Soft prosthesis materials based on powdered elastomers.

A new class of soft prosthesis material has been developed, based on the combination of a powdered elastomer and a methacrylate monomer that polymerizes to an elastomer. Such systems are processable by conventional dental technology. This principle avoids the use of plasticizers. Natural rubber, butadiene styrene and butadiene acrylonitrile elastomers have been used, together with a number of higher alkyl methacrylates (C8-C13) and 2-ethoxyethyl methacrylate. Such systems have been evaluated with respect to mechanical properties, including tear strength, adhesion to denture base poly(methyl methacrylate), water sorption and visco-elastic properties. A number of potentially viable systems have emerged, which may be useful in external prostheses. Many have high long-term water absorption, which makes questionable their long-term usefulness interorally. Nevertheless, there is still considerable scope for development in this area.