A series of different methacrylate monomers (with either 1 or 2.5% dimethyl
-p-toluidine, DMPT) was gelled with poly(ethyl methacrylate) powder (contai
ning benzoyl peroxide) thus forming a room temperature curing system. When
doped with 5.625% chlorhexidine diacetate the release from the tetrahydrofu
rfuryl methacrylate-based samples was considerably greater than that from o
ther methacrylate monomers. This seems to be due to the formation of channe
ls in the polymer. Nuclear magnetic resonance spectroscopy, of solutions th
at the samples were immersed in, showed chlorhexidine was indeed being rele
ased from the polymer. It also showed that doping the polymer with chlorhex
idine hindered the polymerisation, resulting in a higher level of residual
monomer and low molecular weight components being leached from the polymer.
The DMPT also affected the polymerisation with greater leaching from the 2
.5% DMPT sample. (C) 2000 Elsevier Science Ltd. All rights reserved.