The Application Of CBCT In Sex And Age Determination In Forensic Medicine

Objective:Individual age and sex determination are very important in forensic medicine.This study use 3D image of the maxillary canines acquired by CBCT and analyse the information to explore the value of CBCT in sex and age determination in forensic medicine,in order to establish a new method for individual identification.Method:380 cases of CBCT image which were taked during September 2015 to August 2015 in shanxi medical university stomatological hospital were collected.Mimics17.0 was used to measure pulp volume and tooth volume of maxillary canines to calculate pulp/tooth volume ratio.Finally,103 cases were collected which can be measured accurately.All data were used SPSS16.0 statistical analysis software to establishing a database.Fisher discriminant method and Linear regression analysis were carried out to establish a new method for sex and age determination.Result:Using Fisher discriminant method for sex determination,teeth volume combine with PV/TV show higher Coincidence rate.The discriminant equation is Y=0.009(TV)+28.896(PV/TV)-6.962.Cross-validated discriminant method shows the total discriminant coincidence rate is 60.8% for 51 cases of men and 76.9% for 52 cases of women.The regression analysis for age determination is Y=69.137-621.200(PV/TV),P<0.001,R = 0.544 when we use PV/TV.The equation is Y=47.66 + 0.032(TV)-0.946(PV),P<0.001,R=0.517 when we use pulp volume and teeth volume to calculate age.Conclusion:1.When use the teeth volume combine with PV/TV as a research indicator for sex determination,the experiment is simple and can narrow the scope of the individual identification.This study can be used for forensic clinical work after further improvement.2.The PV/TV can be used for age determination.3.The pulp volume combine with teeth volume are meaningful for age determination.Legal medical expert can use 3D method for age determination in special circumstances as a assist method in clinical work.4.CBCT can be used for age and sex determination at the same time to get more information in legal medical expert’s clinical work.Finally,the efficiency of clinical work is improved.