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 final irrigation protocols on microhardness reduction and erosion of root canal dentin.
This study aim ed to evaluate the effect of final irrigation protocol s on microhardness reduction and erosion of root canal dentin .  Sixty root canals from m and ibular incisors were instrumented and r and omly divided into six groups ( n = 10 ) according to the irrigant used : QMiX , 17 % EDTA , 10 % citric acid ( CA ) , 1 % peracetic acid ( PA ) , 2.5 % NaOCl ( solution control ) , and distilled water ( negative control ) . The chelating solutions were used to irrigate the canal followed by 2.5 % NaOCl as a final flush . After the irrigation protocol s , all specimens were rinsed with 10 mL of distilled water to remove any residue of the chemical solutions . Before and after the final irrigation protocol s , dentin microhardness was measured with a Knoop indenter . Three indentations were made at 100 µm and 500 µm from the root canal lumen . Afterwards , the specimens were prepared for scanning electron microscopic analysis and the amount of dentin erosion was examined . Wilcoxon and Kruskal-Wallis tests were used to analyze the results with a significance level set at 5 % . At 100 µm , all protocol s significantly reduced dentin microhardness ( p < .05 ) , while at 500 µm , this effect was detected only in the EDTA and QMiX groups ( p < .05 ) . CA was the irrigant that caused more extensive erosion in dentinal tubules , followed by PA and EDTA . QMiX opened dentinal tubules , but did not cause dentin erosion . Results suggest that QMiX and 17 % EDTA reduced dentin microhardness at a greater depth . Additionally , QMiX did not cause dentin erosion
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 .