Comparative Evaluation of Cervical Penetration of Hydrogen Peroxide Using 35% Hydrogen Peroxide and Sodium Perborate Bleaching Agents with Different Intraorifice Barriers-An in Vitro Study

Abstract

Introduction: Tooth discoloration following trauma or endodontic treatment is commonly managed using intracoronal bleaching. However, bleaching agents can diffuse through dentinal tubules and cause external cervical resorption. Placement of an intraorifice barrier is therefore recommended to limit peroxide penetration and protect surrounding tissues.

Objectives: The present study aimed to evaluate the effectiveness of three different intraorifice barrier materials named GIC, ProRoot MT, and Biodentine against cervical penetration of commonly used bleaching.

Methods: A total of 120 extracted single-rooted permanent teeth were endodontically treated and randomly allocated to three barrier groups (GIC, MTA, Biodentine) and one control group (no barrier). Each group was further subdivided based on bleaching agent HP, SP, and HP+SP. Peroxide penetration was quantified after 7 days using a titration-based hydrogen peroxide testing kit.

Results: Data were analyzed using one-way ANOVA with Tukey’s post hoc test. All barriers significantly reduced peroxide penetration compared to controls (p < 0.05). Biodentine consistently showed lowest penetration across all bleaching agents and least with SP (HP: 0.241 ± 0.0107 ppm; SP: 0.199 ± 0.0491 ppm; HP+SP: 0.210 ± 0.0272 ppm). MTA demonstrated similar efficacy to Biodentine (p > 0.05), while GIC exhibited the highest permeability.

Conclusions: Intraorifice barriers play a critical role in reducing peroxide penetration. Among which Biodentine provided most effective sealing, followed by MTA, while GIC showed inferior performance. Biodentine combined with sodium perborate was the safest option, minimizing peroxide leakage.