title: Depth of cure and microleakage with high-intensity and ramped resin-based composite curing lights.
abstract: BACKGROUND
  The authors conducted a study to determine whether high-intensity curing lights in high and ramped intensity modes affect microleakage of resin-based composite restorations and whether different types of resin-based composites meet American National Standards Institute/American Dental Association Specification no. 27 (1993): 7.7 for depth of cure when polymerized using these lights.
  
  
  METHODS
  The authors compared five high-intensity lights, three plasma arc lights and two quartz-tungsten-halogen lights in their regular and ramped intensity modes with a quartz-tungsten-halogen 40-second light. The parameters tested were microleakage one month after bonding and curing depth for different resin-based composite types. The authors measured curing depth using a scratch test.
  
  
  RESULTS
  Light curing with Optilux 501 (Kerr/Demetron, Orange, Calif.) for 10 seconds and ADT Power PAC (American Dental Technologies, Corpus Christi, Texas) for 10 seconds resulted in higher microleakage values than light curing with other lights (P < .05). The microhybrid resin-based composite was the only material that met the specification when light cured with all of the lights tested. The flowable resin-based composite did not meet the specification when light cured with all lights tested. Microhybrid resin-based composite had the greatest depth of cure, and flowable resin-based composite had the least depth of cure.
  
  
  CONCLUSIONS
  Microhybrid resin-based composite microleakage is affected by some light-curing modes. Different categories of resin-based composites are cured to different depths using high-intensity lights.
  
  
  CONCLUSIONS
  Light curing with some high-intensity lights compared with halogen lights may result in higher microleakage values. Use caution when light curing flowable resin-based composite with the high-intensity lights. Place increments less than 2 millimeters in depth when using this material.
authors.affiliation: Department of Restorative Dentistry, Southern Illinois University School of Dental Medicine, Alton 62002, USA. pjain@siue.edu
authors.forename: Poonam
authors.initials: P
authors.lastname: Jain
authors.forename: Adam
authors.initials: A
authors.lastname: Pershing
mesh_terms: D000704:Analysis of Variance; D017609:Barium Compounds / Q000737:chemistry / Q000528:radiation effects; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry / Q000528:radiation effects; D003188:Composite Resins / Q000737:chemistry* / Q000528:radiation effects; D001840:Dental Bonding; D003763:Dental Leakage / Q000145:classification*; D003793:Dental Restoration, Permanent / Q000295:instrumentation*; D006219:Halogens; D006801:Humans; D008029:Lighting / Q000295:instrumentation*; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry / Q000528:radiation effects; D011791:Quartz; D012822:Silicon Dioxide / Q000737:chemistry / Q000528:radiation effects; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013997:Time Factors; D014414:Tungsten
chemical_list: C121035:Aeliteflo; D017609:Barium Compounds; D003188:Composite Resins; C466112:Esthet-X; D006219:Halogens; D011108:Polymers; C099128:Prodigy; C477351:Prodigy Condensable; D011791:Quartz; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide; D014414:Tungsten