title: Effect of the addition of nano-sized sodium hexametaphosphate to fluoride toothpastes on tooth demineralization: an in vitro study.
abstract: OBJECTIVE
  This study evaluated the effect of toothpastes containing 1100 ppm F associated with nano-sized sodium hexametaphosphate (HMPnano) on enamel demineralization in vitro using a pH-cycling model.
  
  
  METHODS
  Bovine enamel blocks (4 mm × 4 mm, n = 72) selected by initial surface hardness (SHi) were randomly allocated into six groups (n = 12), according to the test toothpastes: without fluoride or HMPnano (Placebo), 550 ppm F (550F), 1100 ppm F (1100F), 1100F plus HMPnano at concentrations of 0.25% (1100F/0.25%HMPnano), 0.5% (1100F/0.5%HMPnano), and 1.0% (1100F/1.0%HMPnano). Blocks were treated 2×/day with slurries of toothpastes and submitted to five pH cycles (demineralizing/remineralizing solutions) at 37 °C. Next, final surface hardness (SHf), integrated loss subsurface hardness (ΔKHN), integrated mineral loss (gHAp × cm-3), and enamel fluoride (F) concentrations were determined. Data were analyzed by ANOVA and Student-Newman-Keuls test (p < 0.001).
  
  
  RESULTS
  Toothpaste with 1100F/0.5%HMPnano led to the lowest mineral loss and the highest mineral concentration among all groups, which were 26% (SHf) and 21% (ΔKHN) lower and ~58% higher (gHAp × cm-3) when compared to 1100F (p < 0.001). Similar values of enamel F were observed for all fluoridated toothpastes (p > 0.001).
  
  
  CONCLUSIONS
  The addition of 0.5%HMPnano to a 1100 F toothpaste significantly enhances its effects against enamel demineralization when compared to its counterpart without HMPnano in vitro.
  
  
  CONCLUSIONS
  Toothpaste containing 1100 ppm F associated with HMPnano has a higher potential to reduce the demineralization compared to 1100 ppm F. This toothpaste could be a viable alternative to patients at high risk of caries.
authors.affiliation: Department of Pediatric Dentistry and Public Health, São Paulo State University (Unesp), School of Dentistry, Araçatuba, Rua José Bonifácio 1193, Araçatuba, 16015-050, São Paulo, Brazil.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Dalpasquale
authors.affiliation: Department of Pediatric Dentistry and Public Health, São Paulo State University (Unesp), School of Dentistry, Araçatuba, Rua José Bonifácio 1193, Araçatuba, 16015-050, São Paulo, Brazil.
authors.forename: Alberto Carlos Botazzo
authors.initials: ACB
authors.lastname: Delbem
authors.affiliation: Department of Pediatric Dentistry and Public Health, São Paulo State University (Unesp), School of Dentistry, Araçatuba, Rua José Bonifácio 1193, Araçatuba, 16015-050, São Paulo, Brazil.
authors.forename: Juliano Pelim
authors.initials: JP
authors.lastname: Pessan
authors.affiliation: Department of Pediatric Dentistry and Public Health, São Paulo State University (Unesp), School of Dentistry, Araçatuba, Rua José Bonifácio 1193, Araçatuba, 16015-050, São Paulo, Brazil.
authors.forename: Gabriel Pereira
authors.initials: GP
authors.lastname: Nunes
authors.affiliation: LIEC-Department of Chemistry, Federal University of São Carlos (UFSCar), Rodovia Washington Luís, São Carlos, 13565-905, São Paulo, Brazil.
authors.forename: Luiz Fernando
authors.initials: LF
authors.lastname: Gorup
authors.affiliation: LIEC-Department of Chemistry, Federal University of São Carlos (UFSCar), Rodovia Washington Luís, São Carlos, 13565-905, São Paulo, Brazil.
authors.forename: Francisco Nunes Souza
authors.initials: FNS
authors.lastname: Neto
authors.affiliation: LIEC-Department of Chemistry, Federal University of São Carlos (UFSCar), Rodovia Washington Luís, São Carlos, 13565-905, São Paulo, Brazil.
authors.forename: Emerson Rodrigues
authors.initials: ER
authors.lastname: de Camargo
authors.affiliation: Department of Pediatric Dentistry and Public Health, São Paulo State University (Unesp), School of Dentistry, Araçatuba, Rua José Bonifácio 1193, Araçatuba, 16015-050, São Paulo, Brazil. marcelledanelon@hotmail.com.
authors.forename: Marcelle
authors.initials: M
authors.lastname: Danelon
mesh_terms: D000818:Animals; D002417:Cattle; D003743:Dental Enamel / Q000187:drug effects*; D005459:Fluorides / Q000494:pharmacology*; D006244:Hardness; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D049329:Nanostructures; D010710:Phosphates / Q000494:pharmacology*; D011897:Random Allocation; D013499:Surface Properties; D017001:Tooth Demineralization / Q000139:chemically induced*; D014100:Toothpastes / Q000494:pharmacology*
chemical_list: D010710:Phosphates; D014100:Toothpastes; C012980:fluorophosphate; C009285:sodium polymetaphosphate; D005459:Fluorides
keywords: Demineralization; Dental enamel; Nano-size; Polyphosphates; Toothpastes