title: Color stability of a nanofill composite: effect of different immersion media.
abstract: OBJECTIVE
  The aim of this in vitro study was to evaluate the color stability of a nanofill composite resin (Filtek Z350) in different immersion media.
  
  
  METHODS
  Twelve resin-based composite specimens were prepared using a silicon cylindrical mold measuring congruent with 1mm of thickness and congruent with 10mm of diameter. Specimens were light-cured for 40 s from both sides using a LED Radii at 1400 mW/cm(2) and were randomized into 4 groups (n= 3) according to immersion media: coffee, yerba mate, grape juice or water (control solution). A digital spectrophotometer was used to evaluate the color changes at baseline and at 1-week after immersion in each solution. Specimens were stored in the different staining media for 4 h/day during 1 week. The color differences (DE) were analyzed by paired t-test and one-way ANOVA with complementary Tukey test (p<0.05).
  
  
  RESULTS
  After 1-week of immersion, a perceptive color change for the group stored in the grape juice compared to baseline (p=0.008) was observed. Coffee and yerba mate did not show any color changes visible for the human eyes or significantly different from the control group (p>0.05)
  
  
  CONCLUSIONS
  The findings of the present study suggest that the tested nanofill resin-based composite was susceptible to staining by substances present in the grape juice.
authors: Department of Operative Dentistry, Dental School, Federal University of Pelotas, Pelotas, RS, Brazil.
authors: Silvia Terra
authors: ST
authors: Fontes
authors: María Raquel
authors: MR
authors: Fernández
authors: Claudia Modena
authors: CM
authors: de Moura
authors: Sônia Saeger
authors: SS
authors: Meireles
mesh_terms: D001628:Beverages; D003069:Coffee / Q000737:chemistry; D003116:Color; D004396:Coloring Agents / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D055117:Curing Lights, Dental; D003764:Dental Materials / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D030019:Ilex paraguariensis / Q000737:chemistry; D007101:Immersion; D008422:Materials Testing; D053761:Nanocomposites / Q000737:chemistry*; D013053:Spectrophotometry; D013499:Surface Properties; D013997:Time Factors; D027843:Vitis / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D003069:Coffee; D004396:Coloring Agents; D003188:Composite Resins; D003764:Dental Materials; C533204:filtek Z350; D014867:Water