Microtensile Bond Strength of Resin-Resin Interfaces After 24-Hour and 12-Month Soaking
Evaluate the bond strengths of denture base-repair materials to minimize recurrent failure rate. Use microtensile bond strength (μTBS) testing to evaluate the interfacial bonding strength of 6 commercial denture repair materials after 24-hour and 12-month soaking. Blocks of poly(methyl metacrylate) (PMMA) and Triad were fabricated, fractured, and repaired. Twenty bars (1 × 1 × 30 mm) per group were sectioned from each block parallel to the long axis and ∼90° to the resin-resin repair interface and stored before μTBS testing in a servo-hydraulic tensile-testing machine. Intact PMMA and Triad bars that had been soaked for 24 hours and 12 months were tested for reference. The 24-hour repair strengths for PMMA ranged from 52% to 84% of original strength. Soaking for 12 months resulted in a 20% decrease in strength for the PMMA control. The 12-month repair strengths for PMMA ranged from 43% to 74% of the 12-month soaked material strength. Triad repair tested 35% of original strength after soaking for 24 hours. Permabond (cyanoacrylate) to PMMA tested 47% of original strength after 24 hours of soaking and 26% of the 12-month soaked material strength. Permabond to Triad tested 30% of original strength after 24 hours of soaking. Permabond and Triad showed a 100% adhesive mode of failure. All other materials tested exhibited either an adhesive mode of failure at the denture base-repair-material interface or a complex cohesive failure within the repair-material interface. The μTBS approach can be used to analyze the resin-resin interface of repaired acrylics. The relatively small standard deviations make the μTBS approach attractive. In this study, μTBS was used to evaluate the repair strength of 6 denture repair materials enabling clinicians to make clinical judgments regarding the strongest repair bond available.Abstract
Contributor Notes
Curry Leavitt, is a senior dental student at Temple University School of Dentistry.
Kenneth G. Boberick, DMD, is an associate professor of restorative dentistry at Temple University School of Dentistry, 3223 North Broad Street, Philadelphia, PA 19140. Address correspondence to Dr. Boberick (KBoberick@dental.temple.edu).
Sheldon Winkler, DDS, is an adjunct professor of dentistry at the College of Dental Medicine, Midwestern University, Glendale, Arizona. He formerly served as professor and chairman of the Department of Prosthodontics at Temple University School of Dentistry.