Root canal morphology of primary molars - A cone beam computed tomography (CBCT) study

To evaluate the root and canal morphology of primary maxillary and mandibular molars in an Indian population using cone-beam computed tomography (CBCT).

A retrospective cross-sectional study was performed, where CBCT scans of children less than 10 years of age taken for valid diagnostic purposes previously were considered and images were analyzed. The number of roots, root canals, and variations in morphology were recorded. Left-right symmetry was also noted.

A total of 433 deciduous maxillary and mandibular primary molars were studied. It was observed that two separate roots with three separate canals were common in primary mandibular first molars, whereas two separate roots with two canals in each root were common in mandibular second primary molars. In primary maxillary molars, three separate roots with one canal each were the most common. Maxillary first molars (17.21%) and 17.35% second molars had fused distobuccal and palatal roots. It was observed that primary maxillary molars showed more left-right symmetry (86.7% in first molars and 82.7% in second molars) compared to primary mandibular molars (54.05% in first molars and 68% in second molars).

It was concluded that in both primary maxillary first and second molars, three separate roots, a mesiobuccal root, a distobuccal root, and a palatal root with one canal in each root, were the most common. Two separate roots with three separate canals were the most common in primary mandibular first molars, whereas two separate roots with two canals each in both roots were more common in mandibular second primary molars.