title: Assessing microleakage of composite restorations in class V cavities prepared by Er:YAG laser irradiation or diamond bur.
abstract: BACKGROUND
  The aim of this study was to make a comparison between microleakage of conventionally restored class V cavities using bur and acid etchant and, the ones prepared and conditioned by Er:YAG laser.
  
  
  METHODS
  30 recently extracted intact caries and filling free human permanent molars were used for this study. Then, Cold cure acrylic resin was used to seal the apices. The samples were randomly assigned to 5 groups of six each. Class V cavities were prepared one on buccal and one on lingual surface of each sample. Group 1: cavity preparation by diamond bur and turbine + acid etch, Group 2: cavity preparation by Er:YAG laser + acid etch, Group 3: cavity preparation by Er:YAG laser + Laser etching, Group 4: cavity preparation by diamond bur and turbine + laser etching, Group 5: cavity preparation by Er:YAG laser with no conditioning procedure. The cavities restored with restorative composite resin. Samples were then immersed in 2% methylene blue solution for 24 hours. The data were then analyzed using Wilcoxon signed ranks test and Kruskal-Wallis statistical tests.
  
  
  RESULTS
  The Kruskal Wallis test showed a significant difference (P < 0.05) between enamel and cementum margin microleakage, while the higher microleakage was related to the cementum margin of restorations.
  
  
  CONCLUSIONS
  There was no significant difference in evaluating microleakeage degree of cavities prepared by Er:YAG laser and diamond bur.
authors.affiliation: Department of Restorative, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Sakineh
authors.initials: S
authors.lastname: Arami
authors.affiliation: Department of Dental Materials School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Sima
authors.initials: S
authors.lastname: Shahabi
authors.affiliation: Department of Restorative, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Masomeh
authors.initials: M
authors.lastname: Tabatabaie
authors.affiliation: PhD Candidate of Laser Dentistry, Laser Research Center of Dentistry, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Nasim
authors.initials: N
authors.lastname: Chiniforush
authors.affiliation: Department of Restorative Dentistry, Tehran, Iran.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Morshedi
authors.affiliation: Department of Restorative Dentistry, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Torabi
keywords: Cavity; Er:YAG laser; microleakage