title: Effect of cigarette smoke on color stability and surface roughness of dental composites.
abstract: OBJECTIVE
  To evaluate the color stability and surface roughness of 3 dental composites subjected to cigarette smoke and brushing.
  
  
  METHODS
  Twenty specimens were prepared for each type of restorative material used: nanohybrid (Tetric N-Ceram); hybrid (Z250-3M ESPE) and silorane-based microhybrid (Filtek P90-3M ESPE), which were divided into 2 groups (n=10), according to the type of finishing/polishing received: Group 1 - papers with decreasing abrasive grit and Group 2 - polyester matrix (without polishing). After initial readouts of color (Easy Shade-VITA) and surface roughness (SJ-201P Mitutoyo), specimens were subjected to action of smoke from 20 cigarettes, (Marlboro Red-Philip Morris). After each cigarette, the samples were submitted to brushing in a standardised device. After this, final readouts were taken to calculate change in color (ΔE and ΔL) and roughness (ΔRa), which were statistically analysed (2-way ANOVA, Bonferroni, and Student's-t tests respectively, p<0.05).
  
  
  RESULTS
  Tetric N-Ceram presented color change at clinically unacceptable levels (ΔE>3.3) when the polyester strip was used for finishing, a result differing (p<0.05) from those of the other composites, which presented no difference between them (p>0.05). Unpolished composites presented higher Ra values than those that were polished (p<0.05), with exception of the silorane based composite.
  
  
  CONCLUSIONS
  Absence of polishing increases cigarette capacity to stain composites and surface roughness of composites, with exception of the silorane based type.
authors.affiliation: Department of Dental Materials and Prosthodontics. Ribeirão Preto School of Dentistry-University of São Paulo, Brazil.
authors.forename: C C
authors.initials: CC
authors.lastname: Alandia-Roman
authors.forename: D R
authors.initials: DR
authors.lastname: Cruvinel
authors.forename: A B S
authors.initials: AB
authors.lastname: Sousa
authors.forename: F C P
authors.initials: FC
authors.lastname: Pires-de-Souza
authors.forename: H
authors.initials: H
authors.lastname: Panzeri
mesh_terms: D000465:Algorithms; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003116:Color; D003188:Composite Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing / Q000379:methods; D008689:Methacrylates / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry; D011091:Polyesters / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D062047:Silorane Resins / Q000737:chemistry; D012906:Smoke; D013499:Surface Properties; D014026:Nicotiana; D014099:Toothbrushing / Q000295:instrumentation
chemical_list: D003188:Composite Resins; D003764:Dental Materials; C444701:Filtek Z250; D008689:Methacrylates; D011091:Polyesters; D011109:Polymethacrylic Acids; D011140:Polyurethanes; D062047:Silorane Resins; D012906:Smoke; C544925:filtek P90; C029824:urethane dimethacrylate luting resin; C020946:triethylene glycol dimethacrylate; C041979:2,2-bis-(4-(2-methacryloxyethoxy)phenyl)propane; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate