title: Effect of fluoride varnish supplemented with sodium trimetaphosphate on enamel erosion and abrasion.
abstract: OBJECTIVE
  To assess in vitro the effect on enamel erosion (ERO) and erosion followed by abrasion (ERO+ABR) of varnishes with different fluoride concentrations, supplemented or not with sodium trimetaphosphate (TMP).
  
  
  METHODS
  Bovine enamel blocks were randomly divided into six groups according to the type of varnish used: placebo (no F), NaF 5%, NaF 2.5%, NaF 2.5% plus TMP 3.5%, NaF 2.5% plus TMP 5%, NaF 2.5% plus TMP 10%. Varnishes were tested for ERO and ERO+ABR, separately for 3 and 5 days. ERO was done by immersion in Sprite Zero (5 minutes, 4x/day), while ERO+ABR was performed by brushing for 15 seconds after each erosive challenge. Enamel wear (microm) and cross-sectional hardness (AKHN) were assessed after the experimental periods. Data were analyzed by ANOVA, Tukey's test and Pearson's correlation coefficient (P< 0.05).
  
  
  RESULTS
  Varnishes supplemented with TMP promoted significantly lower wear and hardness loss when compared to the other treatments in all conditions studied (P< 0.05). Similar wear rates were observed for the placebo, NaF 2.5% and NaF 5% varnishes (P> 0.05). Greater wear was observed after 5 days of ERO and ERO+ABR when compared with 3 days (P< 0.05). Positive and significant correlations were found between enamel wear and AKHN. No dose-response relationship was found between TMP concentration and wear and hardness. It was concluded that fluoride varnishes supplemented with TMP had a higher protective effect against ERO and ERO+ABR, which was associated with a reduction in enamel softening.
authors.forename: Michele Maurício
authors.initials: MM
authors.lastname: Manarelli
authors.forename: Marcelo Juliano
authors.initials: MJ
authors.lastname: Moretto
authors.forename: Kikue Takebayashi
authors.initials: KT
authors.lastname: Sassaki
authors.forename: Cleide Cristina Rodrigues
authors.initials: CC
authors.lastname: Martinhon
authors.forename: Juliano Pelim
authors.initials: JP
authors.lastname: Pessan
authors.forename: Alberto Carlos Botazzo
authors.initials: AC
authors.lastname: Delbem
mesh_terms: D000818:Animals; D002253:Carbonated Beverages / Q000009:adverse effects; D002327:Cariostatic Agents / Q000737:chemistry / Q000627:therapeutic use*; D002417:Cattle; D003743:Dental Enamel / Q000187:drug effects* / Q000473:pathology; D004058:Diffusion; D005460:Fluorides, Topical / Q000737:chemistry / Q000627:therapeutic use*; D006244:Hardness; D006863:Hydrogen-Ion Concentration; D010919:Placebos; D011122:Polyphosphates / Q000737:chemistry / Q000627:therapeutic use*; D011897:Random Allocation; D012464:Saliva, Artificial / Q000737:chemistry; D013997:Time Factors; D014072:Tooth Abrasion / Q000473:pathology / Q000517:prevention & control*; D014077:Tooth Erosion / Q000473:pathology / Q000517:prevention & control*; D014099:Toothbrushing / Q000379:methods
chemical_list: D002327:Cariostatic Agents; D005460:Fluorides, Topical; D010919:Placebos; D011122:Polyphosphates; D012464:Saliva, Artificial; C009293:trimetaphosphoric acid