title: Influence of organic acids present in oral biofilm on the durability of the repair bond strength, sorption and solubility of resin composites.
abstract: OBJECTIVE
  To evaluate the repair bond strength after storage in water, lactic and propionic acid after 7 days and 6 months and the sorption and solubility of resin composites used.
  
  
  METHODS
  Five cylinders of each resin composite (microhybrid, nanofilled and silorane-based composite) were prepared. Specimens were aged with thermocycling (5 and 55°C) 5,000 times. A repair procedure was performed using intraoral sandblasting with 50-µm aluminum oxide, application of an adhesive system and cylinder of composite was fabricated. Specimens were sectioned into beams and stored in three immersion media: water, propionic acid and lactic acid. The microtensile bond strength was measured after periods of 7 days and 6 months. Sorption and solubility were evaluated using 15 specimens (0 = 6 mm; h = 1 mm) of each resin composite, which were prepared and assigned into three groups (n = 5) according to the immersion media (water, propionic acid and lactic acid). Data were analyzed using one-way/two-way/three-way ANOVA and Tukey's test (α = 0.05).
  
  
  RESULTS
  The resin composites, immersion media and time of immersion did not affect the repair bond strength (microhybrid 38.3 to 40.9 MPa; nanofilled 38.7 to 42.2 MPa; silorane 41.2 to 51.1 MPa). Additionally, the immersion media did not affect the sorption and solubility. The silorane-based composite presented the lowest sorption (10.5 to 12.1 µg/mm3) and solubility (-2.4 to -2.7 µg/mm3), while the nanofilled methacrylate-based composite showed the highest sorption (32.1 to 33.6 µg/mm3). Regarding solubility, the nanofilled and microhybrid methacrylate-based composites did not present statistically significant differences.
authors: Stephane
authors: S
authors: Da Silva
authors: Eduardo Moreira
authors: EM
authors: Da Silva
authors: Marcella Bruna Ferreira
authors: MB
authors: Delphim
authors: Laiza Tatiana
authors: LT
authors: Poskus
authors: Cristiane Mariote
authors: CM
authors: Amaral
mesh_terms: D065966:Absorption, Physicochemical; D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry; D018441:Biofilms; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D003764:Dental Materials / Q000737:chemistry*; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry*; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry; D011422:Propionates / Q000737:chemistry*; D062047:Silorane Resins / Q000737:chemistry; D012995:Solubility; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D008689:Methacrylates; D011422:Propionates; D062047:Silorane Resins; D014867:Water; D019344:Lactic Acid; D017438:Bisphenol A-Glycidyl Methacrylate; C029658:propionic acid; D000537:Aluminum Oxide