title: Mineral content of ionomer cements and preventive effect of these cements against white spot lesions around restorations.
abstract: This study evaluated the ion exchange at the material/enamel interface and the preventive effect of restorative materials submitted to cariogenic challenge against white spot. Restorations in enamel/dentin of bovine teeth were performed with composite resin (Filtek™ Z250 - control group) and glass-ionomers cements - GICs (Ionomaster R™ and Fuji IX™ - experimental groups). Samples were grouped and submitted to neutral saliva (n = 15) or pH-cycling regimen (n = 15). After eight days of pH cycling, material/enamel interfaces were analyzed by EDX in order to determine the differences (p < 0.05) in ionic exchange (Ca, P, F, Al, Sr, and Si) between restorative materials and teeth. In addition, enamel white spot lesion formation was evaluated macroscopically (p < 0.05). Sr content was higher in the enamel of the control group (p > 0.05) versus the experimental groups. Ca and P content were higher in enamel than in restorative materials. After pH cycling, the GIC enamel bulk showed a significantly higher Sr content compared with the composite resin (p < 0.05). Filtek™ Z250 was not able to prevent white spot formation around restorations in comparison with Ionomaster R™ (p < 0.001) and Fuji IX™ (p = 0.004). GICs reduced white spot formation and presented a preventive effect (p = 0.051). GICs presented a greater percentage of fluoride, aluminum, and strontium, and proved effective in white spot lesion prevention around restorations.
authors.affiliation: Department of Metallurgical and Materials Engineering, PEMM/COPPE, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Lilian Fernanda Santos
authors.initials: LF
authors.lastname: Paiva
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Tatiana Kelly da Silva
authors.initials: TK
authors.lastname: Fidalgo
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Lucianne Cople
authors.initials: LC
authors.lastname: Maia
mesh_terms: D000818:Animals; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry* / Q000627:therapeutic use; D003731:Dental Caries / Q000517:prevention & control*; D003743:Dental Enamel / Q000187:drug effects*; D003793:Dental Restoration, Permanent / Q000379:methods*; D005899:Glass Ionomer Cements / Q000737:chemistry* / Q000627:therapeutic use; D007474:Ion Exchange; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008903:Minerals / Q000737:chemistry* / Q000627:therapeutic use; D012016:Reference Values; D015203:Reproducibility of Results; D018709:Statistics, Nonparametric; D013499:Surface Properties
chemical_list: D003188:Composite Resins; C444701:Filtek Z250; D005899:Glass Ionomer Cements; D008903:Minerals; C110713:fuji IX