title: Resin infiltrant for non-cavitated caries lesions: evaluation of color stability.
abstract: BACKGROUND
  The objective of thisin vitrostudy was to evaluate the over time color stability of one resin infiltrant (Icon) upon exposure to staining solutions (coffee and wine) compared with one nano-hybrid sealant (Grandio Seal), one transparent fissure sealant with fluoride (Control Seal) and one nanofilled composite (Filtek Supreme XTE).
  
  
  METHODS
  All materials were polymerized according to manufacturers' instructions into silicon rings (height 1 mm; internal diameter 6 mm; external diameter 8 mm) to obtain specimens identical in size. The specimens were immersed in staining solutions at room temperature over a 28-day test period. The control samples have not been subjected to the staining process. A colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, 28 days of the staining process. Shapiro Wilk test and Kruskal Wallis ANOVA were applied to assess significant differences among different materials. Means were compared with Scheffe's multiple-comparison test at the 0.05 level of significance.
  
  
  RESULTS
  In the case of all materials, immersion in solutions resulted in clinically perceivable color changes after 1 week (∆E < 3.3). Lowest CIE L* variation was registered for Control Seal and Grandio Seal both after 1 week and after 1 month, while Icon showed significantly higher variation (P< 0.05). Color coordinate CIE a* varied significantly more for Icon samples (P> 0.05). Color coordinate CIE b* varied similarly for all materials tested (P> 0.05).
  
  
  CONCLUSIONS
  Immersion in coffee or red wine resulted in clinically perceivable color changes for all materials tested. Icon showed the highest color variations both after 1 week and 1 month. Icon can fix the initial esthetic problem associated with white spot lesions, but the resin may become more discolored than other materials over time.Key words:CIE Lab, color stability, resin infiltrant.
authors.affiliation: Department of Clinical-Surgical, Diagnostic and Pediatric Sciences - Section of Dentistry, University of Pavia, Pavia, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Ceci
authors.affiliation: Department of Clinical-Surgical, Diagnostic and Pediatric Sciences - Section of Dentistry, University of Pavia, Pavia, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Rattalino
authors.affiliation: Department of Clinical-Surgical, Diagnostic and Pediatric Sciences - Section of Dentistry, University of Pavia, Pavia, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Viola
authors.affiliation: Department of Brain and Behavioural Sciences - Section of Statistic, University of Pavia, Pavia, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Beltrami
authors.affiliation: Department of Clinical-Surgical, Diagnostic and Pediatric Sciences - Section of Dentistry, University of Pavia, Pavia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Chiesa
authors.affiliation: Department of Clinical-Surgical, Diagnostic and Pediatric Sciences - Section of Dentistry, University of Pavia, Pavia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Colombo
authors.affiliation: Department of Clinical-Surgical, Diagnostic and Pediatric Sciences - Section of Dentistry, University of Pavia, Pavia, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Poggio