Fig. 1

65 year old woman

Complaining about pain while chewing in left mandible

On clinical examination big composite restoration was detected

Pain on precision and positive bite test.

No signs of crack or fracture

Probing dept of no more then 3 mm

x ray examination showed previously insufficient root canal treatment

Pulpal diagnosis : Previously treated 36

Periapical diagnosis:Symptomatic apical periodontitis

Fig. 2

After cleaning the pulp chamber from old filing material access to the root canal system was established.

It was obvious that the canal anatomy is challengin.

One oval mesial canal and one c shaped distal obturated with some gutta percha cones. The removal of gutta percha was easy .

TIP: Always try to remove the gutta percha mechanically from the canal: solvents make the gutta percha sticky and really is a challenge to remove completely the dissolved gutta from the canal walls

The shaping was done with CM files.

TIP: Irregular canal systems like oval canals and C shaped canals are impossible to be cleaned and shaped without brushing movements.The brushing movements have to be done away from the furcation.

Fig. 3

The most crucial moment in such cases is the irrigation and activation of the irrigants. In this case I have used 5% Natrium Hypochlorite Sonically activated. Also I used EDTA 17% for dentin conditioning and better Hypochlorite penetration into dentin tubules.

Fig. 4

The obturation was made with epoxy sealer and Squirt technique

Only warm gutta percha can fill all the gaps and adapt to the walls of this kind of irregular canal system anatomy.

TIP :Push the needle in the  previously “painted” with sealer canal until it gets in contact with canal walls but avoid it to be wedged into the dentine. Start extruding warm gutta percha and wait for the needle to be pushed out of the canal from the back pressure of the gutta percha.

This tooth was finished with SDR composite over the orificiums then fiber reinforced composite and then nano composite on the top. Crown was advised.

TIP: Always cover the Short fiber reinforced composite with regular composite because of a possibility of microleakage in between the fibers.

Fig. 5

post op

Fig. 6

Different shift

Fig. 7

6 months recall


The right diagnosis and the right technique of mechanical and chemical treatment as well as the right technique of obturation can lead us to a successful treatment of such irregular anatomies of the root canal system


Raisingani D, Gupta S, Mital P, Khullar P. Anatomic and Diagnostic Challenges of C-Shaped Root Canal System. Int J Clin Pediatr Dent 2014;7(1):35-39.

Jesús Alejandro Quiñones Pedraza (September 6th 2019). The C-Shaped Root Canal, Human Teeth. Key Skills and Clinical Illustrations, Zühre Akarslan and Farid Bourzgui, IntechOpen