C-shaped root canal configuration: A review of literature

By Fernandes M, de Ataide I, Wagle R

Date: 04/2014
Journal: J Conserv Dent.


•Purpose:  to review and discuss the etiology, incidence, anatomic features, classification, diagnosis and

management of the C­-shaped canal configuration.

•Materials &Method:

Manual and electronic searches of literature were performed from 1979 to 2012¬ in Pub Med by crossing the keywords: C­shaped canals¬ mandibular second molar¬ mandibular first premolar¬ root canal morphology.

•Most highlighted Results:

•First Described by Cooke and Cox .

Etiology:  The failure of fusion of Hertwig’s epithelial sheath. (genetic origin)

Incidence: higher in Asian population and in mandibular 2nd molar. •Anatomic features: 

Roots: conical or square configuration – Fusion labially or lingually of the mesial and distal roots- Occluso-apical groove on the buccal or lingual surface.

Pulp chamber: Low bifurcation and connecting slit.

Root canal system: C-shaped canals shows broad, fan-shaped communications from the coronal to the apical third of the canal. Accessory and lateral canals, inter-canal and apical delta can be found in (11-41%), in the apical region of C-shaped canals.


Numerous classification (Figure 1), earliest by Manning and Melton et al. (only the appearance of the canal orifices.


-RG characteristics: Radicular fusion- radicular proximity- a large distal canal or a blurred image of a third canal in between.

-Pre clinically: A longitudinal groove on lingual or buccal surface may predispose the tooth to localized perio disease (first indication).

-Access: Fan et al, features: Fused roots, a longitudinal groove, at least 1 cross-section of the canal belong to the C1, C2, or C3 configuration. (figure 2)

Management: Careful location and negotiation of the canals and the meticulous mechanical and chemical debridement of the pulp tissue should be carried out in order to successfully treat a C-shaped canal.

•Clinical significance:

Knowledge of the C-shaped canal configuration is essential to achieve success in endodontic therapy.