REP Barrier Material — ORE Part 1 MCQ

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ModerateEndodonticsREP Barrier MaterialORE Part 1

During regenerative endodontic treatment of an immature permanent tooth with pulp necrosis, apical bleeding is induced and a blood clot forms within the canal. Which material is placed over this clot as the coronal barrier before the definitive restoration?

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Reveal the answer and explanation

Correct answer: A — Mineral trioxide aggregate or Biodentine

Explanation lettering: D = shown as C · C = shown as D

A is correct. In regenerative endodontic procedures, apical bleeding creates an intracanal blood clot that acts as a scaffold. A well-sealing hydraulic calcium-silicate barrier is then placed over the clot before the tooth is restored. MTA is the conventional barrier material, and Biodentine is an accepted alternative. Gutta-percha and sealer are used for conventional canal obturation and would occupy the canal rather than preserve the regenerative scaffold. Calcium hydroxide and antibiotic paste may be used as interim intracanal medicaments for disinfection, not as the definitive coronal barrier. Zinc oxide-eugenol, zinc phosphate, formocresol and ferric sulphate do not provide the contemporary bioactive barrier required in REP.

Reference: Rosa WL, et al. Regenerative Endodontic Procedures Using Contemporary Endodontic Materials. Materials (Basel). 2019. https://pubmed.ncbi.nlm.nih.gov/30893790/