title: Push-out bond strength and SEM evaluation of new polymeric root canal fillings.
abstract: OBJECTIVE
  The objective of this study was to compare the interfacial strengths and failure modes of new polymeric endodontic obturation systems consisting of different material combinations.
  
  
  METHODS
  Extracted human single-rooted teeth (n = 105) were instrumented using HERO Shaper rotary instruments and obturated with different combinations of core and sealer as follows: group 1, RealSeal/Resilon; group 2, RealSeal/Herofill; group 3, Hybrid Root Seal/Resilon; group 4, Hybrid Root Seal/Herofill; group 5, MM-Seal/Resilon; group 6, MM-Seal/Herofill; group 7 (control). Failure modes of root slices (1.00 +/- 0.05-mm thick) after push-out testing were examined with stereomicroscope and scanning electron microscopy.
  
  
  RESULTS
  Hybrid Root Seal/Resilon combination had significantly greater bond strength than all the other groups (P < .001); RealSeal/Resilon combination proved to have the second highest bond strength (P < .001). Bond failure was mainly mixed failure in both adhesive and cohesive modes at the dentin/sealer interface.
  
  
  CONCLUSIONS
  The push-out bond strengths of methacrylate-based sealers (Hybrid Root Seal and RealSeal) and thermoplastic synthetic-polymer-based core material (Resilon) combinations were higher than epoxy-resin-based sealer (MM-Seal) and gutta-percha (Herofill) combination.
authors.affiliation: Department of Endodontics, Baskent University School of Dentistry, Ankara, Turkey. eonay@baskent.edu.tr
authors.forename: Emel Olga
authors.initials: EO
authors.lastname: Onay
authors.forename: Mete
authors.initials: M
authors.lastname: Ungor
authors.forename: Hale
authors.initials: H
authors.lastname: Ari
authors.forename: Sema
authors.initials: S
authors.lastname: Belli
authors.forename: Ersin
authors.initials: E
authors.lastname: Ogus
mesh_terms: D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003786:Dental Pulp Cavity / Q000648:ultrastructure; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D006801:Humans; D012387:Root Canal Filling Materials / Q000737:chemistry*; D012389:Root Canal Obturation; D013314:Stress, Mechanical
chemical_list: D003188:Composite Resins; C511498:Real Seal composite resin; D012387:Root Canal Filling Materials; C486892:resilon sealer