title: In vitro pulp chamber temperature rise from irradiation and exotherm of flowable composites.
abstract: OBJECTIVE
  The aim of this study was to investigate the pulpal temperature rise induced during the polymerization of flowable and non-flowable composites using light-emitting diode (LED) and halogen (quartz-tungsten-halogen) light-curing units (LCUs).
  
  
  METHODS
  Five flowable and three non-flowable composites were examined. Pulpal temperature changes were recorded over 10 min in a sample primary tooth by a thermocouple. A conventional quartz-tungsten-halogen source and two LEDs, one of which was programmable, were used for light curing the resin composites. Three repetitions per material were made for each LCU.
  
  
  RESULTS
  There was a wide range of temperature rises among the materials (P < 0.05). Temperature rises ranged between 1.3 degrees C for Filtek Supreme irradiated by low-power LED and 4.5 degrees C for Grandio Flow irradiated by high-power LED. The highest temperature rises were observed with both the LED high-power and soft-start LCUs. The time to reach the exothermic peak varied significantly between the materials (P < 0.05).
  
  
  CONCLUSIONS
  Pulpal temperature rise is related to both the radiant energy output from LCUs and the polymerization exotherm of resin composites. A greater potential risk for heat-induced pulp damage might be associated with high-power LED sources. Flowable composites exhibited higher temperature rises than non-flowable materials, because of higher resin contents.
authors.affiliation: Department of Paediatric Dentistry, School of Dentistry, University of Al-Baath, Hama, Syria. d_kusai@yahoo.co.uk
authors.forename: Kusai
authors.initials: K
authors.lastname: Baroudi
authors.forename: Nick
authors.initials: N
authors.lastname: Silikas
authors.forename: David C
authors.initials: DC
authors.lastname: Watts
mesh_terms: D001831:Body Temperature / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D003188:Composite Resins / Q000737:chemistry* / Q000528:radiation effects; D055117:Curing Lights, Dental / Q000145:classification; D003764:Dental Materials / Q000737:chemistry* / Q000528:radiation effects; D003782:Dental Pulp / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D008963:Molar / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D011108:Polymers / Q000737:chemistry / Q000528:radiation effects; D013821:Thermometers; D013997:Time Factors; D014094:Tooth, Deciduous / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects
chemical_list: D003188:Composite Resins; D003764:Dental Materials; C467913:Filtek Flow; C474035:Filtek Supreme; C444701:Filtek Z250; C509998:Grandio; D011108:Polymers; C102735:Revolution (composite resin); C121818:Tetric ceram; C451741:point 4 composite resin; C452226:tetric flow composite resin