title: Combined effect of fluoride varnish to Er:YAG or Nd:YAG laser on permeability of eroded root dentine.
abstract: OBJECTIVE
  This study evaluated the combined effect of fluoride varnish to Er:YAG or Nd:YAG laser on permeability of eroded root dentine.
  
  
  METHODS
  Sixty slabs of bovine root dentine (2×2×2mm) were eroded with citric acid 0.3% (pH 3.2) during 2h and then kept in artificial saliva during 24h. Specimens were randomly assigned in 6 groups (n=10), to receive the following treatments: fluoride varnish; fluoride varnish+Er:YAG laser; fluoride varnish+Nd:YAG laser; non-fluoride varnish; non-fluoride varnish+Er:YAG laser; non-fluoride varnish+Nd:YAG laser. The Er:YAG (100mJ, 3Hz) and Nd:YAG (70mJ, 15Hz) were applied for 10s. Specimens were subjected to further erosive challenges with citric acid 0.3% 4×/day, during 1min, for 5 days, remaining in artificial saliva between cycles. Dentin permeability was then assessed. Two-way ANOVA demonstrated no significant interaction between laser and varnish (p=0.858).
  
  
  RESULTS
  No effect was also detected for the main factor varnish (p=0.768), while permeability of eroded root dentin was significantly lower when such substrate was laser-irradiated, no matter the laser source (p<0.001).
  
  
  CONCLUSIONS
  This study concluded that Er:YAG and Nd:YAG lasers can be employed to control the permeability of eroded root dentin, regardless of fluoride varnish application.
authors.affiliation: University of São Paulo, School of Dentistry of Ribeirão Preto-USP, Department of Restorative Dentistry, Ribeirão Preto, Av. do café, s/n, Monte Alegre, CEP:14040-904 São Paulo, Brazil.
authors.forename: Sandra
authors.initials: S
authors.lastname: Chiga
authors.affiliation: University of São Paulo, School of Dentistry of Ribeirão Preto-USP, Department of Restorative Dentistry, Ribeirão Preto, Av. do café, s/n, Monte Alegre, CEP:14040-904 São Paulo, Brazil.
authors.forename: Carmen Victoria Torres
authors.initials: CV
authors.lastname: Toro
authors.affiliation: University of São Paulo, School of Dentistry of Ribeirão Preto-USP, Department of Restorative Dentistry, Ribeirão Preto, Av. do café, s/n, Monte Alegre, CEP:14040-904 São Paulo, Brazil.
authors.forename: Taísa Penazzo
authors.initials: TP
authors.lastname: Lepri
authors.affiliation: São Leopoldo Mandic Institute and Dental Research Center, Department of Restorative Dentistry, Campinas, Rua Dr. José Rocha Junqueira, 13, Swift, CEP:13045-755 São Paulo, Brazil.
authors.forename: Cecília Petroso
authors.initials: CP
authors.lastname: Turssi
authors.affiliation: University of São Paulo, School of Dentistry of Ribeirão Preto-USP, Department of Restorative Dentistry, Ribeirão Preto, Av. do café, s/n, Monte Alegre, CEP:14040-904 São Paulo, Brazil.
authors.forename: Vivian
authors.initials: V
authors.lastname: Colucci
authors.affiliation: University of São Paulo, School of Dentistry of Ribeirão Preto-USP, Department of Restorative Dentistry, Ribeirão Preto, Av. do café, s/n, Monte Alegre, CEP:14040-904 São Paulo, Brazil. Electronic address: silmaracorona@forp.usp.br.
authors.forename: Silmara Aparecida Milori
authors.initials: SA
authors.lastname: Corona
mesh_terms: D000818:Animals; D002417:Cattle; D019343:Citric Acid; D003804:Dentin / Q000187:drug effects / Q000528:radiation effects; D003806:Dentin Permeability / Q000187:drug effects* / Q000528:radiation effects*; D005460:Fluorides, Topical / Q000008:administration & dosage / Q000528:radiation effects*; D006863:Hydrogen-Ion Concentration; D053844:Lasers, Solid-State; D011897:Random Allocation; D012464:Saliva, Artificial; D014077:Tooth Erosion / Q000188:drug therapy / Q000209:etiology / Q000517:prevention & control; D014092:Tooth Root / Q000187:drug effects* / Q000528:radiation effects*
chemical_list: D005460:Fluorides, Topical; D012464:Saliva, Artificial; D019343:Citric Acid
keywords: Dental erosion; Dentin; Fluoride; Lasers