title: Effect of toothpastes containing different NaF concentrations or a SnF2/NaF combination on root dentine erosive lesions,in vitro.
abstract: BACKGROUND
  Fluoride toothpastes presumably offer some protection against acid erosion. However, uncertainty exists towards fluoride's efficacy relatively to the concentration and the type of chemical compound used. Thisin vitrostudy evaluated the relative efficacy of toothpastes containing sodium fluoride in different concentrations or a stabilized stannous fluoride/sodium fluoride system on root dentine erosion.
  
  
  METHODS
  Bovine dentin specimens were allocated into four groups (n=10): control (no F), 1450ppm F (as NaF), 5000ppm F (as NaF) and 1450ppm F (1100ppm as stabilized SnF2 and 350ppm as NaF)/sodium hexamethaphosphate. The specimens were submitted to 6 daily cycles of erosion (0.3% v/v citric acid, pH=3.2, 20 min) and remineralization (~22h), interspersed by 2-min immersions in 1:3 w/v of dentifrice/distilled water slurries. Subsequently, they were subjected to a 24-h acid resistance test (0.3% v/v citric acid, pH=3.2) without any further treatments. Surface loss was quantified by contact profilometry. Data were analysed through one-way ANOVA and Bonferroni's tests (p≤0.05).
  
  
  RESULTS
  In both experiments, all fluoride groups, showed significantly less tissue loss compared to the control (p<0.001-p=0.018). During erosion cycling, no significant differences were found among the fluoride groups. During the acid resistance test, the 5000ppm F toothpaste produced significantly superior effect than both 1450ppm F products (p=0.010, (p<0.001), which performed similarly.
  
  
  CONCLUSIONS
  Under less aggressive erosive conditions, fluoride toothpastes did not differ in their ability to protect dentine surfaces. However, in severely erosive environment, the 5000ppm F toothpaste performed superiorly to the other tested products.Key words:Dentine, sodium fluoride, stannous fluoride, tooth erosion, toothpaste, contact profilometry.
authors.affiliation: Visiting Postdoctoral Researcher, Department of Preventive and Community Dentistry, Dental School, National & Kapodistrian University of Athens, Athens, Greece.
authors.forename: Iliana
authors.initials: I
authors.lastname: Diamanti
authors.affiliation: Associate Professor, Department of Preventive and Community Dentistry, Dental School, National & Kapodistrian University of Athens, Athens, Greece.
authors.forename: Haroula
authors.initials: H
authors.lastname: Koletsi-Kounari
authors.affiliation: Associate Professor, Department of Preventive and Community Dentistry, Dental School, National & Kapodistrian University of Athens, Athens, Greece.
authors.forename: Eleni
authors.initials: E
authors.lastname: Mamai-Homata