Do TT, Truong NK, Bien TBN, Nguyen AK, Nguyen QT. ANATOMICAL CHARACTERISTICS OF ROOTS, MORPHOLOGY OF ACCESSORY ROOT CANAL SYSTEM AND ISTHMUS OF VIETNAMESE MANDIBULAR FIRST MOLARS. CTJUMP. 2023;(63):201-210. doi:10.58490/ctump.2023i63.1505