Root ZX根尖定位仪诊断牙根横折的实验研究

目的研究Root ZX根尖定位仪是否能准确诊断牙根横折的存在。方法将20颗离体单根管上前牙形成牙根横折，用Root ZX根尖定位仪分别测量横折断端不分离、横折断端分离但断端内无印模材料、横折断端分离且断端内有印模材料3种情况下的根管长度，并与实际根管长度进行比较。结果在横折断端不分离、横折断端分离但断端内无印模材料2种情况下，根尖定位仪不能探测到横折位置；在横折断端分离且断端内有印模材料情况下，电测根管长度在横折冠段实际根管长度±0.5 mm范围内为100%，可探测到横折位置。结论Root ZX根尖定位仪对没有软组织长入的牙根横折无诊断价值，但对有软组织长入的牙根横折有很好的准确性。

An in vitro study of Root ZX root apex locator to diagnose horizontal root fracture

Objective To evaluate the accuracy of Root ZX root apex locator in detecting stimulated horizontal root fractures.Methods A total of 20 single-canal maxillary anterior teeth were collected.All roots were simulated horizontal root fracture.Root ZX root apex locator measured the canal length in 3 stages:Broken ends of horizontal fractures without separation;broken ends of horizontal fractures with separation,but no impression material;broken ends of horizontal fractures with separation and impression material.The lengths measured by Root ZX root apex locator were compared with actual canal length.Results To horizontal root fracture without separation or without impression material.Root ZX root apex locator couldn't detect the horizontal root fracture.To horizontal root fracture with separation and impression material,Root ZX root apex locator detected the horizontal root fracture within ±0.5 mm in 100%.Conclusion Root ZX root apex locator lacks of diagnostic value for horizontal root fractures without soft tissue ingrowth,but provides with preferable veracity for horizontal root fractures with soft tissue ingrowth.