Cone Beam CT Observation Of Bifid Mandibular Canal In Adults In Shanxi Province

Objective:To observe the morphology and distribution of mandibular canal branches in adults in Shanxi area by cone beam CT,and to study the relationship between gender,left and right sides and the incidence of mandibular canal branches in different age groups,so as to provide guidance and basis for clinical practice of extraction,implantation and bone extraction in mandibular posterior teeth area,and reduce the occurrence of surgical complications such as bleeding and nerve injury.Methods:CBCT scanning data of 400 cases of Han nationality in Shanxi Province of China were collected from the Department of Stomatology and radiology,the first hospital of Shanxi Medical University from November 2018 to November 2019.NNT viewer software was used to observe the occurrence of bifid mandibular canal.The length,diameter,angle of bifid mandibular canal and the distance between bifid mandibular canal and buccal bone plate were measured.Statistical methods were used to analyze the relationship between gender,left and right sides,age and the incidence of mandibular canal branches.Results:The incidence of bifid mandibular canal in 400 patients was 40.75%(163 / 400),which occurred in 248 mandibles(31.0%).In the classification of bifid mandibular canal,45.97%,23.39%,28.63% and 2.02% of the bifid mandibular canal were retromolar canal,dental canal,forward canal and buccolingual canal,respectively.The average diameter and length of bifid mandibular canal were(1.18 ±0.36)mm and(12.58 ± 4.72)mm,respectively.The average angle between the bifid mandibular canal and the main mandibular canal was 42.46°±18.14°and the average distance between the retromolar canal and buccal bone plate was(6.04±1.25)mm.Conclusions:CBCT is the best imaging method to measure bifid mandibular canal at present.This study found that the incidence of bifid mandibular canal in Shanxi adults is 40.75%,and the retromolar canal is the most common type;there are some individual differences in the length,diameter and angle of bifid mandibular canal.The thickness of bone extraction in the lateral oblique area of mandible should not be more than 5mm.The incidence of bifid mandibular canal is high in adults in Shanxi area,especially in the retromolar area.CBCT should be taken to estimate the risk before surgical operation,so as to avoid serious complications caused by intraoperative injury.