AGD Endodontics and Pulpal Therapy 5

Question 1

Which microorganism is most commonly associated with persistent endodontic infections and is resistant to standard irrigation protocols?

Accepted Answer

Enterococcus faecalis

Answer

Enterococcus faecalis is highly resistant to calcium hydroxide and commonly colonizes filled canals, making it the leading cause of treatment failure.

Question 2

During root canal treatment, a separated instrument is found in the middle third of a curved canal. What is the FIRST recommended action?

Accepted Answer

Assess retrievability with magnification and consider bypass before removal attempts

Answer

The recommended initial approach is to assess the fragment's position and retrievability under magnification, then attempt bypass if removal carries high risk.

Question 3

What is the purpose of placing calcium hydroxide as an inter-appointment medicament?

Accepted Answer

Provide antimicrobial action and stimulate periapical healing

Answer

Calcium hydroxide raises intracanal pH to ~12, killing residual bacteria and promoting periapical tissue repair between appointments.

Question 4

A mandibular second premolar is known for its challenging anatomy. What variant most commonly causes missed canals?

Accepted Answer

Two canals that merge into one (Type II Vertucci)

Answer

Mandibular second premolars frequently have two canals (Vertucci Type II) that join apically, with the second canal easily missed if access is inadequate.

Question 5

The 'apical vapor lock' phenomenon during irrigation refers to:

Accepted Answer

Trapped air at the apex preventing irrigant from reaching the last few millimeters

Answer

Air trapped apically creates a vapor lock that blocks irrigant penetration; this can be countered with sonic/ultrasonic agitation or negative pressure techniques.

(AGD) Academy of General Dentistry Certification Practice Test

(AGD) Academy of General Dentistry Certification Practice Test

AGD Endodontics and Pulpal Therapy 5