title: Influence of methyl mercaptan on the repair bond strength of composites fabricated using self-etch adhesives.
abstract: The influence of methyl mercaptan on the repair bond strength of composites fabricated using self-etch adhesives was investigated. The surface free-energies were determined by measuring the contact angles of test liquids placed on composites that had been immersed in different concentrations of methyl mercaptan (0.01, 0.1, and 1.0 M). To determine the repair bond strength, self-etch adhesives were applied to the aged composite, and then newly added composites were condensed. Ten samples of each specimen were subjected to shear testing at a crosshead speed of 1.0 mm min(-1). Samples were analyzed using two-way ANOVA followed by Tukey's honestly significant difference (HSD) test. Although the dispersion force of the composites remained relatively constant, their polar force increased slightly as the concentration of methyl mercaptan increased. The hydrogen-bonding forces were significantly higher after immersion in 1.0 M methyl mercaptan, leading to higher surface-free energies. However, the repair bond strengths for the repair restorations prepared from composites immersed in 1.0 M methyl mercaptan were significantly lower than for those immersed in 0.01 and 0.10 M methyl mercaptan. Considering the results of this study, it can be concluded that the repair bond strengths of both the aged and newly added composites were affected by immersion in methyl mercaptan solutions.
authors.affiliation: Department of Operative Dentistry, Nihon University School of Dentistry, Tokyo, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Yokokawa
authors.forename: Akitomo
authors.initials: A
authors.lastname: Rikuta
authors.forename: Akimasa
authors.initials: A
authors.lastname: Tsujimoto
authors.forename: Kenji
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Syo
authors.initials: S
authors.lastname: Shibasaki
authors.forename: Saki
authors.initials: S
authors.lastname: Matsuyoshi
authors.forename: Masashi
authors.initials: M
authors.lastname: Miyazaki
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003764:Dental Materials / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D006801:Humans; D006847:Hydrocarbons, Iodinated / Q000737:chemistry; D006860:Hydrogen Bonding; D007101:Immersion; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D009281:Naphthalenes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013314:Stress, Mechanical; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties; D013500:Surface Tension; D014867:Water / Q000737:chemistry; D017155:Wettability
chemical_list: C470433:Beautifil composite resin; C000601955:Bond Force dental cement; D003188:Composite Resins; D003764:Dental Materials; C507124:Estelite sigma; D006847:Hydrocarbons, Iodinated; D009281:Naphthalenes; D019279:Resin Cements; D013438:Sulfhydryl Compounds; C584662:beautibond; D014867:Water; C031721:naphthalene; C005231:methylmercaptan; C027946:methylene iodide; D017438:Bisphenol A-Glycidyl Methacrylate
keywords: light-cured composite; methyl mercaptan; repair bond strength; repair restoration; surface free-energy