This anatomical variation occurs in only 2% of cases!
In a recent case, the MB2 canal was initially overlooked. Preoperative radiographs revealed significant periapical lesions affecting the mesial, distal, and palatal roots.
While the overall obturation was satisfactory, minor coronal leakage was observed. Through enhanced magnification and meticulous cleaning of the MB canal, MB2 was successfully identified and instrumented as a branch with a separate portal of exit. Usually, once mb2 is prepared, exploring with a precurved file, within this canal, you would feel a “catch”. If a separate MB2 orifice is not located, this “catch” could likely be the missing mb2!
Obturating with bioceramic sealers is easiest, but for those using a warm-vertical obturation technique, I recommend obturating MB2 separately and severing the gutta-percha at or beyond the split with a heated instrument.
Sometimes, the most critical details in endodontics are the ones we almost miss.



