Although the majority of the studies reported that the use of root canal sealers increased the fracture resistance of endodontically treated teeth , conflicting evidence was found for the reinforcing effect of resin , glass ionomer , and calcium silicate-based sealers while there was moderate evidence for zinc oxide eugenol-based sealers in favor of no reinforcing effect .
Conclusion On the basis of available evidence , the use of root canal sealer increases the fracture resistance of endodontically treated teeth .
Regarding the comparisons among the sealers , no conclusions could be drawn for the superiority of one sealer type to another .
Objective The purpose of this study was to systematic ally review and critically analyze the published data of in vitro studies testing the effect of root canal sealers on the fracture resistance of endodontically treated teeth .
Effect of obturating systems, dowel materials, and adhesive luting techniques on the resistance to fracture of endodontically treated teeth.
PURPOSE The aim of this study was to assess the role of obturating systems , dowel material s , and adhesive techniques on the resistance to fracture of endodontically treated teeth . MATERIAL AND METHODS Eighty maxillary central incisors were selected and r and omly divided into two groups according to the obturating system ( n = 40 ) ; group I : gutta-percha and Roeko sealer ; group II : RealSeal . Both groups were further subdivided into two subgroups ; subgroup A : using ceramic dowels ( Cosmopost ) ; subgroup B using fiber dowels ( Easy Post ) . Each subgroup was assigned to two divisions according to the adhesive luting technique ; division V ( total-etch ) Variolink II resin cement ; division U ( self-adhesive ) RelyX Unicem . Composite core build-up was made using a core former . Each specimen was loaded 2 mm from its incisal edge on the palatal side at a 135 ° angle with the long axis of the tooth using a universal testing machine with a load cell of 5 KN at a crosshead speed of 0.5 mm/min until fracture . Failure loads were recorded in N. Scanning electron microscopic examination at the dentin/resin interface ( 1000x ) was performed . Three-way ANOVA was used to test the effect of obturating system , dowel material , adhesive technique , and their interactions ( obturating system * dowel material , obturating system * adhesive , dowel material * adhesive , obturating system * dowel material * adhesive ) . Duncan 's test was used for pairwise comparison . The significance level was set at p≤ 0.05 . Statistical analysis was performed with SPSS 16.0 . RESULTS The mean resistance to fracture ( 617.4 N ) was statistically significantly higher in the ceramic dowel with gutta-percha and Variolink ( GP/C/V ) group than in the other groups . The RealSeal and RelyX fiber dowel  group 's mean resistance was the lowest and was significantly lower than the other groups . CONCLUSIONS In this study , three factors played a part in enhancing the resistance to fracture of endodontically treated teeth . High resistance to fracture was achieved when ceramic dowels were luted with total-etch technique in gutta-percha-obturated teeth
Although the majority of the studies reported that the use of root canal sealers increased the fracture resistance of endodontically treated teeth , conflicting evidence was found for the reinforcing effect of resin , glass ionomer , and calcium silicate-based sealers while there was moderate evidence for zinc oxide eugenol-based sealers in favor of no reinforcing effect .
Conclusion On the basis of available evidence , the use of root canal sealer increases the fracture resistance of endodontically treated teeth .
Regarding the comparisons among the sealers , no conclusions could be drawn for the superiority of one sealer type to another .
Objective The purpose of this study was to systematic ally review and critically analyze the published data of in vitro studies testing the effect of root canal sealers on the fracture resistance of endodontically treated teeth .