title: Effect of Curing Light Barriers and Light Types on Radiant Exposure and Composite Conversion.
abstract: OBJECTIVE
  Previous research investigated the effects of curing tip barriers on light output and composite properties, but no study has measured the effect of a wide variety of barriers and curing light types on delivered radiant exposure and the resulting composite cure 2 mm below the radiated surface.
  
  
  METHODS
  Six barrier materials and six curing light types were tested. Spectroradiometry was used to measure irradiance with and without barriers for each light type, and radiant exposure values were determined for a commercial camphorquinone-based dental composite material. Composite monomer conversion was measured at 10 minutes following exposure for each light type/barrier condition (N = 5) using infrared spectroscopy. Results were subjected to one-way analyses of variance for radiant exposure and conversion among barrier types within a given curing light: preset alpha 0.05.
  
  
  RESULTS
  All barriers significantly reduced radiant exposure compared with the uncovered tip, but the use of the two polywave LEDs covered with a latex-based barrier demonstrated significantly lower conversion values.
  
  
  CONCLUSIONS
  Although light-curing barriers reduce radiant exposure to a restorative material over a recommended exposure, this reduction is not sufficient to cause significant reduction in composite cure, except when using a latex-based barrier and a polywave LED curing light.
  
  
  CONCLUSIONS
  Clinicians need to be aware of the possible interaction between curing light barriers and curing light type in order to optimally photocure restorative materials.
authors.affiliation: Department of Oral Rehabilitation, Georgia Regents University, Augusta, GA, USA.
authors.forename: Rhoda Joyner
authors.initials: RJ
authors.lastname: Sword
authors.affiliation: Kennesaw, GA, USA.
authors.forename: Uyen Ngoc
authors.initials: UN
authors.lastname: Do
authors.affiliation: Atlanta, GA, USA.
authors.forename: Jonathan Hu
authors.initials: JH
authors.lastname: Chang
authors.affiliation: Department of Oral Rehabilitation, Georgia Regents University, Augusta, GA, USA.
authors.forename: Frederick Allen
authors.initials: FA
authors.lastname: Rueggeberg
mesh_terms: D003188:Composite Resins; D055117:Curing Lights, Dental; D003764:Dental Materials
chemical_list: D003188:Composite Resins; D003764:Dental Materials