In Vitro Cytotoxicity of Maxillofacial Silicone Elastomers: Effect of Nano-particles

Silicone elastomers are generally used for maxillofacial extraoral prostheses. The purpose of this in vitro study was to evaluate the cytotoxicity of different kinds of nanoparticles added to two types of maxillofacial elastomers.

A-2000 and A-2006 silicone elastomers were used. The silicone specimens were divided into eight groups according to the presence of additional nanoparticles (n = 18). The following represents the groups in the study: Group A: A-2000 silicone (control group); Group B: A-2006 silicone (control group); Group C: A-2000 silicone and the addition of titanium dioxide (TiO₂ ); Group D: A-2006 silicone and the addition of TiO₂ ; Group E: A-2000 silicone and the addition of fumed silica; Group F: A-2006 silicone and the addition of fumed silica; Group G: A-2000 silicone and the addition of silaned silica; Group H: A-2006 silicone and the addition of silaned silica. A paired sample t-test was used to analyze the cytotoxicity of each group after 24, 48, and 72 hours.

Based on the results of the 24-hour analysis, the biocompatibility values of the (A-2006) fumed silica group were higher than those of the control groups. There was no statistically significant difference in A-2006 and A-2000 groups. The cytotoxicity values of the control groups and TiO₂ (A-2000 silicone) elastomer groups increased at all test times; however, the cytotoxicity values of the TiO₂ (A-2006), fumed silica (A-2006), silaned silica (A-2006), fumed silica (A-2000), and silaned silica (A-2000) groups increased significantly only from 24 to 48 hours.

Nanoparticles of TiO₂ , fumed silica, and silaned silica added to a commercial silicone-based elastomer used for fabrication of maxillofacial prostheses are nontoxic.