ABE Regenerative Endodontics

Question 1

Which of the following is the PRIMARY goal of regenerative endodontic procedures (REPs) in immature permanent teeth with necrotic pulps?

Accepted Answer

Continued root development and thickening of dentinal walls

Answer

The primary goal of REPs is to allow continued root development (increased root length and wall thickness) in immature teeth, ideally restoring a functional pulp-dentin complex.

Question 2

According to the AAE clinical considerations for REPs, which irrigant should be used CAUTIOUSLY or avoided at full concentration in immature teeth because it can damage Hertwig's epithelial root sheath and stem cells?

Accepted Answer

Sodium hypochlorite at concentrations above 1.5%

Answer

Sodium hypochlorite at concentrations greater than 1.5% can be cytotoxic to stem cells of the apical papilla (SCAP) and Hertwig's epithelial root sheath, so concentrations ≤1.5% are recommended.

Question 3

What is the significance of EDTA in the final irrigation step of a regenerative endodontic procedure?

Accepted Answer

It releases growth factors from dentin and promotes stem cell differentiation

Answer

EDTA demineralizes the dentin surface and releases bioactive molecules such as TGF-β, FGF, and BMP, which promote stem cell attachment, proliferation, and differentiation.

Question 4

Triple antibiotic paste (TAP) used in regenerative endodontics is classically composed of which three antibiotics?

Accepted Answer

Metronidazole, ciprofloxacin, and minocycline

Answer

The classic TAP formulation consists of metronidazole, ciprofloxacin, and minocycline, first described by Hoshino et al. to disinfect infected root canals.

Question 5

Which intracanal medicament for REPs is preferred over triple antibiotic paste when tooth discoloration is a primary concern?

Accepted Answer

Double antibiotic paste (metronidazole + ciprofloxacin)

Answer

Double antibiotic paste (metronidazole + ciprofloxacin, without minocycline) eliminates the tetracycline-class drug responsible for intrinsic crown discoloration while retaining broad-spectrum antibacterial activity.

(ABE) American Board of Endodontics Practice Test

(ABE) American Board of Endodontics Practice Test

ABE Regenerative Endodontics