title: Effects of acidulated phosphate fluoride gel application on surface roughness, gloss and colour of different type resin composites.
abstract: OBJECTIVE
  Application of acidulated phosphate fluoride (APF) gel has been reported to cause deterioration of resin composites. This study investigated the effects of APF gel application on surface roughness, gloss and colour of resin composites.
  
  
  METHODS
  A2-shade resin disks of 2mm thickness polished with 180-grit and 3000-grit SiC papers were made with Estelite Σ Quick (EQ), Clearfil Majesty (CM) and Beautifil II (B2). Six disks were prepared for each group. APF gel was applied in a 3mm thickness on the top surface of resin disks and left for 30min followed by rinsing and ultrasonic washing. This procedure was repeated 4 times. The L*a*b* values, colour difference (ΔE*ab), opacity, surface gloss and roughness of specimens before and after APF application were compared. Data were analysed ANOVA and Fisher's PLSD test with α=0.05.
  
  
  RESULTS
  For the 3000-grit polishing groups, the order of influence of APF gel application on colour of resin composites was CM>B2>EQ. Both in the 180- and 3000-grit polishing groups, colour difference before and after APF gel application was hard to detect (CM and B2) or impossible to detect (EQ) by naked eye. On the other hand, for all the resin composites, the gloss was significantly decreased by APF gel application. APF gel appeared to cause deterioration and dissolution of resin composites used in this study.
  
  
  CONCLUSIONS
  In this limited study, supra-nano spherical filled Estelite Σ Quick showed the least change on colour, gloss and surface roughness by APF gel application.
authors.affiliation: Department of Pediatric Dentistry, Course of Medical and Dental Science, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1, Sakamoto, Nagasaki 852-8588, Japan. hosoya@nagasaki-u.ac.jp
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Hosoya
authors.forename: Takanobu
authors.initials: T
authors.lastname: Shiraishi
authors.forename: Regina M
authors.initials: RM
authors.lastname: Puppin-Rontani
authors.forename: John M
authors.initials: JM
authors.lastname: Powers
mesh_terms: D000149:Acidulated Phosphate Fluoride; D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate; D003116:Color; D003188:Composite Resins / Q000737:chemistry; D008422:Materials Testing; D053761:Nanocomposites; D013499:Surface Properties
chemical_list: C470433:Beautifil composite resin; D003188:Composite Resins; C507124:Estelite sigma; C541508:clearfil majesty; D000149:Acidulated Phosphate Fluoride; D017438:Bisphenol A-Glycidyl Methacrylate