title: Microleakage of glass ionomer restoration in cavities prepared by Er,Cr:YSGG laser irradiation in primary teeth.
abstract: OBJECTIVE
  The purpose of this study was to evaluate microleakage of cavity preparation in primary teeth made with an Er, Cr:YSGG laser (L) or high-speed drill (HD) and conventional (CGIC) and resin-modified glass ionomer cement (RMGIC).
  
  
  METHODS
  One hundred primary teeth were divided into 10 groups (N=10): (a) groups 1 and 2 represented cavities prepared by a no. 1012 diamond bur with HD; (b) groups 3 through 10 represented cavities prepared with an Er, Cr:YSGG laser (with a repetition rate of 20 Hz power settings varying for enamel=2.5 W and 3 W and dentine=1.0 W and 1.5 W). After cavity preparation, samples were restored with CGIC (Ketac Molar Easy Mix) and RMGIC (Vitremer), impermeabilized, thermal cycled, stained, washed, and sectioned. The degree of dye penetration was scored by 3 standardized examiners using a light stereoscope at X30 magnification.
  
  
  RESULTS
  The Kruskal-Wallis test detected no statistical differences between the cavity preparation methods (P<.049). Neither of the GICs tested were able to avoid microleakage, and the RMGIC showed the lowest statistical degree of microleakage compared with CGIC for both types of cavity preparation.
  
  
  CONCLUSIONS
  The Er,Cr:YSGG laser provided an equivalent method of cavity preparation compared to the high-speed drill. The resin-modified glass ionomer cement showed the lowest degree of microleakage. This restorative material should be considered when choosing the cavity preparation method.
authors.affiliation: Professional Master Course of Lasers in Dentistry, School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Rively Rodrigues
authors.initials: RR
authors.lastname: Rossi
authors.forename: Ana Cecília
authors.initials: AC
authors.lastname: Aranha
authors.forename: Carlos de Paula
authors.initials: Cde P
authors.lastname: Eduardo
authors.forename: Lisiane Soares
authors.initials: LS
authors.lastname: Ferreira
authors.forename: Ricardo S
authors.initials: RS
authors.lastname: Navarro
authors.forename: Denise Maria
authors.initials: DM
authors.lastname: Zezell
mesh_terms: D004396:Coloring Agents; D003188:Composite Resins / Q000737:chemistry; D003737:Dental Cavity Preparation / Q000295:instrumentation / Q000379:methods*; D003743:Dental Enamel / Q000473:pathology / Q000601:surgery; D003754:Dental High-Speed Equipment; D003763:Dental Leakage / Q000145:classification*; D003775:Dental Polishing; D003793:Dental Restoration, Permanent / Q000379:methods*; D003804:Dentin / Q000473:pathology / Q000601:surgery; D018130:Diamond / Q000737:chemistry; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D053685:Laser Therapy / Q000379:methods*; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008422:Materials Testing; D019279:Resin Cements / Q000737:chemistry; D013696:Temperature; D013997:Time Factors; D014094:Tooth, Deciduous / Q000473:pathology / Q000601:surgery*; D014867:Water / Q000737:chemistry
chemical_list: D004396:Coloring Agents; D003188:Composite Resins; D005899:Glass Ionomer Cements; C515713:Ketac Molar Easymix; D019279:Resin Cements; C084550:Vitremer; D014867:Water; D018130:Diamond