A modification of the bisecting-angle technique for anterior periapical dental radiographs.

A modification of the standard bisecting-angle technique for periapical views of incisor teeth is presented. The technique involves a constant x-ray cone position, which is perpendicular to the floor for maxillary incisors and parallel to the floor for mandibular incisors. The periapical film is held between the incisor teeth as if it were an occlusal film for all anterior periapical radiographs. Tracings from lateral skull radiographs, taken of dried skulls of various ages, were used to determine the optimal angle between the periapical film and the floor to produce a dimensionally accurate periapical view of the incisors. The technique is suggested as an alternative to the standard bisecting-angle technique and the parallel technique. It is intended for anterior periapical radiographs when clinical conditions make conventional techniques difficult. For example, it can be used in very young children, patients with gagging problems, and patients with narrow lower jaws or large muscular tongues.