Review of the biological response to a novel bone cement containing poly(ethyl methacrylate) and n-butyl methacrylate.

This review describes work published independently elsewhere in which the biological reactions to poly(ethyl methacrylate) n-butyl methacrylate (PEMBMA) have been studied. This material has been compared throughout with conventional poly(methyl methacrylate) (PMMA). Butyl methacrylate monomer used in PEMBMA was slightly less toxic than methyl methacrylate monomer used in PMMA when injected intraperitoneally in mice. No differences in cardiorespiratory effects were found between n-butyl and methyl monomer infused intravenously into anaesthetized rabbits. The tissue reaction to the beaded polymers of poly(methyl methacrylate) and poly(ethyl methacrylate) implanted subcutaneously was identical. The surface appearance of the two materials differed significantly when viewed by scanning electron microscopy, showing a series of elevations resembling tightly packed spheres in the case of PMMA, but a smooth surface with only occasional smooth elevations in the case of PEMBMA. Intramuscular implantation showed more fibrous tissue and tissue damage in relation to PMMA cured in situ compared with PEMBMA and there was more bone necrosis and a thicker fibrous tissue layer adjacent to PMMA than PEMBMA when cured intraosseously.