The European journal of prosthodontics and restorative dentistry

Bonding of silicone extra-oral elastomers to acrylic resin: the effect of primer composition.

PMID 14562648


Silicone elastomer is bonded to acrylic resin in many facial or oro-facial prostheses. The silicone elastomer/acrylic resin bond has been reported to be insufficient and primers have been used to enhance the bond. This study investigated the bond strength of silicone elastomer to acrylic resin using different types of primers. The extra-oral silicone elastomers studied were Cosmesil and Ideal. The "overlap-joint" model was used to evaluate the bond strength and the samples were stretched until fracture. The bonding surfaces were treated with a primer. The control primer was Cosmesil and the others a mixture of Cosmesil/Z-6020 and Cosmesil/A-174 in 50/50 v/v ratio. The bond strength ranged from 0.026 MPa to 0.219 MPa. The results obtained in this work led to the conclusion that the most critical parameter allowing the efficient performance of a primer is the compatibility and affinity of its composition with the selected silicone elastomer.