. There was a strong inverse correlation to elution of monomers and photoinitiators and cell viability for both cell lines. Bisphenol A elution did not correlate to cell viability. SIGNIFICANCE: Other mammalian cell lines may be more sensitive to acute toxin build-up than human cell line while the latter may be more sensitive to prolonged toxin exposure. Dimethacrylate based composites elute more and exert strong cytotoxicity than Ormocer and Silorane based composites. Most of the eluates correlated linearly to cytotoxicity.