title: Temperature rise during polymerization of different cavity liners and composite resins.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the thermal insulating properties of different light curing cavity liners and composite resins during light emitting diode (LED) curing.
  
  
  METHODS
  Sixty-four dentin discs, 1 mm thick and 8 mm in diameter, were prepared. Specimens were divided into four groups. Calcium hydroxide (Ca[OH]2), resin-modified glass ionomer cement, flowable composite and adhesive systems were applied to dentin discs according to the manufacturers' instructions. The rise in temperature during polymerization with a LED curing unit (LCU) was measured using a K-type thermocouple connected to a data logger. Subsequently, all specimens were randomly divided into one of two groups. A silorane-based composite resin and a methacrylate-based composite resin were applied to the specimens. Temperature rise during polymerization of composite resins with LCU were then measured again. Data were analyzed using one-way ANOVA and post hoc Tukey analyses.
  
  
  RESULTS
  There were significant differences in temperature rise among the liners, adhesives, and composite resins (P < 0.05). Silorane-based composite resin exhibited significantly greater temperature rises than methacrylate-based resin (P < 0.05). The smallest temperature rises were observed in Ca(OH)2 specimens.
  
  
  CONCLUSIONS
  Thermal insulating properties of different restorative materials are important factors in pulp health. Bonding agents alone are not sufficient to protect pulp from thermal stimuli throughout curing.
authors.affiliation: Department of Restorative Dentistry, Atatürk University, Erzurum, Turkey.
authors.forename: Ozcan
authors.initials: O
authors.lastname: Karatas
authors.affiliation: Department of Restorative Dentistry, Atatürk University, Erzurum, Turkey.
authors.forename: Verda
authors.initials: V
authors.lastname: Turel
authors.affiliation: Department of Restorative Dentistry, Atatürk University, Erzurum, Turkey.
authors.forename: Yusuf Ziya
authors.initials: YZ
authors.lastname: Bayindir
keywords: Curing unit; dentin; thermal insulation