Resistance to Vertical Root Fracture of Endodontically Treated Teeth with AH Plus, Endorez and Metaseal

Introduction: The purpose of this in vitro study was to assess the influence of AH Plus, EndoREZ and MetaSEAL, on the resistance to vertical root fracture of endodontically treated teeth when either the matched taper single cone or lateral condensation technique was used. Methods: Eighty extracted single-canal mandibular teeth were sectioned, leaving a standard root length of 13 mm. The buccolingual and mesiodistal diameters were measured, and the teeth were randomly divided into 8 groups (n = 10). There were no statistically significant differences between the groups in terms of the diameters. In group 1, no instrumentation or obturation was performed. The rest of the roots were chemo mechanically prepared with nickel-titanium ProTaper rotary instruments up to size F3 at the working length. Group 2 was left unobstructed. Groups 3 and 4 were obturated with AH Plus used with the matched-taper single-cone and lateral condensation techniques, respectively. In groups 5 and 6 Endorez was used with the matched-taper single-cone and lateral condensation techniques, respectively whereas in groups 7 and 8, MetaSEAL root canal sealer was used with the matched-taper single-cone and lateral condensation techniques, respectively. All of the roots were mounted vertically in self-curing acrylic resin blocks that exposed 8 mm of the coronal part. Then the roots were subjected to a vertical loading force (1 mm/min). The force required to produce a fracture was recorded in newtons. The data were analyzed by using Kruskal?Wallis one way analysis of variance and mann whitney u &wilcoxon w tests. (P < .05). Results: The fracture resistance values of intact and instrumented but not obturated roots was significantly lower than the remaining groups in study. When roots were obturated with matched taper single cone technique, MetaSEAL and AH Plus exhibited statistically significant higher values of fracture resistance than EndoREZ .There was no statistically significant difference in the values of fracture resisitance of AH Plus & MetaSEAL. When lateral condensation technique was used, there was statistically significant difference in the values of AH Plus, EndoREZ & MetaSEAL with AH Plus exhibiting higher values than the latter two. The fracture resistance values of MetaSEAL and EndoREZ were not statistically significant with each other .The values of fracture resistance of MetaSEAL were significantly higher when used with matched taper single cone technique as compared to lateral condensation. Conclusion: When used with the matched-taper single-cone technique, MetaSEAL and AH Plus have the potential to reinforce endodontically treated teeth.