Fig. 1

Pre Operative X ray

Tooth #37 with irreversible pulpits.

Root canal morphology showing fused roots and the looks of a 2 rooted and most probably 2 canals system.

Fig. 2

X-rays Post Op showing 2 canals obdurated with abrupt apical curvatures! 

Mesial canal showing partial anastomosis looking obturation in coronal third of mesial root

Core build up done above obturation

Patient is still tender to percussion few weeks post treatment.

CBCT imaging was taken to assess the obturation done and explore the root canal morphology for any hidden untreated anatomy.

Axial aspect showing missed Buccal root canal.

Fig. 3

Multiple section of axial view CBCT Lower Left second molar showing morphology of missed buccal canal

Access cavity refinement and MB canal location detected with ultrasonic tips under magnification.

Root canal was scouted with K file #08 with the use of a file holder for better visibility and access in LL7 area 

Fig. 4

PerOP Xray showing File #08 in place very intwined with ML canal

Shaping stage using heat treated reciprocating mechanical files .

Fig. 5

X-ray of Cone fit in place prior obturation

Drying and obturation using Warm Vertical Compaction

Core Build up using Flowable Bulk Composite under Rubber Dam Isolation

Fig. 6

Post Operative Xray with obturation of the missed canal with new core build up

Conclusions

The total number of roots, root canals, root canal anatomical configurations of lower second molar has been demonstrated by multiple studies to have a racial predisposition. (Plotino 2013, Silva 2013, Kim 2015 & Pawar 2017). For example, the most common morphology for Indians was the presence of 2 separate roots located mesiodistally (79.35%). It also was demonstrated that there is a higher incidence of C-shaped canals with fused roots compared to the Chinese or Korean population. 

A careful anatomical diagnosis should be always done to avoid missing part of the anatomy. Missed canal like in this clinical case is one of the main reasons for primary treatment failure and the development of apical lesions (Witherspoon 2013, Baruwa  2020) 

In conclusion, three-dimensional imaging allows the observations of exact shape, number and location of roots canals. The use of CBCT enables accurate assessment of the canal anatomy, thereby making endodontic diagnosis and treatment planning more predictable. 

Bibliography

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