The term «resin-based dental materials» refers to dental materials containing polymers. Usually, these polymers are formed by in situ polymerization of methacrylate monomers. The polymerization process never reaches completion, and unreacted monomers can leak out after curing. The availability of data concerning patient side effects caused by leakage products is sparse, but side effects linked to these materials have been reported. Allergic reactions to resin-based materials in dental personnel strongly indicates that monomers bind to proteins in the human body. Detailed knowledge of the possible toxicity of the leakage products and underlying mechanisms is, however, mainly based on methacrylate-exposure studies using cultured cells. In these in vitro studies, methacrylates are shown to have a cytotoxic potential. Both cell death and inhibition of cell growth was observed in a variety of cell lines. Based on several other findings it has been suggested that these responses are caused by oxidative stress and DNA damage in cells exposed to methacrylates. Not all studies support this view, and other mechanisms such as direct interaction with proteins is also suggested as key events. Although in vitro experiments can provide valuable information on the potential of possible toxicants to interfere with cellular molecules, homologous cell cultures lack the complexity of multicellular mechanisms. Furthermore, cells in a culture differ from their in vivo counterparts, e.g. by altered expression of certain metabolic enzymes. Hence, a translation to an in vivo situation is associated with great uncertainty and should be done with caution.
Toxicity of plast materials
Samuelsen JT, Dahl JE.
Aktuel nordisk odontologi, Universitetsforlaget, 01/2016: 185-194