基于锥形束CT的下牙槽神经前袢测量分析OACSTPCD

Objective To reduce the risk of implantation in the mental foramen by measuring and analyzing the anterior loop of the inferior alveolar nerve(AL)based on cone beam CT(CBCT).Methods Totally 415 patients with clinical and imaging data were selected and retrospectively analyzed,who were scheduled for implant surgery in the Department of Prosthodontics and Implantology,Affiliated Stomatological Hospital of Guizhou Medical University from November 2015 to April 2016.The AL was measured and analyzed by CBCT.They were classified according to gender,age(20-＜45 years old group,45-＜60 years old group,60-75 years old group)and mandibular premolars dentition status(mandibu-lar premolars dentate group,mandibular premolars edentulous group),the differences in prevalence of anterior loop and the length of the anterior loop for each patient were analyzed among different groups.Results AL was present in 338 of 415 patients,with an prevalence rate of 81.4％.The AL length was 0.25-5.40 mm,with a mean length of(2.07±0.95)mm.AL length on the left mandible[(2.24±1.10)mm]was greater than that on the right[(1.98±1.08)mm],and the difference was statistically significant(t=3.040,P=0.002).The prevalence rate of AL in mandibu-lar premolars dentate group(83.8％)was significant-ly higher than that in mandibular premolars edentu-lous group(59.0％).The incidence of AL in 20-＜45 years old group,45-＜60 years old group and 60-75 years old group was 86.3％,78.6％and 52.5％,respectively,and the differences were statistically significant(P＜0.05).However,there were no statistically sig-nificant differences in the prevalence and length of AL between patients with different gender,or in AL length among dif-ferent age groups and between mandibular premolars dentate group and mandibular premolars edentulous group(P＞0.05).Conclusion The prevalence rate of AL is high and the average range of AL length exhibits a wide variation.Pa-tients with mandibular premolars dentate and younger patients may have higer risk for clinical implant in the mental fora-men.Using CBCT scans to detect the AL and its length is of great significance in reducing the potential complications of implant surgery in the mental foramen.