Clinical study of root canal numbers in maxillary second primary molars

To investigate the root canal numbers of maxillary second primary molars.

216 maxillary second primary molars from 204 children aged 3-8 years old were selected. All the teeth need to do the root canal therapy. After opening the pulp chamber, the root canal were examined and determined with small size K file and 17% ethylene diaminetetraacetic acid (EDTA). Hand instruments were used for root canal preparation and then zinc-oxide iodoform paste was used for filling.

216 maxillary second primary molars, 122 teeth had three root canals (56.5%), and 94 teeth had four root canals (43.5%). The incidence of second mesiobuccal canal (MB2) was 41.2%. There was no correlation between the incidence of the MB2 canal and gender and tooth position.

The root canals of maxillary second primary molars had more variations, and there was a high incidence of the second mesiobuccal canal.