title: Initial polishing time affects gloss retention in resin composites.
abstract: OBJECTIVE
  To determine the effect of finishing and polishing time on the surface gloss of various resin-composites before and after simulated toothbrushing.
  
  
  METHODS
  Eight representative resin-composites (Ceram X mono, Ceram X duo, Tetric EvoCeram, Venus Diamond, EsteliteSigma Quick, Esthet.X HD, Filtek Supreme XT and Spectrum TPH) were used to prepare 80 disc-shaped (12 mm x 2 mm) specimens. The two step system Venus Supra was used for polishing the specimens for 3 minutes (Group A) and 10 minutes (Group B). All specimens were subjected to 16,000 cycles of simulated toothbrushing. The surface gloss was measured after polishing and after brushing using the gloss meter. Results were evaluated using one way ANOVA, two ways ANOVA and Dennett's post hoc test (P = 0.05).
  
  
  RESULTS
  Group B (10-minute polishing) resulted in higher gloss values (GV) for all specimens compared to Group A (3 minutes). Also Group B showed better gloss retention compared to Group A after simulated toothbrushing. In each group, there was a significant difference between the polished composite resins (P < 0.05). For all specimens there was a decrease in gloss after the simulated toothbrushing.
authors.affiliation: School of Dentistry, University of Manchester, Manchester, United Kingdom. drnouni@yahoo.com
authors.forename: Nehal
authors.initials: N
authors.lastname: Waheeb
authors.forename: Nick
authors.initials: N
authors.lastname: Silikas
authors.forename: David
authors.initials: D
authors.lastname: Watts
mesh_terms: D012117:Resins, Synthetic
chemical_list: D012117:Resins, Synthetic