Effect of cyclic-loading on sealing and quality of root-end filling-materials

Methods: Dimentionally similar one hundered twelve human maxillary central incisor teeth were selected. The root canals were filled using single-cone technique and root-ends were resected. Root-end cavities were ultrasonically prepared with diamond coated retrotips. The teeth were divided into seven groups (n=16) and root-end cavities were filled with ProRoot MTA, Super EBA, IRM, Vitrabond, Geristore, composite resin and TechBiosealer Root End. Each tooth was measured with fluid filtration device before and after mechanical cyclic loading (50x10³, 50 N, 0,2 Hz) to test a possible leakage and the results were calculated as Lp. Seven teeth of each group were scanned with micro-CT and volume measurement of voids and gaps incidence in the obturated root ends were carried out by using Mimics (Materialise) 10.01 software before and after mechanical loading. The results were analyzed using Oneway ANOVA, Duncan, and Paired t test (p<0,05). 

Results: Before loading, MTA showed least leakage value, Vitrebond showed more leakage than MTA and Geristore (p<0,05). After loading, IRM showed the most leakage value, there was no statistically difference between other groups. (p<0,05). TechBiosealer Root End was the only material which positively affected from loading in terms of leakage (p<0,05).

Conclusions: Mechanical loading does not affect sealing ability of root end filling materials except TechBioselaer Root End. Mechanical loading has not any effect on void incidence.