X线投照角度对判断后牙颊舌向多根管的作用

Use of angulated radiograph in clinical judgement of obturation quality of molars with multiple root canals

目的探讨 X 线投照角度在判断多根管磨牙根管充填效果时的作用。方法选取存在近颊第二根管的上颌第一磨牙87颗、下颌第一磨牙105颗,拍摄术前 X 线片,完成根管治疗,术后分别拍摄 X 线正位投照片和远中偏位投照片,判断根充效果。结果 X 线正位投照片和远中偏位投照片能显示上颌第一磨牙 MB 与 MB2的比例分别为23.0%和81.6%,显示下颌第一磨牙近中两根管的比例分别为38.1%和90.5%,X 线远中偏位投照片显示颊、舌向根管的比例大于正位投照片(P<0.005)。结论采用 X 线远中偏位投照法能更好地显示上、下颌第一磨牙颊舌向根管的充填效果。

Objective To investigate different angle projection technique for clinical judgment of obturation quality of molars with multiple root canals. Methods Eighty-seven maxillary first molars with second mesiobuceal canal （MB2） and 105 mandibular first molars were selected. The canals were instrumented by Ni-Ti rotary instruments and obturated with lateral condensation technique. To judge the obturation quality of the root canals, the radiograph was taken at a horizontal angles of 0 and 20-30 degrees from distal direction of the tooth after the treatment. Results For maxillary first molars, periapical radiographs showed 23.0% of MB2. Distally angulated radiographs showed 81.6% of MB2. For mandibular first molars, periapical radiographs showed 38. 1% of mesiobuccal and mesiolingual canals, and distally angulated radiographs showed 90. 5% of two mesial root canals. Conclusions Most buccal-lingual distributed root canals of the first molar can be shown more clearly by distally angulated radiographs.