title: Effect of brushing and accelerated ageing on color stability and surface roughness of composites.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effect of brushing and artificial accelerated ageing (AAA) on color stability and surface roughness of aesthetic restorative materials.
  
  
  METHODS
  One hundred and twenty specimens (12 mm diameter × 2 mm thick), 40 of each material (n=8) were obtained using nanosized composite Z350 (3M ESPE), nanohybrid composite Tetric N-Ceram (Ivoclar Vivadent) and ceramic IPS e.max Ceram (Ivoclar Vivadent), as control. Initial color (Spectrophotometer PCB 6807) and surface roughness (Surfcorder SE 1700) readouts were taken and the samples were separated into five groups (n=8) and treated as follows: Group 1: mechanical brushing with dentifrice RDA* 68 (Colgate), Group 2: mechanical brushing with dentifrice RDA* 180 (Colgate Total Plus Whitening), Group 3: AAA, Group 4: AAA followed by mechanical brushing with dentifrice RDA* 68 and Group 5: AAA followed by mechanical brushing with dentifrice RDA* 180. Mechanical brushing was performed for 205 min and AAA for 480 h; new color and surface roughness readouts were taken. Data were statistically analyzed (two-way ANOVA repeated measures, Bonferroni test, p<0.05).
  
  
  RESULTS
  Dentifrice abrasiveness was not significant for color change and surface roughness. When submitted to AAA+brushing, the color stability of Tetric was statistically significant (p<0.05) with both dentifrices and with dentifrice RDA* 180 for Z350. The roughness was different (p<0.05) for Z350 when brushed with RDA* 68 after AAA.
  
  
  CONCLUSIONS
  Dentifrice abrasiveness did not interfere in the ability to remove stains and roughness from aged samples. However, staining is material-dependent.
  
  
  CONCLUSIONS
  The abrasiveness of dentifrice does not change the color and surface roughness of the composites and does not help to remove surface stains from the aged samples.
authors.affiliation: Department of Dental Materials and Prosthodontics, Ribeirão Preto School of Dentistry, University of Sao Paulo, Ribeirao Preto, SP, Brazil.
authors.forename: Lourenço de Moraes Rego
authors.initials: Lde M
authors.lastname: Roselino
authors.forename: Diogo Rodrigues
authors.initials: DR
authors.lastname: Cruvinel
authors.forename: Michelle Alexandra
authors.initials: MA
authors.lastname: Chinelatti
authors.forename: Fernanda de Carvalho Panzeri
authors.initials: Fde C
authors.lastname: Pires-de-Souza
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D003116:Color; D003188:Composite Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry; D003802:Dentifrices / Q000737:chemistry; D006801:Humans; D055115:Light-Curing of Dental Adhesives / Q000379:methods; D008422:Materials Testing; D053761:Nanocomposites / Q000737:chemistry; D012824:Silicic Acid / Q000737:chemistry; D013053:Spectrophotometry / Q000295:instrumentation; D013499:Surface Properties; D013997:Time Factors; D014099:Toothbrushing / Q000295:instrumentation / Q000379:methods*; D014100:Toothpastes / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D003188:Composite Resins; D003764:Dental Materials; D003802:Dentifrices; C075815:IPS-Empress ceramic; C121818:Tetric ceram; D014100:Toothpastes; C533204:filtek Z350; C546060:hydrated silica gel-based toothpaste; D003776:Dental Porcelain; D012824:Silicic Acid
keywords: Abrasiveness; Color; Composite; Dentifrice; Surface roughness