title: Effect of surface treatments on the bond strength of soft denture lining materials to an acrylic resin denture base.
abstract: BACKGROUND
  Adhesive failure between acrylic resin and resilient liner material is commonly encountered in clinical practice.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the effect of different surface treatments on the bond strength of 2 different resilient lining materials to an acrylic resin denture base.
  
  
  METHODS
  Ninety-six dumbbell-shaped specimens were fabricated from heat-polymerized acrylic resin, and 3 mm of the material was cut from the thin midsection. The specimens were divided into 6 groups according to their surface treatments: no surface treatment (control group), 36% phosphoric acid etching (acid group), erbium:yttrium-aluminum-garnet (Er:YAG) laser (laser group), airborne-particle abrasion with 50-μm Al2O3 particles (abrasion group), an acid+laser group, and an abrasion+laser group. The specimens in each group were divided into 2 subgroups according to the resilient lining material used: heat-polymerized silicone based resilient liner (Molloplast B) and autopolymerized silicone-based resilient liner (Ufi Gel P). After all of the specimens had been polymerized, they were stored in distilled water at 37°C for 1 week. A tensile bond strength test was then performed. Data were analyzed with a 2-way ANOVA, and the Sidak multiple comparison test was used to identify significant differences (α=.05). The effects of the surface treatments and resilient lining materials on the surface of the denture base resin were examined with scanning electron microscopy.
  
  
  RESULTS
  The tensile bond strength was significantly different between Molloplast B and Ufi Gel P (P<.001). The specimens of the acid group had the highest tensile bond strength, whereas those of the abrasion group had the lowest tensile bond strength. The scanning electron microscopy observations showed that the application of surface treatments modified the surface of the denture base resin.
  
  
  CONCLUSIONS
  Molloplast B exhibited significantly higher bond strength than Ufi Gel P. Altering the surface of the acrylic resin denture base with 36% phosphoric acid etching increased bond strength.
authors.affiliation: Research Assistant, Department of Prosthodontics, Faculty of Dentistry, Atatürk University, Erzurum, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Gundogdu
authors.affiliation: Professor, Department of Prosthodontics, Faculty of Dentistry, Recep Tayyip Erdoğan University, Rize, Turkey. Electronic address: zyesilz@hotmail.com.
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Yesil Duymus
authors.affiliation: Research Assistant, Department of Prosthodontics, Faculty of Dentistry, Atatürk University, Erzurum, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Alkurt
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000180:Acrylic Resins / Q000737:chemistry*; D000537:Aluminum Oxide / Q000737:chemistry; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D003764:Dental Materials / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D003819:Denture Bases; D003822:Denture Liners; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D006801:Humans; D053844:Lasers, Solid-State; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010756:Phosphoric Acids / Q000737:chemistry; D058105:Polymerization; D012826:Silicone Elastomers / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D003764:Dental Materials; D004129:Dimethylpolysiloxanes; C020964:MDX 4-4210; D010756:Phosphoric Acids; C488492:QC 20 (denture base resin); D012826:Silicone Elastomers; C483158:Ufi gel; D014867:Water; C030242:phosphoric acid; D000537:Aluminum Oxide