Push-out bond strength and SEM evaluation of new polymeric root canal fillings.
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.
Onay
Emel Olga
EO
Department of Endodontics, Baskent University School of Dentistry, Ankara, Turkey. eonay@baskent.edu.tr
Ungor
Mete
M
Ari
Hale
H
Belli
Sema
S
Ogus
Ersin
E
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
D003188:Composite Resins; C511498:Real Seal composite resin; D012387:Root Canal Filling Materials; C486892:resilon sealer