Lim K C, Teo C S
Ann Acad Med Singap. 1986 Jul;15(3):320-5.
This retrospective survey highlights some of the problems faced by undergraduate students using the bisecting angle technique in endodontic radiography. The radiographs of maxillary incisors and premolars were observed to suffer from a greater amount of distortion than radiographs of the corresponding mandibular teeth. Further, the presence of rubber dam equipment affected the accuracy of the radiographs, and this was more apparent on the radiographs of the maxillary incisors and premolars compared to the mandibular incisors and premolars. Other problems identified included superimposition, indistinct and missed root apices. Methods to overcome these problems are suggested.
这项回顾性调查凸显了本科学生在牙髓X线摄影中使用平分角技术时所面临的一些问题。观察发现，上颌切牙和前磨牙的X线片比相应下颌牙齿的X线片有更大程度的失真。此外，橡皮障设备的存在影响了X线片的准确性，与下颌切牙和前磨牙相比，这在上颌切牙和前磨牙的X线片上更为明显。识别出的其他问题包括叠加、根尖不清晰和遗漏。文中提出了克服这些问题的方法。
