Statement of problem: Adhesive failure between the liner and the denture base creates an environment for potential bacterial growth and accelerated breakdown of the soft liner resulting in a deteriorating prosthesis.
Purpose: This study evaluated the effects of a specific sandblasted or lased preparation on the interfacial bonding of polymethyl methacrylate and silicone and polyethyl methacrylate resilient liners.
Material and methods: Polymethyl methacrylate test specimens were fabricated and received one of three surface treatments: untreated (control), sandblasted (250 microns aluminum oxide particles), and lased (carbon dioxide). Polyethyl methacrylate and silicone resilient lining materials were applied to these surfaces and the peel strengths were determined with the American Society for Testing and Materials peelin-adhesion test.
Results: Altering the polymethyl methacrylate surface by sandblasting significantly reduced the peel strengths for the polymethyl methacrylate/polyethyl methacrylate and polymethyl methacrylate/silicone specimens. Altering the polymethyl methacrylate surface by delivering carbon dioxide laser energy to form a grid pattern produced lower peel strengths that were statistically significant from the controls for the polymethyl methacrylate/polyethyl methacrylate specimens, but not so for the polymethyl methacrylate/silicone specimens. Untreated polymethyl methacrylate/polyethyl methacrylate peel strengths were significantly higher than polymethyl methacrylate/silicone.
Conclusions: Results of this study imply that mechanical surface preparation of denture bases before application of a resilient liner may not be warranted.