The impact of postoperative intracoronal bleaching on the microtensile bond strength at the composite-dentin interface


Ayan G., Misilli T., Buldur M., DOĞAN A. N.

Dental materials journal, vol.44, no.5, pp.589-598, 2025 (SCI-Expanded, Scopus)

  • Publication Type: Article / Article
  • Volume: 44 Issue: 5
  • Publication Date: 2025
  • Doi Number: 10.4012/dmj.2025-046
  • Journal Name: Dental materials journal
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Biotechnology Research Abstracts, Communication Abstracts, Compendex, EMBASE, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.589-598
  • Keywords: Adhesion, Intracoronal bleaching, Microtensile bond strength, Nanoleakage
  • Erciyes University Affiliated: Yes

Abstract

The study evaluated the effects of postoperative bleaching with HP and CP on microtensile bond strength (μTBS) and nanoleakage of composite restorations using total-/self-etch protocols. Sixty incisors with Black V cavities were restored using a multimode adhesive in total-/self-etch mode and resin composite. Samples were divided into five groups: control, CP×2, CP×5, HP×2, HP×5. After bleaching, 1×1×8 mm composite blocks (n=10) were tested for μTBS, and failure types were assessed. Two samples per group were analyzed for nanoleakage via scanning electron microscope (SEM). Two-way analysis of variance, Bonferroni correction, and stepwise linear regression were applied. CP×5 and HP×5 groups exhibited significantly reduced μTBS compared to control, and the self-etch protocol resulted in lower values regardless of bleaching method. Regression analysis confirmed significant effects of adhesive (total-etch) and bleaching (CP×5, HP×5). A significant relationship was found between failure modes and bleaching methods for each adhesive protocol, with adhesive failures being the most frequent. SEM revealed nanoleakage in all groups.