title: [Study on the microleakage between the composite resin and cavity  wall after Er,Cr:YSGG laser preparation].
abstract: OBJECTIVE
  To evaluate microleakage between the composite resin and cavity wall after Er,Cr:YSGG laser preparation.
  
  
  METHODS
  Class V cavities were prepared in 30 sound extracted human premolars. The teeth were randomly divided into 3 groups (n=10).Group 1 was treated with Er,Cr:YSGG+37% phosphoric acid, group 2 was treated with Er,Cr:YSGG+FL-BOND and group 3 was treated with Er,Cr:YSGG+17% EDTA.Then the specimens were subjected to thermocycling and staining. The marginal microleakage was assessed by dye penetration method and scanning electronic microscope(SEM). The data was analyzed with SPSS11.0 software package.
  
  
  RESULTS
  In occlusal margins,microleakage in group 2 was significantly lower than that in the other two laser groups(P<0.05).No significant difference was found between group 1 and 3 by dye penetration method.The space between the restorations and tooth structure revealed that there was significant difference between group 2 and 3(P<0.05).No significant difference was found between the other two laser groups by SEM. In gingival margins, microleakage test and the space between the restorations and tooth structure revealed that there was no significant difference among the three laser groups.There was significant difference in microleakage between the occlusal and gingival margins only in group 2(P<0.05).
  
  
  CONCLUSIONS
  It is concluded that self-etch adhesive system was effective in reducing microleakage of the occlusal margins between the composite resin and the cavity wall after Er,Cr:YSGG laser preparation.There was no significant difference in microleakage after using a total etch adhesive system and EDTA.
authors.affiliation: Department of VIP, School of Stomatology, China Medical University, Shenyang 110002, China. jia.xing.ya@tom.com
authors.forename: Xing-ya
authors.initials: XY
authors.lastname: Jia
authors.forename: Feng-yan
authors.initials: FY
authors.lastname: Wang
authors.forename: Ce
authors.initials: C
authors.lastname: Liu
mesh_terms: D001641:Bicuspid; D003188:Composite Resins; D003731:Dental Caries; D003737:Dental Cavity Preparation; D003763:Dental Leakage; D006801:Humans; D053844:Lasers, Solid-State
chemical_list: D003188:Composite Resins