Figure 1

Classification of root canal configuration. Type I; a single canal extends from the pulp chamber to the apex. Type II; two separate canals leave the pulp chamber and join short of the apex to form one canal. Type III; one canal leaves the pulp chamber, divides into two within the root, and then merges to exit as one canal. Type IV; two separate and distinct canals extend from the pulp chamber to the apex. Type V; one canal leaves the pulp chamber and divides short of the apex into two separate and distinct canals with separate apical foramina. Type VI; two separate canals leave the pulp chamber, merge in the body of the root, and re-divide short of the apex to exit as two distinct canals. Type VII; one canal leaves the pulp chamber, divides and then rejoins within the body of the root, and finally re-divides into two distinct canals short of the apex. Type VIII; three separate and distinct canals extend from the pulp chamber to the apex.