CBCT Imaging Study Of The Structure, Location And Branches Of The Mandibular Nerve Canal

Objective:To study the structure,position and bifid of the mandibular canal by CBCT image.To observe the morphology of the bifurcated mandibular canal(BMC)and its incidence in Chinese population by cone beam CT(CBCT)imaging technique,so as to provide reference data for oral surgery and reduce the damage to.Methods:A retrospective study was conducted on 810 CBCT images from May 2017 to February 2018.The incidence and distribution of BMC,the type of BMC,the relationship between the mandibular canal and the position of mandibular molar were observed by SmartV2 software.CBCT data of 160 people were collected,The relationship between mandibular canal and mandibular molar was observed,and the position of anterior loop was observed.Results:Among 810 patients,205 patients were found to have bifurcated mandibular canals(25.31%).Among 409 male patients,98 patients had bifurcated mandibular canals and 107 female patients had bifurcated mandibular canals(47.80%and 52.20%respectively).There was no significant difference in the distribution of bifurcated mandibular canals between men and women(P>0.0).There were 322 bifurcated mandibular canals in 205 patients,117 bilateral mandibular canals occurred simultaneously,88 unilateral bifurcated mandibular canals occurred unilaterally,and the bifurcated mandibular canals were divided into four types according to their orientation:type III(anterior mandibular canal)bifurcated mandibular canals were the most common,totaling 117,accounting for 3.Type I(posterior mandibular canal)was 77(23.91%),type IV(buccal-lingual-mandibular canal)was 76(23.60%)and type II(submandibular canal)was 52(16.15%).The average diameters of bifurcated mandibular canal brancheswere 1.51 mm,respectively.There was no significant difference in the diameters of each type of bifurcated mandibular canal branches.The average length of the bifurcated mandibular canal branches was 10.00 mm(6.07-13.23 mm);62.42%of the bifurcated mandibular canals were adjacent to the mandibular third molars.Conclusion:CBCT image can help to observe the structure,position and bifid of the mandibular canal.It can provide reference data for treatment plan,and avoid or reduce the nerve damage in treatment.