title: The effect of different light-curing methods on temperature changes of dual polymerizing agents cemented to human dentin.
abstract: OBJECTIVE
  This in vitro study aims to measure the temperature changes of resin luting cements cemented to human dentin when using different light curing systems for photo-activation.
  
  
  METHODS
  The three different types of light-curing units (LCUs) used for photoactivation were quartz-tungsten halogen (QTH), light emitting diode (LED), and plasma arc (PAC). Two types of dual cure resin cements were used [Variolink II (VL) and Choice (CH)]. Feltik Z250 composite resin material was used to prepare composite discs. Thirty human dentin specimens were prepared for each resin luting cement (ten for each light source). A total of 60 specimens were fabricated. Resin cement was applied on a dentin bridge and covered with the prepared composite disc where specimens were fabricated. Temperature change was recorded with a digital thermometer.
  
  
  RESULTS
  The lowest temperature was recorded when VL and CH were photo-activated with the PAC unit. The PAC unit produced significantly lower recorded temperatures than the LED and QTH units. No significant difference appeared between QTH and LED units in terms of recorded temperature.
  
  
  CONCLUSIONS
  The PAC unit produced significantly lower temperature changes compared to QTH and LED curing units. The risk for temperature rise should be taken into consideration during photo-polymerization of adhesive resins with LED or QTH in deep cavities when dentin thickness is 0.5 mm.
authors.affiliation: Department of Restorative Dental Sciences of the College of Dentistry at King Saud University in Riyadh, Kingdom of Saudi Arabia. nmataher@hotmail.com
authors.forename: Nadia Malek
authors.initials: NM
authors.lastname: Taher
authors.forename: Yousra
authors.initials: Y
authors.lastname: Al-Khairallah
authors.forename: Sheikha Hamed
authors.initials: SH
authors.lastname: Al-Aujan
authors.forename: Maha
authors.initials: M
authors.lastname: Ad'dahash
mesh_terms: D000704:Analysis of Variance; D001831:Body Temperature; D003188:Composite Resins; D003748:Dental Equipment; D003782:Dental Pulp; D003804:Dentin / Q000033:anatomy & histology; D006219:Halogens; D006801:Humans; D008027:Light; D044367:Phase Transition; D019279:Resin Cements / Q000737:chemistry / Q000528:radiation effects*; D012666:Semiconductors; D014978:Xenon
chemical_list: C086628:Choice resin cement; D003188:Composite Resins; C444701:Filtek Z250; D006219:Halogens; D019279:Resin Cements; C103502:Variolink; D014978:Xenon