title: Microleakage of a resin sealant after acid-etching, Er:YAG laser irradiation and air-abrasion of pits and fissures.
abstract: OBJECTIVE
  The aim of this in vitro study was to assess microleakage underneath a filled pit-and-fissure sealant bonded to occlusal surfaces treated by four enamel etching techniques.
  
  
  BACKGROUND
  There has been no report of a study assessing microleakage of a pit-and-fissure sealant, comparing acid-etching, Er:YAG laser and air-abrasion for treating enamel surface.
  
  
  METHODS
  Forty extracted human third molars were selected and randomly assigned into four groups of ten teeth: group I, the occlusal surfaces were acid-etched; group II, a very short pulsed Er:YAG laser was used to treat the surfaces; group III, aluminum oxide air-abrasion was associated with acid-etching; group IV, Er:YAG laser was associated with acid-conditioning. The surfaces were sealed and the teeth were stored for 7 days in distilled water. Then, specimens were thermocycled, immersed in a 0.2% rhodamine solution, sectioned, and analyzed for leakage using an optical microscope connected to a video camera. The images were digitized and analyzed by software that allowed microleakage assessment in millimeters.
  
  
  RESULTS
  Statistical analysis showed that occlusal surfaces treated exclusively by the Er:YAG laser (group II) provided the poorest marginal sealing and that acid-etching (group I) was statistically similar to aluminum oxide air-abrasion + acid etching (group III) and to Er:YAG laser + acid-etching (group IV).
  
  
  CONCLUSIONS
  The results suggest that complementing either air-abrasion or Er:YAG laser irradiation with a subsequent acid-conditioning did not lessen microleakage at the enamel-sealant interface when compared with an acid-etched group. It was also observed that treating the enamel surface exclusively by Er:YAG laser resulted in the highest degree of leakage.
authors.affiliation: Ribeirão Preto School of Dentistry, University of São Paulo, SP, Brazil.
authors.forename: M C
authors.initials: MC
authors.lastname: Borsatto
authors.forename: S A
authors.initials: SA
authors.lastname: Corona
authors.forename: R G
authors.initials: RG
authors.lastname: Dibb
authors.forename: R P
authors.initials: RP
authors.lastname: Ramos
authors.forename: J D
authors.initials: JD
authors.lastname: Pécora
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods*; D020906:Air Abrasion, Dental; D003750:Dental Fissures / Q000628:therapy*; D003763:Dental Leakage / Q000517:prevention & control*; D006801:Humans; D053685:Laser Therapy; D008855:Microscopy, Electron, Scanning; D008964:Molar, Third; D010895:Pit and Fissure Sealants; D011897:Random Allocation; D019279:Resin Cements; D013499:Surface Properties
chemical_list: D010895:Pit and Fissure Sealants; D019279:Resin Cements