title: EFFECT OF LIGHT INTENSITY ON THE CURE CHARACTERISTICS OF PHOTO-POLYMERISED DENTAL COMPOSITES.
abstract: OBJECTIVE
  To determine the light intensity emitted by light curing units (LCUs) and its effect on the cure characteristics of composites polymerised with it.
  
  
  METHODS
  A laboratory based cross sectional study.
  
  
  METHODS
  Public and private dental clinics in Nairobi, Kenya.
  
  
  RESULTS
  Thirty five (42.17%) LCUs produced light of intensity ≤300mWcm⁻² while 43 (51.8%) LCUs had their intensities between 300 and 1200mWcm⁻². Mean DOC and surface hardness for the 0-300mWcm⁻² LCUs was 1.34mm and 46.60VHN respectively. The mean DOC increased steadily from the lowest intensity group (1.34mm) to the 1200-15OOmWcm⁻² group (2.32 mm) and then declined to 1.98mm for the 1500-1800mWcm⁻² group. Statistical analysis showed significant differences in the mean DOC (p=0.000) and surface micro-hardness (p=0.002) for the different intensity groups.
  
  
  CONCLUSIONS
  Light intensity output of LCUs has a significant influence on the cure characteristics of dental composites with both DOC and surface micro-hardness increasing with increase in light intensity up to 1500mWcm⁻².
authors.affiliation: Department of Conservative and Prosthetic Dentistry, College of Health Sciences, University of Nairobi, Nairobi, Kenya.
authors.forename: B A
authors.initials: BA
authors.lastname: Kassim
authors.forename: B K
authors.initials: BK
authors.lastname: Kisumbi
authors.forename: W R
authors.initials: WR
authors.lastname: Lesan
authors.forename: L W
authors.initials: LW
authors.lastname: Gathece
mesh_terms: D003188:Composite Resins / Q000528:radiation effects*; D003430:Cross-Sectional Studies; D055117:Curing Lights, Dental; D003748:Dental Equipment; D006244:Hardness; D006801:Humans; D011829:Radiation Dosage
chemical_list: D003188:Composite Resins