In Vitro Cytotoxicity of Linseed Oil as Bio-Based Plasticiser in Polymethylmethacrylate (PMMA) Denture Base Material

Abstract

Objectives: Polymethyl methacrylate (PMMA) is a polymer that is vastly utilised as denture base material. Previously synthetic plasticiser like Dibutyl phthalate was previously used in the PMMA. However, there are reports of ester leaching causing intraoral toxicity. Thus, bringing the awareness about organic plasticiser usage, like linseed oil. This study aims to evaluate the cytotoxicity of linseed oil to ensure its safety to be used as the natural-based plasticiser in PMMA as denture base material. Materials and Methods: The cytotoxicity of linseed oil was evaluated by culturing Human Gingival Fibroblast cells with 1, 3, 5, 7, and 10% linseed oil for 24, 48, and 72 hours. The WST-1 assay was then used to evaluate cell viability, with cell quantification performed using a spectrophotometer at a wavelength range of 420-480nm. An unpaired t-test was used to analyse all parameters' quantitative cell viability data. Results: The WST-1 Assay demonstrated that linseed oil exhibited greater than 95% cell viability at all doses and incubation durations, indicating biocompatibility. At 72 hours of incubation, there are statistically significant differences between the cells incubated in the Linseed Oil as compared to Dimethyl Sulfoxide (DMSO), which acts as a positive control. Conclusions: The study proves that linseed oil is non-cytotoxic with the Human Gingival Fibroblast cells and safe to use when incorporated later in the PMMA as denture base material.