Some variables influencing the bond strength between PMMA and a silicone denture lining material.
OBJECTIVE
The purpose of the present study was to investigate the effect of roughening the denture base surface on the tensile and shear bond strengths of a poly(dimethylsiloxane) resilient lining material (Molloplast-B) bonded to a heat-cured acrylic resin denture base material. These measured bond strengths were compared to those obtained by packing the soft lining material against poly(methyl methacrylate) (PMMA) denture base acrylic resin dough.


METHODS
Three groups of 10 specimens each were constructed for both tensile and shear tests. In the first group, Molloplast-B was packed against cured PMMA denture base surface. In the second group, Molloplast-B was packed against cured PMMA denture base whose surface had been roughened with an acrylic bur. In a third group, Molloplast-B was packed against PMMA denture base acrylic resin dough.


RESULTS
Molloplast-B exhibited significantly higher tensile and shear bond strengths when packed against acrylic resin dough. Roughening the denture base surface prior to the application of Molloplast-B had a statistically significant weakening effect on tensile bond strength compared with the smooth surface and the acrylic resin dough. For the shear bond strength, roughening the surface produced a nonsignificant increase compared with the smooth surface, but the bond was weaker than when packed against acrylic resin dough.


CONCLUSIONS
Significant differences in tensile and shear bond strength were recorded between the three methods used to bond Molloplast-B to denture base material.
Jagger
Robert G
RG
University of Wales College of Medicine, Dental School, Cardiff, United Kingdom.
al-Athel
Moodhy S
MS
Jagger
Daryll C
DC
Vowles
Richard W
RW
D000704:Analysis of Variance; D001672:Biocompatible Materials; D001840:Dental Bonding; D003819:Denture Bases; D003822:Denture Liners; D004129:Dimethylpolysiloxanes; D008422:Materials Testing; D019904:Polymethyl Methacrylate; D012826:Silicone Elastomers; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength
D001672:Biocompatible Materials; D004129:Dimethylpolysiloxanes; C020964:MDX 4-4210; D012826:Silicone Elastomers; D019904:Polymethyl Methacrylate