Push-out bond strength of different root canal obturation materials


Background: The aim of this study was to evaluate the push-out bond strength of four different obturation materialsto intraradicular dentin and to determine the failure mode.Materials and method: forty straight palatal roots of the maxillary first molars teeth were used in this study, the rootswere instrumented using crown down technique and rotary EndoSequence system, the roots were randomly dividedinto four groups according to the materials used for obturation (n=10).Group (1): AH Plus sealer and gutta-percha.Group (2): Activ GP glass ionomer sealer and Activ GP gutta-percha (Activ GP system). Group (3): Bioceramic sealerand Bioceramic gutta-percha. Group (4): GuttaFlow2 sealer and gutta-percha. For all groups single cone obturationtechnique was used. After incubation period of one week, the roots were embedded in clear acrylic resin and eachroot sectioned into three levels apical, middle and cervical. The bond strength was measured using computerizeduniversal testing machine, each section fixed in the machine so that the load applied from apical to coronaldirection at 0.5mm/min speed and the computer drew curve to show the higher bond force before dislodgment ofthe filling material. After de-bonding each sample was examined under Stereomicroscopic and the type of failuremode was recorded.Results: showed a non significant difference between AH plus group and Bioceramic group. AH Plus group showed avery highly significant difference with Activ GP group and a highly significant difference with GuttaFlow2 group.There were significant differences between coronal level and both apical and middle levels with no significantdifferences between apical and middle levels within each group.Conclusion: AH plus group showed the highest mean of bond strength in comparing to other tested groups