title: Temperature changes caused by light curing of fiber-reinforced composite resins.
abstract: OBJECTIVE
  The aim of the study is to evaluate temperature change in fiber-reinforced composite (FRC) resin photopolymerized with a light-emitting diode (LED) light-curing unit (LCU).
  
  
  METHODS
  Forty dentine disks (1 mm thick and 8 mm diameter) were prepared from human molars. The FRC specimens (2 mm thickness and 8 mm diameter) consisted of polyethylene fiber (Construct (CT)) products or glass fiber (ever Stick (ES)) and one hybrid composite bonded to the dentin disks and polymerized with an LED LCU. Control groups were prepared using the hybrid composite. Temperature rise in dentine samples under the FRC bonded disks was measured using a K-type thermocouple, and data were recorded. Temperature change data were subjected to analysis of variance (ANOVA) and Duncan's test.
  
  
  RESULTS
  The results show that addition of fiber (one or two layers) did not change temperature rise values at any of the exposure times (P > 0.05). The CT fiber/two layer/40 s group exhibited the greatest temperature rise (5.49 ± 0.62) and the ES/one layer/10 s group the lowest rise (1.75 ± 0.32). A significant difference was observed in temperature rise measured during 10 and 20 s exposures (P < 0.05).
  
  
  CONCLUSIONS
  Maximal temperature rise determined in all groups was not critical for pulpal health, although clinicians need to note temperature rises during polymerization.
authors.affiliation: Department of Restorative Dentistry, University of Atatürk, Erzurum, Turkey.
authors.forename: Nurcan Ozakar
authors.initials: NO
authors.lastname: Ilday
authors.affiliation: Department of Restorative Dentistry, University of Atatürk, Erzurum, Turkey.
authors.forename: Omer
authors.initials: O
authors.lastname: Sagsoz
authors.affiliation: Department of Restorative Dentistry, University of Atatürk, Erzurum, Turkey.
authors.forename: Ozcan
authors.initials: O
authors.lastname: Karatas
authors.affiliation: Department of Restorative Dentistry, University of Atatürk, Erzurum, Turkey.
authors.forename: Yusuf Ziya
authors.initials: YZ
authors.lastname: Bayindir
authors.affiliation: Department of Restorative Dentistry, University of Atatürk, Erzurum, Turkey.
authors.forename: Neslihan
authors.initials: N
authors.lastname: Çelik
keywords: Dentin; fiber-reinforced composite; polymerization; temperature rise