title: Microleakage of class V glass ionomer restorations after conventional and Er:YAG laser preparation.
abstract: OBJECTIVE
  The aim of this study was to investigate the microleakage in class V cavities following Er:YAG laser or conventional preparation restored with two conventional glass ionomer cements (cGIC) and to evaluate the effect of conditioning on laser-prepared surfaces.
  
  
  BACKGROUND
  Information on this topic related to cGIC is scarce.
  
  
  METHODS
  Sixty class V cavities were assigned to six groups: I and IV were Er:YAG-lased, II and V Er:YAG-lased and conditioned, and III and VI conventionally prepared and conditioned. Groups I, II, and III, were restored with Ketac Fil Plus Applicap; groups IV, V, and VI were restored with Fuji IX GP Capsule. Then, teeth were stored in distilled water (37 degrees C, 24 h), thermal cycled 1500 times (5-55 degrees C), placed in a 2% aqueous solution of methylene blue (37 degrees C, 24 h), embedded in acrylic resin, sectioned oro-facially, and analyzed for leakage.
  
  
  RESULTS
  Statistically significant differences between occlusal and cervical regions were observed (p < 0.05). Group III showed significantly more microleakage at the occlusal margin compared to group II (p = 0.022). Group V showed significantly more microleakage at the gingival margin than group VI (p = 0.022). Leakage on the occlusal margins was significantly higher in group III than in group VI (p = 0.038). Scanning electron microscopy indicated that conditioning of laser-prepared dentin with Ketac conditioner partially closed the tubules' orifices, whereas the use of GC conditioner completely obliterated the tubules.
  
  
  CONCLUSIONS
  The application of Ketac Fil Plus to laser-prepared enamel and dentin resulted in a better and more reproducible seal compared to conventionally prepared tooth surfaces. When using the more viscous Fuji IX application, Er:YAG lasing did not improve marginal adaptation.
authors.affiliation: Department of Operative Dentistry and Endodontology, Dental School, Ghent University, Ghent University Clinic, Gent, Belgium.
authors.forename: Katleen Ilse Maria
authors.initials: KI
authors.lastname: Delme
authors.forename: Peter Jean
authors.initials: PJ
authors.lastname: Deman
authors.forename: Samir
authors.initials: S
authors.lastname: Nammour
authors.forename: Roeland Jozef Gentil
authors.initials: RJ
authors.lastname: De Moor
mesh_terms: D003737:Dental Cavity Preparation / Q000379:methods*; D003763:Dental Leakage; D005899:Glass Ionomer Cements; D006801:Humans; D007834:Lasers; D012387:Root Canal Filling Materials
chemical_list: D005899:Glass Ionomer Cements; D012387:Root Canal Filling Materials