title: Effect of Acid Etching on Long-term Microleakage of Nano Ionomer Restorations in Burand Laser-prepared Cavities in Primary Teeth.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effect of etching on marginal sealing of nanofilled resin-modified glass ionomer restorations in Class V cavities in primary teeth prepared with an Er, Cr:YSGG laser compared to bur preparation.
  
  
  METHODS
  Standard Class V cavities were prepared on the buccal surfaces of 56 extracted primary canines that were randomly divided into four groups of 14 teeth each, according to laser or bur preparation and whether acid etching was used or not in the cavity. All cavities were restored with Nano primer/Ketac N100. After storage for six months in water and 2,000 thermal cycles, the specimens were placed in a one percent basic fuchsin dye solution. Dye penetration was evaluated with a stereomicroscope. The data were analyzed via nonparametric tests (P<.05).
  
  
  RESULTS
  Etching in bur- and laser-prepared cavities significantly reduced enamel microleakage (P=.031 and P=.001, respectively). At the dentin margin, etching significantly increased microleakage in bur-prepared cavities (P=.009) and significantly decreased it in laser-prepared cavities (P=.009).
  
  
  CONCLUSIONS
  Etching may improve the sealing ability of Ketac N100 at both margins in laser-prepared cavities and at the enamel margin in bur-prepared cavities. It had an adverse effect on dentinal sealing in aged Ketac N100 restorations in primary teeth.
authors.affiliation: Department of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Fereshteh
authors.initials: F
authors.lastname: Shafiei
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran. memarpour@sums.ac.ir.
authors.forename: Mahtab
authors.initials: M
authors.lastname: Memarpour
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods*; D003731:Dental Caries / Q000628:therapy*; D003737:Dental Cavity Preparation / Q000379:methods*; D003763:Dental Leakage / Q000517:prevention & control*; D003793:Dental Restoration, Permanent / Q000379:methods*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D053844:Lasers, Solid-State / Q000627:therapeutic use; D049329:Nanostructures; D012394:Rosaniline Dyes; D014094:Tooth, Deciduous / Q000648:ultrastructure*
chemical_list: D005899:Glass Ionomer Cements; D012394:Rosaniline Dyes