title: An in vitro study of the effect of aluminum and the combined effect of strontium, aluminum, and fluoride elements on early enamel carious lesions.
abstract: The purpose of this in vitro study was to evaluate the effect of aluminum and of combined strontium, aluminum, and fluoride treatments on enamel demineralization and remineralization. During a 6-day pH-cycling protocol, pre-softened bovine enamel slabs were immersed twice daily for 1 min in the following experimental solutions: (a) distilled water [W] (negative control); (b) 1,000 ppm F [F] (positive control); (c) 1,000 ppm Al [Al]; (d) 1,000 ppm Al,1,000 ppm F applied interchangeably [Al-F]; (e) 1,000 ppm Al, 1,000 ppm F, applied in sequential order [Al+F]; (f) combined 1,000 ppm Al and 150 ppm Sr [Al+Sr]; and (g) combined 150 ppm Sr and 1,000 ppm F [Sr+F]. Subsequently, the specimens were subjected to a 5-day acid resistance test. Lesions were evaluated quantitatively by performing surface microhardness and qualitatively by using polarized light microscopy. According to the results, solutions [Sr+F] and [Al-F] enhanced remineralization and inhibited demineralization as effectively as the [F] solution and significantly superiorly compared to [Al+Sr] and [Al] solutions. All tested solution groups, except for the [Al+Sr] group, presented significantly increased resistance to acidic attack, compared to [W]. PLM examination revealed that all solution groups, except for the [W] group, developed an acid-resistant zone at lesion surfaces. In conclusion, under the present experimental conditions, the combined strontium-fluoride and aluminum-fluoride treatments presented similar anti-caries efficacy compared to fluoride treatment alone, but they did not show evidence of synergistic activity on pre-softened enamel.
authors.affiliation: Dental School, National and Kapodistrian University of Athens, Athens, Greece.
authors.forename: Haroula
authors.initials: H
authors.lastname: Koletsi-Kounari
authors.forename: Eleni
authors.initials: E
authors.lastname: Mamai-Homata
authors.forename: Iliana
authors.initials: I
authors.lastname: Diamanti
mesh_terms: D000535:Aluminum / Q000494:pharmacology*; D000077410:Aluminum Chloride; D017607:Aluminum Compounds / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D002712:Chlorides / Q000494:pharmacology; D003731:Dental Caries / Q000517:prevention & control*; D003743:Dental Enamel / Q000737:chemistry / Q000187:drug effects* / Q000473:pathology; D004357:Drug Synergism; D005459:Fluorides / Q000494:pharmacology*; D006244:Hardness / Q000187:drug effects; D066298:In Vitro Techniques; D008859:Microscopy, Polarization; D012969:Sodium Fluoride / Q000494:pharmacology; D013324:Strontium / Q000494:pharmacology*; D017001:Tooth Demineralization / Q000517:prevention & control; D014089:Tooth Remineralization / Q000379:methods
chemical_list: D017607:Aluminum Compounds; D002712:Chlorides; D000077410:Aluminum Chloride; D012969:Sodium Fluoride; D000535:Aluminum; C025700:strontium chloride; D005459:Fluorides; D013324:Strontium; C032311:aluminum fluoride