title: Effect of bleaching and repolishing procedures on coffee and tea stain removal from three anterior composite veneering materials.
abstract: Discolored teeth can be treated with resin veneers, but their color changes when confronted with staining solutions. Polishing procedures can provide a remedy for highly stained composites, but they tend to remove some materials as well. However, bleaching procedures are an effective, nondestructive method for solving the problem. The aim of this study was to compare the color change of three veneer composites exposed to staining solutions and to evaluate the effectiveness of a 15% hydrogen peroxide bleaching agent and three polishing systems to remove the stain. Forty-five disks (12 x 2 mm) each of Clearfil ST (Kuraray Co. Ltd., Osaka, Japan), Esthet-X (Dentsply/Caulk, Milford DE, USA), and Filtek A110 (3M ESPE, St. Paul, MN, USA) were prepared. The specimens were polished with Sof-Lex (3M ESPE), Enhance (Dentsply/Caulk), or PoGo (Dentsply/Caulk). Five specimens for each material-polishing system combination were immersed in coffee (Nescafe Classic, Nestle SA, Vevey, Switzerland) or tea (Earl Grey, Lipton, Blackfriars-London, England) for 7 days. The remaining disks were stored in water. Color measurements were made with a spectrophotometer (X-Rite Seroice SP78, Loaner, Köln, Germany) at baseline; after 1, 3, 5, and 7 days; and after bleaching and repolishing. After 1 week, one side of the specimens was bleached with Illuminé-office (Dentsply De Trey GmbH, Konstanz, Germany) for 1 hour, and the other side was repolished for 30 seconds. All comparisons of color change for the polishing systems, times, and staining solutions were subjected to repeated measurements of analysis of variance. Paired t-test was used to examine whether significant color differences (deltaE*) occurred during immersion at the specified time intervals (p < or = .05). Filtek A110 was the least stained resin composite. Its color remained under a deltaE* value of 2 during the study. Clearfil ST exhibited the most color change after 1 week. All specimens polished with Enhance showed less staining, whereas those polished with the Sof-Lex system demonstrated the most color change. Water did not cause a variance in the deltaE*. There was no difference in the staining potential of coffee and tea. Bleaching and repolishing were effective in removing the stains. The resin composites tested reversed nearly to baseline color with the bleaching and to less than values at 1 day of staining with repolishing. The coffee and tea brands tested stained the composites used in this study equally. In-office bleaching was found to be more effective than repolishing in the restitution of the color.
  
  
  CONCLUSIONS
  The results of this study suggest that the discoloration of resin veneers can be partially removed by in-office bleaching and repolishing procedures.
authors.affiliation: School of Dentistry, Department of Restorative Dentistry and Endodontics, Ege University, Izmir, Turkey. sebnemturkun@hotmail.com
authors.forename: L Sebnem
authors.initials: LS
authors.lastname: Türkün
authors.forename: Murat
authors.initials: M
authors.lastname: Türkün
mesh_terms: D003069:Coffee; D003188:Composite Resins; D003775:Dental Polishing; D003801:Dental Veneers; D006861:Hydrogen Peroxide; D016877:Oxidants; D013662:Tea; D014073:Tooth Bleaching; D014075:Tooth Discoloration
chemical_list: C483502:Clearfil ST; D003069:Coffee; D003188:Composite Resins; C466112:Esthet-X; C452225:Filtek A110 composite resin; D016877:Oxidants; D013662:Tea; D006861:Hydrogen Peroxide