title: Effect of thermocycling and varying polymerization techniques on the restorative interface of class V cavities restored with different composite resin systems.
abstract: BACKGROUND
  To evaluate marginal microleakage of two composite resins - a methacrylate- and a silorane-based submitted to different polymerization techniques and thermocycling.
  
  
  METHODS
  Ninety-six class V cavities were prepared in sound human molars and restored under different polymerization and thermocycling regimens. The adhesive systems employed were Adper Scotchbond Multipurpose and Filtek P-90 for cavities restored with Z250 and P-90. The specimens were restored with Z250 or P-90, and divided into 3 subgroups with different polymerization techniques. The data were analyzed by Three way Analysis of Variance Test (p<0.05).
  
  
  RESULTS
  Micro infiltration lower scores were found in groups which were used silorane-based resin with significant statistical difference compared with the specimens restored with methacrylate-based resin, independently of polymerization type used and thermocycling (P>0.001).
  
  
  CONCLUSIONS
  Silorane-based composite resins present lower marginal microleakage values when compared to methacrylate-based composites resins.Key words:Composite resin, microleakage, polymerization.
authors.affiliation: DDS, MSc, PhD, Department of Prosthodontics, University of Southern Santa Catarina, Tubarão, Santa Catarina, Brazil.
authors.forename: Jefferson-Ricardo
authors.initials: JR
authors.lastname: Pereira
authors.affiliation: DDS, Department of Prosthodontics, University of Southern Santa Catarina, Tubarão, Santa Catarina, Brazil.
authors.forename: Lindomar-Corrêa
authors.initials: LC
authors.lastname: Júnior
authors.affiliation: DDS, MSc, PhD, Department of Conservative Dentistry, Rio Grande do Sul Federal University, Porto Alegre, RS, Brazil.
authors.forename: Marcus-Vinicius-Reis
authors.initials: MV
authors.lastname: Só
authors.affiliation: DDS, MSc, Newton Fahl Center, Curitiba, PR, Brazil.
authors.forename: Newton-Fahl
authors.initials: NF
authors.lastname: Júnior