Start practicing

Endodontics · single question

Which tooth has the most likely accessory/additional canals?

  1. Tooth #2 (maxillary second molar)
  2. Tooth #14 (maxillary first molar — mesiobuccal root)
  3. Tooth #20 (mandibular second premolar)
  4. Tooth #6 (maxillary canine)
Show answer and explanation

Correct answer: B. Tooth #14 (maxillary first molar — mesiobuccal root)

  • A. Maxillary second molars can also have an MB2 but at lower rates than maxillary first molars.
  • B. Correct. The mesiobuccal (MB) root of maxillary first and second molars (#14, #3) has a very high prevalence of a second canal (MB2) — reported in 50–95% of cases. This is a critical clinical and exam concept.
  • C. Mandibular second premolars (#20, #29) most commonly have a single canal (C-shaped or complex configurations occur in ~25%).
  • D. Maxillary canines (#6, #11) almost always have a single canal.

Practice Endodontics questions Endodontics study notes

More Endodontics practice questions