title: Er:YAG laser cavity preparation and composite resin bonding with a single-component adhesive system: relationship between shear bond strength and microleakage.
abstract: OBJECTIVE
  The purpose of this study was to assess the performances of a single-component adhesive system when an Er:YAG laser was used to prepare cavities.
  
  
  METHODS
  Shear bond strength tests were performed on composite rods bonded with a single-component adhesive system to dentin surfaces prepared using either bur+acid, Er:YAG laser (fluence = 44 J/cm2), or Er:YAG laser+acid. Class V cavities were prepared differently according to the molar surface: buccal surfaces were prepared using a diamond bur, and lingual surfaces using the Er:YAG laser. In group 1, cavity walls were not acid treated after Er:YAG laser preparation. In group 2, only the enamel walls were acid treated. In group 3, all the enamel and dentin walls were acid treated. Microleakage was assessed using a methylene blue dye penetration method.
  
  
  RESULTS
  Bond strength values did not differ significantly between the three groups (P = 0.162). Better marginal adaptation was obtained between the composite resin and cavity walls when Er:YAG laser preparation was followed by a total acid etching (P = 0.008).
  
  
  CONCLUSIONS
  Our results supported the use of single-component adhesive systems in cavities prepared using Er:YAG laser. The step of acid etching must be maintained for the whole cavity walls in regard of the microleakage values.
authors: Laboratory of Surfaces and Interfaces in Odontology, University of Nice-Sophia Antipolis, Nice, France. Marie-France.BERTRAND@unice.fr
authors: Marie-France
authors: MF
authors: Bertrand
authors: Gianfranco
authors: G
authors: Semez
authors: Eric
authors: E
authors: Leforestier
authors: Michèle
authors: M
authors: Muller-Bolla
authors: Samir
authors: S
authors: Nammour
authors: Jean-Paul
authors: JP
authors: Rocca