title: The effect of toothbrushing on surface gloss of resin composites.
abstract: OBJECTIVE
  To determine the changes in surface gloss of different composite materials after laboratory toothbrushing simulation.
  
  
  METHODS
  36 specimens were fabricated for each material and polished with 120-, 220-, 500-, 1200-, 2400- and 4000-grit SiC abrasive paper, respectively. Gloss measurements were made with a glossmeter (Novocurve) prior to testing procedures and then subjected to simulated toothbrushing for 5, 15, 30 and 60 minutes by means of an electric toothbrush with a pressure of 2N while being immersed in a 50 RDA toothpaste slurry. Four supplementary samples per group were analyzed under SEM immediately after polishing procedures and four samples after 60 minutes simulated toothbrushing in order to evaluate the causes of the gloss decrease. The tested resin composite materials were Filtek Supreme XTE, Durafill, HRi Enamel Plus, Miris 2, Empress Direct, Venus Diamond, Gradia Direct, Clearfil Photo Posterior and G-aenial. Natural enamel represented the control group. Statistical analysis was performed using Kruskal Wallis and Tukey post-hoc test, with a level of significance set at 0.05.
  
  
  RESULTS
  Resin composite initial gloss values ranged from 68.9 to 100.5 at baseline to 10.6 to 62.6 after 1 hour of brushing. Highest gloss values were obtained by Filtek Supreme XTE, followed by Empress Direct and Durafill. Lowest values were obtained by Clearfil Photoposterior, Miris 2, Enamel HRi and Venus Diamond. Natural enamel was the only substrate to maintain its gloss throughout the brushing procedure (110.4 after 60 minutes). SEM analysis revealed different patterns of surface degradation depending on the composite material.
authors.affiliation: Division of Cariology & Endodontology, Dental School, University of Geneva, Geneva, Switzerland. Dorien.Lefever@unige.ch
authors.forename: Dorien
authors.initials: D
authors.lastname: Lefever
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Perakis
authors.forename: Miguel
authors.initials: M
authors.lastname: Roig
authors.forename: Ivo
authors.initials: I
authors.lastname: Krejci
authors.forename: Stefano
authors.initials: S
authors.lastname: Ardu
mesh_terms: D017609:Barium Compounds / Q000737:chemistry; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003743:Dental Enamel / Q000033:anatomy & histology; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing / Q000379:methods; D005459:Fluorides / Q000737:chemistry; D005898:Glass / Q000737:chemistry; D006801:Humans; D007811:Lanthanum / Q000737:chemistry; D008027:Light; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D012824:Silicic Acid / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013324:Strontium / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors; D014099:Toothbrushing / Q000295:instrumentation / Q000379:methods*; D014100:Toothpastes / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry
chemical_list: D017609:Barium Compounds; D017554:Carbon Compounds, Inorganic; D003188:Composite Resins; D003764:Dental Materials; C474035:Filtek Supreme; C470230:Gradia; D017655:Silicon Compounds; D014100:Toothpastes; C488393:Venus (composite resin); C102738:barium glass filler; C092420:Clearfil Photo Posterior; D012824:Silicic Acid; C083668:lanthanum trifluoride; C004832:hexafluorosilicate; D007811:Lanthanum; D012822:Silicon Dioxide; C039734:Durafill; D015040:Zirconium; D005459:Fluorides; C028541:zirconium oxide; C022088:silicon carbide; D013324:Strontium