Most mandibular first premolars (two teeth in front of your lower molars) have a single root and a single (nerve) canal, 24% have greater than 2 canals. Typically, people from the African-American, Turkish and Chinese populations have an increased incidence of multiple canals.
Source: Cleghorn BM et al, The root and root canal morphology of the human mandibular first premolar: a literature review, J Endod 2007, Vol 33, pg 509-516.
Hans Skariah, B.Sc., DMD
Promenade Court Dental Health Group in Mississauga
2233 Hurontario St., Mississauga, ON, Canada
(1/2 km north of the QEW in the Dome Building)