title: Effect of Er:YAG laser on tensile bond strength of sealants in primary teeth.
abstract: OBJECTIVE
  The purpose of this in vitro study was to evaluate the tensile bond strength of sealants in primary molars after the surface pretreatment with an Er:YAG laser.
  
  
  METHODS
  Thirty primary molars were selected, and their roots were removed. Crowns were embedded in polyester resin and enamel surfaces were flattened. The bonding site was delimited, and samples were randomly assigned to 3 groups according to the surface pretreatment: (1) group 1=37% phosphoric acid; (2) group 2=Er:YAG laser; and (3) group 3=Er:YAG laser+37% phosphoric acid. Specimens were adapted to a metallic device, a split matrix was positioned on the surface of each sample and the FluroShield sealant was inserted into the matrix with a Centrix injector". Samples were stored for 48 hours, thermocycled, and subjected to a bond strength test (50 Kgf at 0.5 mm/minute).
  
  
  RESULTS
  Means in MPa (+/-SD) were: (1) group 1=10.80+/-3.28; (2) group 2=4.17+/-2.31; and (3) group 3=12.85+/-2.14. Analysis of variance and Tukey test revealed a statistical similarity between groups 1 (37% phosphoric acid) and 3 (Er:YAG laser+37% phosphoric acid). Treatment with the Er:YAG laser solely produced the lowest average and was statistically different from the other groups.
  
  
  CONCLUSIONS
  Conditioning with the Er:YAG laser may influence the sealant's bond strength; nevertheless, the subsequent application of acid is mandatory.
authors.affiliation: Department of Pediatric Clinic, Preventive and Social Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo (USP), São Paulo, Brazil.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Borsatto
authors.forename: Silmara Aparecida Milori
authors.initials: SA
authors.lastname: Corona
authors.forename: Fernando Pagnano
authors.initials: FP
authors.lastname: de Araújo
authors.forename: Aline Evangelista
authors.initials: AE
authors.lastname: de Souza-Gabriel
authors.forename: Jesus Djalma
authors.initials: JD
authors.lastname: Pécora
authors.forename: Regina Guenka
authors.initials: RG
authors.lastname: Palma-Dibb
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate; D001840:Dental Bonding; D003743:Dental Enamel; D045662:Dental Etching / Q000379:methods*; D003799:Dental Stress Analysis; D006801:Humans; D053844:Lasers, Solid-State; D008422:Materials Testing; D008963:Molar; D010756:Phosphoric Acids; D010895:Pit and Fissure Sealants; D011140:Polyurethanes; D013718:Tensile Strength; D014094:Tooth, Deciduous
chemical_list: D010756:Phosphoric Acids; D010895:Pit and Fissure Sealants; D011140:Polyurethanes; C086661:Fluoroshield; D017438:Bisphenol A-Glycidyl Methacrylate; C030242:phosphoric acid