title: The effect of a translucent post on resin composite depth of cure.
abstract: OBJECTIVE
  To evaluate the effect of a light-transmitting post on the depth of cure of a resin composite.
  
  
  METHODS
  Acetate resin molds were filled with resin composite in which a light-transmitting post was inserted into the center and photopolymerized to the manufacturer's recommendations. Identical molds without a light-transmitting post were photopolymerized in a similar matter and served as a control. Molds were sectioned on a water-cooled, diamond saw at prescribed distances and the depth of cure was determined using a Knoop Hardness bottom-to-top ratio criterion. Data within each group were analyzed using 2-way (depth-by-distance) repeated measure ANOVA. Between-group contrasts (post versus no post) were accessed by a 3-way (2 within-subjects and 1 between-subjects) ANOVA with critical p = 0.05.
  
  
  RESULTS
  The presence of the post did increase (p < 0.001) Knoop Hardness values in simulated apical regions as compared to a control. However, there was no difference in the depth of cure between the groups (3-way analysis p = 0.2) and also when evaluated using an 80% bottom-to-top Knoop Hardness ratio.
  
  
  CONCLUSIONS
  The results suggest that these posts may have a limited utility when judged against a Knoop Hardness ratio criterion.
authors.affiliation: United States Air Force Dental Investigation Service, Det 1 USAFSAM, 310C B Street, Building 1H, Great Lakes, IL 60088, USA. howard.roberts@ndri.med.navy.mil
authors.forename: Howard W
authors.initials: HW
authors.lastname: Roberts
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Leonard
authors.forename: Kraig S
authors.initials: KS
authors.lastname: Vandewalle
authors.forename: Mark E
authors.initials: ME
authors.lastname: Cohen
authors.forename: David G
authors.initials: DG
authors.lastname: Charlton
mesh_terms: D000704:Analysis of Variance; D003188:Composite Resins / Q000528:radiation effects*; D005898:Glass; D006244:Hardness; D008027:Light; D008422:Materials Testing; D044367:Phase Transition; D011176:Post and Core Technique; D012822:Silicon Dioxide / Q000528:radiation effects*; D015040:Zirconium / Q000528:radiation effects*
chemical_list: D003188:Composite Resins; C083568:Z100 composite resin; C009753:fiberglass; D012822:Silicon Dioxide; D015040:Zirconium