Bond Strength and Tubule Penetration of Tertiary Monoblock Obturation Systems

Methods: Recently extracted single rooted 72 human teeth were used in this study.  All teeth were decoronised and prepared by RaCe rotary Ni-Ti file system. 40 of the prepared roots were randomly selected for bond strength test and assigned into 4 groups as follow; Group 1: EndoRez, Group 2: Activ GP, Group 3: Smartseal, Group 4: AH 26. After filling of the root canals and complete setting of the materials, 2 slices in 1mm thickness were obtained from coronal third of the roots (n=20) and push out test was performed via a universal testing machine (INSTRON). Remaining 32 roots were assigned into 4 groups as in the manner previously described (n=8). Root canal sealers of each group were marked with Rhodamin B and the root canals were filled. After the complete seting of the materials, slices in 1mm thickness obtained from the middle third of the root  and were imaged under confocal laser scanning microscope. Dentine tubule penetration depth, area and percentage of the root canal sealers were measured on the images. The data were analysed by Kruskall-Wallis and Dunn’s Tests. 

Results: EndoRez showed the lowest bond strength values (p<0,05) while, no significant difference was found amongst the other groups. The lowest penetration depth and area was found in Smartseal group (p<0,05) but no significant difference was found amongst the groups in terms of percentage of dentine tubule penetration (p>0,05).

Conclusions: Different tertiary monoblock systems showed similar bond strength to each other but lower than AH 26. Smartseal showed the lowest dentine tubule penetration area and depth.