title: Corrosive effects of fluoride on titanium: investigation by X-ray photoelectron spectroscopy, atomic force microscopy, and human epithelial cell culturing.
abstract: High fluoride (F(-)) concentrations and acidic pH impair the corrosion resistance of titanium (Ti). Effects of F(-)-containing caries-preventive prophylactic rinses, and gels on Ti were investigated by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Human epithelial cell attachment and proliferation were investigated by dimethylthiazol-diphenyl tetrazolium bromide (MTT) and protein content assays. Aqueous 1% NaF solution (3800 ppm F(-), pH 4.5) or high (12,500 ppm) F(-) content gel (pH 4.8) strongly corroded the surface and modified its composition. XPS revealed formation of a strongly bound F(-)-containing complex (Na(2)TiF(6)). AFM indicated an increase in roughness (R(a)) of the surfaces: 10-fold for the NaF solution and smaller for the gel or a mouthwash (250 ppm F(-), pH 4.4). MTT revealed that cell attachment was significantly increased by the gel, but was not disturbed by either the mouthwash or the NaF. Cell proliferation determined by MTT decreased significantly only for the NaF-treated samples; protein content assay experiments showed no such effect. This study indicates that epithelial cell culturing results can depend on the method used, and the adverse effects of a high F(-) concentration and low pH should be considered when prophylactic gels are applied by patients with Ti implants or other dental devices.
authors.affiliation: Department of Prosthetic Dentistry, Faculty of Dentistry, University of Szeged, Tisza Lajos krt.64, 6720 Szeged, Hungary.
authors.forename: Anette
authors.initials: A
authors.lastname: Stájer
authors.forename: Krisztina
authors.initials: K
authors.lastname: Ungvári
authors.forename: István K
authors.initials: IK
authors.lastname: Pelsoczi
authors.forename: Hilda
authors.initials: H
authors.lastname: Polyánka
authors.forename: Albert
authors.initials: A
authors.lastname: Oszkó
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Mihalik
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Rakonczay
authors.forename: Márta
authors.initials: M
authors.lastname: Radnai
authors.forename: Lajos
authors.initials: L
authors.lastname: Kemény
authors.forename: András
authors.initials: A
authors.lastname: Fazekas
authors.forename: Kinga
authors.initials: K
authors.lastname: Turzó
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D002327:Cariostatic Agents / Q000737:chemistry; D002448:Cell Adhesion; D018929:Cell Culture Techniques; D049109:Cell Proliferation; D002478:Cells, Cultured; D003722:Dental Alloys / Q000737:chemistry; D015921:Dental Implants; D004847:Epithelial Cells / Q000502:physiology* / Q000648:ultrastructure; D005459:Fluorides / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D018625:Microscopy, Atomic Force; D009067:Mouthwashes / Q000737:chemistry; D013057:Spectrum Analysis / Q000379:methods; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D002327:Cariostatic Agents; D003722:Dental Alloys; D015921:Dental Implants; D009067:Mouthwashes; D014025:Titanium; D005459:Fluorides