The effect of intraorifice barriers (TheraCal LC, Lime-Lite and Ionoseal) on the fracture resistance and failure patterns of endodontically treated teeth submitted to intracoronal bleaching

BACKGROUND: The aim of the study was to compare the root reinforcement potential of different light cured intraorifice barriers (TheraCal, lime-lite, Ionoseal and resin-modified glass-ionomer [RMGI] [Fuji II LC]) with or without bonding agent placed in the orifice of endodontically treated and bleached teeth. MATERIALS AND METHODS: In this experimental in vitro study, single-rooted bovine teeth were instrumented and obturated with gutta-percha. Except the control group, in other specimens, gutta-percha was removed 3 mm under cementoenamel junction. Then, the specimens were divided into seven groups according to the bases was applied: TheraCal LC, TheraCal LC with bonding agent, Lime-Lite, Lime-Lite with bonding agent, Ionoseal, Ionoseal with bonding agent, and RMGI (Fuji II LC). After internal bleaching, the teeth were decoronated. Then, all the groups were subjected to fracture resistance testing using Universal Testing Machine. For evaluating fracture resistance, analysis of variance and Tukey's test were used and for comparing the mode of fracture fisher test was applied in SPSS software. The significance was determined at (α = 0.05) confidence interval. RESULTS: The group of TheraCal LC with bonding agent showed better fracture resistance as compared to the control group (P = 0.004). Although there was no statistically significant difference in the pairwise comparison between the other groups. CONCLUSION: TheraCal LC with bonding agent can be used as intraorifice barriers with good fracture resistance in endodontically treated and bleached teeth.