Fig. 1

Classification of C shaped canals

Fig. 2

Case 1

C1, Type 1


A- Access Cavity 

B- Cone fitting

C- Final Obturation Resembles C- Shape  

Fig. 3

Down packing and back filling

Fig. 4

Notice apical delta after obturation

Fig. 5


C2 , Type III

Access Cavity & Pre-OP Xray 

Fig. 6

Working length determination

Fig. 7

A- Injecting BC Sealer 

B- Cone Fitting

Fig. 8

Cone fitting and clinical X-ray

Fig. 9

Down packing

Fig. 10

Final obturation and X-ray


Fig. 11


C3 , Type I

Access Cavity “ with 3 main canal orifices & we can see the isthmus between them clearly “

Fig. 12

Down packing

Fig. 13

Final obturation

Fig. 14


C3, Type I

Access Cavity 

Fig. 15

Down packing

Fig. 16

Final obturation

Fig. 17



A- Pre-OP Xray

B- Cone Fitting 

C- Down-Packing

D- Obturation 

E- Negative 


- The C-shaped root canal configuration has an ethnic predilection and a high prevalence rate in mandibular second molars.

-The C-shaped anatomy represents an important and challenging anatomical variation during negotiation, debridement and obturation, Understanding the anatomical presentations of this variation will enable the clinician to manage these cases effectively.


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