Tooth 20 was referred for endodontic retreatment. Patient has increased discomfort chewing and also spontaneous pain. Dx: Acute apical periodontitis with atleast 2 root canals untreated.
End of visit 1, all canals were cleaned and shaped to length. 2 buccal canals (MB,ML) and 1 Lingual canal were identified and treated. MB canal was the hardest of all to treat as the original treatment has ledged the canal space making negotiating to length difficult.
2nd visit – 
The canals were obturated and I placed cavit /IRM as interim restoration. patient is returning for retreat in 19 and the final restoration wll be done at that time.
Relevant Facts: Up to 40% of lower bicuspids have more than 1 canal. Even more so in black populations. Only 5% of all lower bicuspids have 3 canals and that is the highest number reported in the literature. These cases are fun to treat if one uses magnification and special microendodontic instruments. Otherwise its very stressful to treat these teeth. When 3 canals exist more often than not there are 2 canals to the buccal and 1 to the lingual.
Occasionally they could lie in a Letter \’C\” shape. its important to recognise the anatomy from straight and angled radiographs. case selection is key in these cases if you want to avoid misadventures.
Hope you find this case interesting.
