A micro-CT analysis of the root and root canal systems of permanent mandibular second molars
ZHOU Tao
ZHAO Chang-ming
CHAI Zhi-guo
SHEN Li-juan
JIAO Kai
NIU Li-na
GU Yong-chun
TIAN Min
ZENG Guang
Abstract：AIM:To observe the anatomic features of root and root canal systems of permanent mandibular second molars.METHODS:75 extracted permanent mandibular second molars,32 with 2 roots(2R group)and 43 with one C-shaped root(CR group),from native Chinese subjects were scanned with micro-CT.3D models of the teeth were reconstructed by Mimics 10.01 software.The anatomy of the pulp chamber floor,incidence of various forms of root canals and accessory canals were determined.RESULTS:In 2R group,type 2-1 (34.4%)and 1 -1 canal sys-temss (31.3%)were common in the mesial roots,and type 1 -1 canal system (87.5%)was frequent in the distal roots.In CR group type I (30.2%)and type IV (30.2%)pulp chamber floor were common.The incidences of Mel-ton Ⅰ,Ⅱ and Ⅲcanal form were 27.9%,14.0%and 58.1%respectively.In 2R group the incidences of accessory canals of the mesial and distal roots were 65.6%and 25.0%respectively(P<0.05).The incidences of accessory ca-nals in 2R and CR groups was 75.0%and 51.2%respectively (P>0.05).CONCLUSION:The root canal system of the mesial roots in 2-rooted mandibular second molars is more complex than that of the distal roots.The degree and location of the dentin confusion at the isthmus zones determine the type of the C-shaped canals.
Keywords：permanent mandibular second molarc-shaped canalroot canal systemmicro-CT
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 469-472,480 )