title: Macromolecular leakage beneath complete cast crowns. A 6-month in vitro investigation using microfluorimetry.
abstract: OBJECTIVE
  This investigation evaluated the leakage (diffusion) of lipopolysaccharide and dextran beneath cast-gold crowns luted with one of three cements.
  
  
  METHODS
  Thirty extracted molars were prepared for crowns. Thirty crowns with access ports (facial or lingual) were cast in gold and luted to their preparations with zinc phosphate, glass-ionomer, or an adhesive resin cement (10 per group). Teeth and crowns with filters inserted in the ports were immersed in a solution of labeled macromolecules (tetramethylrhodamine isothiocyanate-labeled lipopolysaccharide and fluorescein isothiocyanate-labeled-dextran) and evaluated for leakage at 2 weeks and 1, 2, 3, 4, 5, and 6 months. Filters were retrieved and analyzed with microfluorimetry.
  
  
  RESULTS
  No filters retrieved from any crowns demonstrated any detectable leakage, and all filters were negative for both dextran and lipopolysaccharide for all evaluation periods.
  
  
  CONCLUSIONS
  For the 6 months of this investigation, zinc phosphate, glass-ionomer, and adhesive resin cements were equally effective at preventing leakage of detectable molecular concentrations of lipopolysaccharide and dextran to the level of the access ports in the absence of thermal or mechanical stress.
authors.affiliation: Division of Reconstructive and Comprehensive Care, New York University, College of Dentistry, 345 East 24th Street, New York, New York 10010, USA. ajc1@is3.nyu.edu
authors.forename: A J
authors.initials: AJ
authors.lastname: Coleman
authors.forename: H H
authors.initials: HH
authors.lastname: Rickerby
authors.forename: L R
authors.initials: LR
authors.lastname: Antonoff
mesh_terms: D002484:Cementation; D003442:Crowns; D003763:Dental Leakage / Q000175:diagnosis*; D003911:Dextrans / Q000032:analysis; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D005470:Fluorometry; D005899:Glass Ionomer Cements; D006801:Humans; D008070:Lipopolysaccharides / Q000032:analysis; D008963:Molar; D019279:Resin Cements; D012235:Rhodamines; D015036:Zinc Phosphate Cement
chemical_list: D003911:Dextrans; D005456:Fluorescent Dyes; D005899:Glass Ionomer Cements; D008070:Lipopolysaccharides; D019279:Resin Cements; D012235:Rhodamines; C009434:tetramethylrhodamine isothiocyanate; D015036:Zinc Phosphate Cement; D016650:Fluorescein-5-isothiocyanate