Cytotoxicity, chlorhexidine and residual monomer release from heat- polymerized denture base resin modified by polyethylene glycol (PEG)and chlorhexidine (CHX).

Background: Antibacterial surfaces can function by either inhibiting the adhesion of bacteria or killing the bacteria on the surface or a combination of both.Aims: This study aims to modify denture base resin by blending (PEG), and incorporation of (CHX) in different concentrations to evaluate the cytotoxic potential, and to estimate the amount of CHX and residual monomer release.Materials and methods: Samples were prepared from (Triplex heat polymerized denture base resin), the experimental groups incorporated with 10%, 15% and 20% concentrations of PEG polymer and 156, 312, 625 l/10 ml of monomer concentrations of CHX and mix of both.The cytotoxicity of the samples evaluated by MTT assay for the highest concentration groups.The amount of residual monomer and chlorohexidine release in 1 st , 2 nd , .., 7 th , 14 th , 21 st , and 28 th days evaluated by using UV-Vis spectrophotometer.Results: The MTT assay results revealed no cytotoxic effect on mouse fibroblast L-929 cells.The values of residual monomer elution was higher in the first day then decreased with time till 28 th day, and the amount of monomer released for experimental groups blended with PEG, decreased with comparison to that of the control at p 0.05.The CHX released from experimental group was higher in the first day then decreased with time till 28 th day, the amount of released CHX increased with increased concentration of incorporation of CHX at p 0.05, and the CHX release of the experimental groups incorporated with PEG is still continued at 28 th day.Conclusion: Modified denture base resin with PEG and CHX had no cytotoxic effect.Blending of PEG decrease residual monomer release and increase the period of CHX elusion.