Cone-beam computed tomography investigation of middle mesial canals and isthmuses in mandibular first molars in a Chinese population

Table 1 Prevalence of MM and isthmus

	Isthmus	MM	Without communication	Total
Number	198	11	148	357
Prevalence	55.5%	3.1%	41.4%	100%

ISSN: 1472-6831