牙根纵裂导致牙槽骨缺损的数字化模型重建与分析

Digital model reconstruction and analysis of alveolar bone defect caused by vertical root fracture

目的:评价根尖周炎(apical periodontitis,AP)与牙根纵裂(vertical root fracture,VRF)导致的根尖周骨缺损形态的差异。方法:选取发生AP、VRF且伴有根尖周骨缺损的上下颌后牙的锥形束CT(cone-beam computed tomography,CBCT)资料,利用交互式医学图像控制系统(materialise’s interactive medical image control system,Mimics)软件进行数字化模型重建并对骨缺损区定量分析,比较两组患牙的根尖孔水平面冠方的骨缺损体积占全部骨缺损体积的百分比。结果:两组体积比值有统计学意义(P<0.05)。当体积比值趋于1时,VRF的可能性大。结论:VRF导致的根尖周骨缺损主要位于患牙根尖孔水平面的冠方。对根尖周骨缺损的定量测量有助于VRF的正确诊断。

Objective:To evaluate the difference of periapical bone defect morphology caused by apical periodontitis(AP)and vertical root fracture(VRF).Methods:Cone-beam computed tomography(CBCT)data of the maxillary and mandibular posterior teeth with AP and VRF and peripheral periapical defects were selected and reconstructed by Mimics software and quantitatively analyzed in the defect area.The percentage of bone defect volume above the level of the apical foramen of the two groups was calculated as the volume of the total bone defect.Results:The volume ratio between the two groups was statistically significant(P<0.05).When the volume ratio tends to 1,the possibility of vertical root fracture is great.Conclusion:VRF-induced periapical bone defect is mainly located above the level of the apical foramen of the tooth.Quantitative measurement of the periapical bone defect contributes to the diagnosis of VRF.