title: Sealing properties of one-step root-filling fibre post-obturators vs. two-step delayed fibre post-placement.
abstract: OBJECTIVE
  The sealing properties of a one-step obturation post-placement technique consisting of Resilon-capped fibre post-obturators were compared with a two-step technique based on initial Resilon root filling following by 24h-delayed fibre post-placement.
  
  
  METHODS
  Thirty root segments were shaped to size 40, 0.04 taper and filled with: (1) InnoEndo obturators; (2) Resilon/24h-delayed FibreKor post-cementation. Obturator, root filling and post-cementation procedures were performed using InnoEndo bonding agent/dual-cured root canal sealer. Fluid flow rate through the filled roots was evaluated at 10psi using a computerised fluid filtration model before root resection and after 3 and 9mm apical resections. Fluid flow data were analysed using two-way repeated measures ANOVA and Tukey test to examine the effects of root-filling post-placement techniques and root resection lengths on fluid leakage from the filled canals (alpha=0.05).
  
  
  RESULTS
  A significantly greater amount of fluid leakage was observed with the one-step technique when compared with two-step technique. No difference in fluid leakage was observed among intact canals and canals resected at different lengths for both materials.
  
  
  CONCLUSIONS
  The seal of root canals achieved with the one-step obturator is less effective than separate Resilon root fillings followed by a 24-h delay prior to the fibre post-placement. Incomplete setting of the sealer and restricted relief of polymerisation shrinkage stresses may be responsible for the inferior seal of the one-step root-filling/post-restoration technique.
authors.affiliation: Department of Surgery, University of Zaragoza, Huesca, Spain. fmontice@unizar.es
authors.forename: Francesca
authors.initials: F
authors.lastname: Monticelli
authors.forename: Raquel
authors.initials: R
authors.lastname: Osorio
authors.forename: Manuel
authors.initials: M
authors.lastname: Toledano
authors.forename: Marco
authors.initials: M
authors.lastname: Ferrari
authors.forename: David H
authors.initials: DH
authors.lastname: Pashley
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
mesh_terms: D001047:Apicoectomy / Q000379:methods; D002484:Cementation / Q000379:methods; D003188:Composite Resins / Q000737:chemistry; D003763:Dental Leakage / Q000145:classification; D003764:Dental Materials / Q000737:chemistry*; D017267:Dental Prosthesis Design; D003786:Dental Pulp Cavity / Q000473:pathology; D003804:Dentin / Q000473:pathology; D005898:Glass / Q000737:chemistry; D006801:Humans; D006813:Humidity; D055115:Light-Curing of Dental Adhesives; D010539:Permeability; D011108:Polymers / Q000737:chemistry; D011176:Post and Core Technique / Q000295:instrumentation*; D012212:Rheology; D012387:Root Canal Filling Materials / Q000627:therapeutic use*; D012389:Root Canal Obturation / Q000379:methods*; D018915:Root Canal Preparation / Q000379:methods; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors
chemical_list: D003188:Composite Resins; D003764:Dental Materials; C113550:FiberKor, sculpture; D011108:Polymers; D012387:Root Canal Filling Materials; C009753:fiberglass; C486892:resilon sealer