title: Longitudinal evaluation of simulated toothbrushing on the roughness and optical stability of microfilled, microhybrid and nanofilled resin-based composites.
abstract: OBJECTIVE
  The aim of this study was to evaluate the influence of simulated toothbrushing over ten weeks on the roughness and optical stability (colour, translucency and gloss) of microfilled - Mf (Durafil VS), microhybrid - Mh (Empress Direct) and nanofilled - Nf (Z 350) resin-based composites (RBC).
  
  
  METHODS
  The roughness, colour, translucency and gloss of each RBC were measured before and after storage in distilled water (DW) and propionic acid (PA) for ten weeks. The specimens were removed from the media each week, submitted to toothbrushing simulation and the properties measured. The obtained data were analyzed using a multifactor analysis of variance (MANOVA) and Tukey's HSD test (α=0.05).
  
  
  RESULTS
  The roughness significantly increased after ten weeks for the three RBCs (p<0.05), with the final values of roughness presenting no statistical differences among them (p>0.05). Only Mf and Nf immersed in DW and Mh immersed in PA presented a change in colour after ten weeks (p<0.05), although the change in colour was lower after immersion in PA for the three RBCs (p<0.05). None of the RBCs presented significant changes in translucency after ten weeks (p>0.05). Only Mh immersed in DW presented gloss stability after ten weeks (p>0.05).
  
  
  CONCLUSIONS
  Toothbrushing increased the roughness and diminished the gloss of the three RBCs. The translucency was not influenced by the toothbrushing. The immersion in propionic acid produced lower alterations in colour than did immersion in distilled water.
  
  
  CONCLUSIONS
  In general, the three RBCs presented similar optical behaviours after toothbrushing over ten weeks. Thus, it is possible that anterior restorations produced with these materials will not present perceptible differences over time.
authors.affiliation: Analitical Laboratory of Restorative Biomaterials - LABiom-R, School of Dentistry, Federal Fluminense University, Niterói, Rio de Janeiro, Brazil. Electronic address: emsilva@vm.uff.br.
authors.forename: Eduardo Moreira
authors.initials: EM
authors.lastname: da Silva
authors.forename: Juliana
authors.initials: J
authors.lastname: Dória
authors.forename: Juliana de Jesus Rodrigues
authors.initials: Jde J
authors.lastname: da Silva
authors.forename: Guilherme Vinícius
authors.initials: GV
authors.lastname: Santos
authors.forename: José Guilherme Antunes
authors.initials: JG
authors.lastname: Guimarães
authors.forename: Laiza Tatiana
authors.initials: LT
authors.lastname: Poskus
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003116:Color; D003188:Composite Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D006801:Humans; D008027:Light; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry*; D011140:Polyurethanes / Q000737:chemistry; D011422:Propionates / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors; D014099:Toothbrushing / Q000379:methods*; D014867:Water / Q000737:chemistry
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D008689:Methacrylates; D011140:Polyurethanes; D011422:Propionates; C533204:filtek Z350; D014867:Water; C029824:urethane dimethacrylate luting resin; D017438:Bisphenol A-Glycidyl Methacrylate; C039734:Durafill; C029658:propionic acid
keywords: Optical stability; Resin-based composites; Roughness; Simulated toothbrushing