title: Effect of two fluoride varnishes on the color stability of three resin-based restorative materials: an in vitro study.
abstract: OBJECTIVE
  The aim of the present study was to evaluate the effect of two fluoride varnishes on color stability of three resin-based restorative materials.
  
  
  METHODS
  Fifty-four discs (14.5 × 1.7 mm) were fabricated from A2 and A3 shades of a compomer (F2000), a flowable composite (Z350), and a hybrid composite (Z250), and incubated at 37°C for 48 h. Dura Shield (colored) and Fluor Protector (colorless) fluoride varnishes were applied onto the discs. The coating was cleaned using a low-speed handpiece and nylon bristle brush after 24 h of storage in distilled water. A second coating was then applied. A control group with no coating was immersed in distilled water and used. The CIE L*a*b* color scale was measured before the treatments and following each cleaning utilizing a spectrophotometer.
  
  
  RESULTS
  The colored fluoride varnish exhibited the highest overall color change (∆E) after the first and the second cleaning procedures in all the materials. Among these, the greatest color change was observed in the A3 shade of F2000, followed by the A3 shade of Z-250. The ∆E was less than 3.3 in all groups, and was therefore clinically acceptable.
  
  
  CONCLUSIONS
  Color changes following the application of fluoride varnishes were found to be clinically acceptable in all groups.
authors.affiliation: Department of Pediatric Dentistry, Dental School, Islamic Azad University of Dentistry, Tehran, Iran. raha.tafaroji@yahoo.com.
authors.forename: Raha
authors.initials: R
authors.lastname: Tafaroji
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mina
authors.initials: M
authors.lastname: Biria
authors.affiliation: Color physics Department, Institute for Color Science and Technology, Tehran, Iran.
authors.forename: Farhad
authors.initials: F
authors.lastname: Ameri
authors.affiliation: Restorative Dentistry Department, Dental Research Center, Shahid Beheshti Dental School, Tehran, Iran.
authors.forename: Hassan
authors.initials: H
authors.lastname: Torabzadeh
authors.affiliation: Department of Periodontology, Dental school, Babol University of Medical Sciences, Babol, Iran.
authors.forename: Pasha
authors.initials: P
authors.lastname: Qahari
authors.affiliation: Department of Basic Sciences, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Akbarzadeh Baghban
mesh_terms: D001672:Biocompatible Materials; D003116:Color; D003124:Colorimetry / Q000706:statistics & numerical data; D003188:Composite Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003793:Dental Restoration, Permanent; D004338:Drug Combinations; D005460:Fluorides, Topical / Q000737:chemistry*; D008422:Materials Testing; D011140:Polyurethanes / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D012969:Sodium Fluoride; D014867:Water / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D003188:Composite Resins; D003764:Dental Materials; D004338:Drug Combinations; C444701:Filtek Z250; D005460:Fluorides, Topical; D011140:Polyurethanes; D012821:Silanes; C533204:filtek Z350; C111840:flowable hybrid composite; C023807:sodium fluoride topical preparation; D014867:Water; C022599:Fluor Protector; D012969:Sodium Fluoride
keywords: 
  in vitro
  ; biocompatible materials; color; fluoride varnish; resin-based dental restorative material