Root form and canal anatomy of mandibular first molars in a southern Chinese population

Abstract Racial differences in dental crown morphology have long been recognised, but the diverse aspects of root form and canal anatomy of human teeth have not received the same attention. The majority of books on dental anatomy fail to supply detailed information of the features of root and root canal morphology that occur at particularly high frequency in Mongoloid populations. These features have not been systematically documented and the implications that these variations may have upon clinical endodontics have not been fully reported. In this study 100 mandibular first molars extracted from Hong Kong Chinese patients were examined visually and radiographically. For each tooth, the number of roots, root canals, and apical foramina were noted. Fifteen per cent of the mandibular first molars examined were found to be 3-rooted. Forty-five per cent of the sample displayed 2 distal canals and 28% of the teeth had 2 separate distal apical foramina. The frequency of the second distal canal is higher than the previously reported findings for non-Mongoloid groups.