Determine the relationship of age, gender, and race to the frequency of second canals in mesiobuccal root (MBR) of maxillary first molars.
•Recorded data were collected of treated maxillary 1st molar by one expert clinician.
•Race was categorized as: white, black, or other MBR was determined to have 2 canals and 2 separate foramina by specific criteria illustrated in Table.1.
•Data analysis was conducted according to a priori planned design •Pearson’s correlation r was used to determine the direction and strength of the linear relationship between no. of canals with the no. of foramina and the total no. of canals in maxillary 1st molars
•Direct relationship between no. of canals in MBR and no. of foramina; if 1 canal exist it will have one foramen in 18%; 2 canals will have 16.7% for a one foramina and 60% for 2 foramina
•Direct relationship between no. of total canals and no. of MBR canals; if there are 4 canals the MBR will have 2 canals in 75%
•Before age 20 and after age 40, there were fewer canals; which were clinically discernible in Fig. 6.
•There is a low inverse relationship between the number of foramina and age
•Race, sex, or tooth position do not impact the number of canals or foramina in the MBR.
•Knowledge of root canal frequency in each tooth assist in adequate RCT. A Heart shaped access cavity will aid in locating the minor canal in MBR as illustrated in Fig.9.