title: Weight loss and changes in surface roughness of denture base and reline materials after simulated toothbrushing in vitro.
abstract: OBJECTIVE
  To evaluate the weight loss and the surface roughness of acrylic resins after simulated brushing tests.
  
  
  METHODS
  Ten specimens of each material (Tokuyama Rebase II-TR, New Truliner-NT, Ufi Gel Hard-UH and Lucitone 550-L) were made. The wear loss (mg) by weight and the surface roughness (Ra μm) of each specimen was determined before and after brushing. The specimens were placed on the brushing machine and a total of 20,000 brushing cycles was performed. The results of weight loss and roughness values were submitted to the anova followed by the Tukey's test (p = 0.05).
  
  
  RESULTS
  The mean weight loss of material L was statistically higher (p < 0.001) than that of the relines TR, UH and NT. No significant differences were found among the roughness values of resins TR, UH and L (p > 0.05). Only for L, toothbrushing increased the surface roughness. After toothbrushing, there was no significant difference between the roughness values of materials L and NT. The highest mean weight loss during the simulated toothbrushing tests was observed for L. Before the toothbrushing tests, the NT exhibited the highest mean roughness.
  
  
  CONCLUSIONS
  Brushing resulted in increase in roughness only for resin L.
authors.affiliation: Department of Dental Materials and Prosthodontics, Araraquara Dental School, UNESP, Universidade Estadual Paulista, Araraquara, São Paulo, Brazil. cucci@foar.unesp.br
authors.forename: Ana Lucia
authors.initials: AL
authors.lastname: Machado
authors.forename: Eunice Teresinha
authors.initials: ET
authors.lastname: Giampaolo
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: Vergani
authors.forename: Ana Cláudia
authors.initials: AC
authors.lastname: Pavarina
authors.forename: Débora da Silva Lopes
authors.initials: Dda S
authors.lastname: Salles
authors.forename: Janaina Habib
authors.initials: JH
authors.lastname: Jorge
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D019554:Dental Restoration Wear; D003819:Denture Bases; D003822:Denture Liners; D003823:Denture Rebasing; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D020366:Methylmethacrylate / Q000737:chemistry; D008768:Methylmethacrylates / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry; D012826:Silicone Elastomers / Q000737:chemistry; D013499:Surface Properties; D014099:Toothbrushing / Q000379:methods*
chemical_list: D000180:Acrylic Resins; D003764:Dental Materials; D008689:Methacrylates; D008768:Methylmethacrylates; D012826:Silicone Elastomers; C483158:Ufi gel; C514244:tokuyama rebase fast II; C071514:truliner; D020366:Methylmethacrylate; C040291:Lucitone; C004919:ethylene dimethacrylate; C009931:poly(ethylmethacrylate); D019904:Polymethyl Methacrylate