下颌神经管分支发生、分布情况及意义

摘要

目的：观察下颌神经管分支的发生及分布情况，为种植外科和牙槽外科手术提供参考依据。方法选择进行锥形束计算机X线体层摄影（CBCT）检查者200例，分析其CBCT影像，统计在全下颌样本、单侧下颌样本、右侧下颌样本及左侧下颌样本中分支管发生率，在单侧下颌样本、右侧下颌样本及左侧下颌样本中磨牙后区、第二磨牙区、第一磨牙区及前磨牙区分支管发生率，单侧下颌样本、右侧下颌样本及左侧下颌样本中Naitoh′s分类法各类型分支管数量占样本分支管总数的构成比。结果共发现730支下颌神经管分支，全下颌样本分支管发生率为98．50％，单侧下颌样本为89．75％；右侧下颌样本为93．50％、左侧下颌样为86．00％（172／200），两侧分支管发生率比较P＜0．05。单侧、右侧及左侧下颌样本中磨牙后区、第二磨牙区、第一磨牙区及前磨牙区神经管分支管发生率均逐渐降低（ P均＜0．05）。 Naitoh′s分类法中Forward类、Dental类、Buccolingual 类、Retromolar类分支管构成比分别为70．96％、7．67％、6．16％、5．07％，74支（10．14％）分支管不能纳入Naitoh′s分类法。结论下颌神经管分支普遍存在，右侧和左侧下颌神经管分支发生率可能存在差异，下颌神经管行进过程中分支管发生率逐渐降低，下颌神经管分支最常在主管上方分出。%Objective To observe the prevalence and distribution of mandibular canal branches and to provide the ref -erence for implant surgery and alveolar surgery .Methods Totally 200 patients who received cone-beam computed tomo-graphy (CBCT) examination were selected in the study .The mandibular canal branches were observed by CBCT and we re-corded the region and number of mandibular canal branches .The insidences were calculated and the branches were classified according to Naitoh′s classification , the proportion of each type were calculated .Results The total number of mandibular canal branches was 730.The incidence of total mandibular canal branches was 98.50%, and that of unilateral mandibular ca-nal branches was 89.75%.The incidence of mandibular canal branches was 93.50%in right mandible samples and 86.00%in left mandible samples, respectively, which indicated statistically significant difference (P<0.05).The prevalence of mandibular canal branches in retromolar region , second molar region , first molar region and premolar region of unilateral , right and left mandibular specimens was gradually decreased , statistically significant differences were found in the prevalence of branches among different regions (all P<0.05).According to Naitoh′s classification, the proportion of Forward type, Dental type, Buccolingual type, Retromolar type (branches above mandibular canal ) in this study was 70.96%, 7.67%, 6.16%, and 5.07% of the total number of mandibular canal branches in unilateral mandible samples , and 74 branches (10.14%) couldn′t be classified.Conclusions The mandibular canal branches are abundant .The difference in the preva-lence may exist between the right and left mandibular canal branches .The prevalence of mandibular canal branches decreases gradually from posterior to anterior region .Forward type is the most frequent in Naitoh′s classification .