Inclusion criteria | 1. Participants: Freshly extracted single rooted human teeth with closed apices, and after standard root canal preparation, all specimens had regular space for obturation. |
2. Intervention: Root canals were obturated with Gutta-percha/AH plus and (or) the Resilon system. | |
3. Control: Unprepared and unfilled roots (negative control roots) or prepared but unfilled roots (positive control roots). | |
4. Outcomes: Vertical fracture resistance of roots. | |
5. Study design: Randomized controlled in vitro trials. | |
Exclusion criteria | 1. Studies that did not fulfill the inclusion criteria. |
2. .Studies that evaluated the influence of different factors on the resistance to fracture of endodontically treated roots obturated with Gutta-percha/AH plus or the Resilon system. | |
3. Retreatment. |