title: Microleakage along apical root fillings and cemented posts.
abstract: BACKGROUND
  Coronal leakage of endodontically treated teeth has been found to result in a high failure rate.
  
  
  OBJECTIVE
  This study tested leakage along apical root fillings remaining after post space preparation and cemented posts in root canals.
  
  
  METHODS
  A total of 120 human roots were used in the study and divided into six groups, 20 roots for each group. By using a modified fluid transport model, leakage (in microL/hr) along ParaPost dowels that were cemented in the coronal 7 mm of root canals with Fuji Duet, Ketac Cem, Panavia EX, or zinc phosphate cements was compared with that along the coronal 7 mm of conventional root canal fillings. Leakage along the apical 4 mm of root filling remaining after post space preparation was compared with that along the 11 mm root filling before post space preparation.
  
  
  RESULTS
  More leakage was recorded along the apical 4 mm of root filling than along the 11 mm of original root filling (p = 0.0325). ParaPost dowels cemented with any test cement did not produce more leakage than the 7 mm coronal root filling (p = 0.2145).
  
  
  CONCLUSIONS
  The apical 4 mm of root canal filling remaining after post space preparation leaks statistically significantly more than the original full-length root canal filling. The leakage created by removal of the coronal part of root canal filling during post space preparation may be compensated by the cemented posts.
authors.affiliation: Department of Cariology Endodontology Pedodontology, Academic Center for Dentistry Amsterdam, The Netherlands.
authors.forename: M K
authors.initials: MK
authors.lastname: Wu
authors.forename: Y
authors.initials: Y
authors.lastname: Pehlivan
authors.forename: E G
authors.initials: EG
authors.lastname: Kontakiotis
authors.forename: P R
authors.initials: PR
authors.lastname: Wesselink
mesh_terms: D000704:Analysis of Variance; D003188:Composite Resins; D003763:Dental Leakage / Q000209:etiology* / Q000517:prevention & control; D005899:Glass Ionomer Cements; D006801:Humans; D008277:Magnesium Oxide; D008961:Models, Structural; D010710:Phosphates; D011076:Polycarboxylate Cement; D011176:Post and Core Technique / Q000009:adverse effects*; D019279:Resin Cements; D019233:Retreatment; D012212:Rheology; D012387:Root Canal Filling Materials; D019553:Tooth, Nonvital; D015034:Zinc Oxide; D015036:Zinc Phosphate Cement
chemical_list: D003188:Composite Resins; C113301:FujiPlus; D005899:Glass Ionomer Cements; D010710:Phosphates; D011076:Polycarboxylate Cement; D019279:Resin Cements; D012387:Root Canal Filling Materials; D008277:Magnesium Oxide; D015036:Zinc Phosphate Cement; C040235:Ketac-cem; C052304:Panavia EX; D015034:Zinc Oxide