Evaluating the maxillary premolar with three canals or endodontic therapy.

By Belizzi R, Hartwell G

Date: 06/1981
Journal: Journal of Endodontic


•Purpose: to describe the morphology of three rooted maxillary premolar and its radiographic features..


•Not mentioned.

•n: 325 1st  premolars  (3.7% with three canals) and 398 2nd  premolars  (0.3% with three canals ) 

• Inclusion criteria; exclusion criteria: not mentioned. •Highlights: •Categories:

•1- Category 1: fusion of all three roots or only the two buccal ones, and a semi-fused or free palatal root.

Its the most difficult category to be radiographically assessed.

•2- Category 2: normal separation of the buccal roots at the level mid-root or apical third, with either a semi fused or free palatal root.

•3- Category 3: normal separation of the buccal roots up to the cervical level, with a free palatal root and a classic tripod appearance.

•Clinical significance:

•A chamber that is not aligned to the usual B-P plane; triangular shaped; too large in M-D direction; eccentric location of orifice (not always) should be scrutinized for a third canal maxillary premolars.