title: Depth of cure of sealants polymerized with high-power light emitting diode curing lights.
abstract: OBJECTIVE
  To determine whether recommended short curing times of three high-power light emitting diode (LED) curing lights are sufficient to polymerize sealant materials.
  
  
  METHODS
  Opaque-unfilled sealant (Delton LC Opaque), opaque-filled sealant (UltraSeal XT plus), and clear-filled sealant (FluroShield) were light cured in a covered slot-mold using the manufacturers' shortest recommended curing times with three high-power LED lights (3-s VALO, 5-s Fusion, 10-s Smartlite). A 40-s cure with a quartz-tungsten halogen (QTH) light was used as control. Vickers hardness was measured 24 h after curing at the sealant surface and through the depth (0.5 mm increments) (N = 10). Results were analyzed with two-way anova (pair-wise multiple comparisons, significance level 0.05).
  
  
  RESULTS
  The high-power LEDs did not cure the sealants as deep as the QTH. Delton LC Opaque showed the least depth of cure as hardness values beyond a depth of 0.5 mm were not measurable regardless of the curing light. Even for UltraSeal XT plus, when surface hardness was about the same with all lights, hardness decreased more rapidly with depth for the LEDs. FluroShield showed the slowest decline in hardness through the depth for all lights.
  
  
  CONCLUSIONS
  Manufacturers' recommendations for shortest possible curing time with high-power LEDs were not sufficient for adequate polymerization of the tested sealants.
authors.affiliation: Department of Pediatric Dentistry, College of Dentistry, University of Tennessee Health Science Center, Memphis, TN, USA.
authors.forename: Brandon
authors.initials: B
authors.lastname: Kitchens
authors.forename: Martha
authors.initials: M
authors.lastname: Wells
authors.forename: Daranee
authors.initials: D
authors.lastname: Tantbirojn
authors.forename: Antheunis
authors.initials: A
authors.lastname: Versluis
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D055117:Curing Lights, Dental; D004867:Equipment Design; D008422:Materials Testing; D010895:Pit and Fissure Sealants / Q000737:chemistry*; D058105:Polymerization; D011140:Polyurethanes / Q000737:chemistry; D013499:Surface Properties
chemical_list: D003188:Composite Resins; D010895:Pit and Fissure Sealants; D011140:Polyurethanes; C106663:Ultra Seal XT; C086661:Fluoroshield; D017438:Bisphenol A-Glycidyl Methacrylate