title: Effect of post-cure temperature and heat duration on monomer conversion of photo-activated dental resin composite.
abstract: OBJECTIVE
  This research evaluated the relationship between post-cure heating temperature and duration on the monomer conversion of a commercial light-activated resin composite.
  
  
  METHODS
  Disc-shaped composite specimens (10 x 1 mm) were initially light-cured and then submitted to one of the following post-cure.
  
  
  CONCLUSIONS
  None (control), 50 degrees, 75 degrees, 100 degrees or 125 degrees C for 0.5, 1, 3, 5, or 7 min. After curing, specimens were stored in the dark at room temperature. Monomer conversion of all specimens was then determined using infrared spectroscopy.
  
  
  RESULTS
  Post-cure temperature was 12 times more influential than was heal duration on the extent of resin cure. The extent of cure increased linearly with an increase in post-cure temperature. Post-cure specimens that were heated between 3 and 7 min demonstrated equivalent cure values. All post-cure healing conditions resulted in significantly higher cure values than the light-cured only control.
  
  
  CONCLUSIONS
  Physical properties of post-cure heated composites may change with respect to aging and water, but monomer conversion values of post-cure heated materials remain unaltered. Results of this study validate the use of relatively high temperatures for increasing the extent of monomer conversion. Such increases may lead to more biocompatible restorations.
authors.affiliation: Department of Conservative Dentistry, University of Ankara School of Dentistry, Ankara, Turkey.
authors.forename: Y H
authors.initials: YH
authors.lastname: Bağis
authors.forename: F A
authors.initials: FA
authors.lastname: Rueggeberg
mesh_terms: D000704:Analysis of Variance; D001672:Biocompatible Materials / Q000737:chemistry; D002244:Carbon / Q000737:chemistry; D003188:Composite Resins / Q000032:analysis / Q000737:chemistry*; D003764:Dental Materials / Q000032:analysis / Q000737:chemistry*; D006358:Hot Temperature; D006801:Humans; D008027:Light; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry; D019279:Resin Cements / Q000032:analysis / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013223:Statistics as Topic; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D003188:Composite Resins; D003764:Dental Materials; D011108:Polymers; D019279:Resin Cements; D014867:Water; C065770:Herculite XR; D002244:Carbon