Extraoral Periapical Radiography: A Technique Unveiled

Abstract

Introduction: Extraoral periapical radiography (EOPAR) is a technique where the film is placed extraorally overlying the tooth of interest and the X-ray beam is directed from the opposite side of the face. This technique was first proposed by Newman and Friedman (2003) and later modified by Chia-Hui Chen et al (2007) to assist certain patient populations who are unable to tolerate intraoral films/sensors. Materials and methods: An experimental case study was designed using dry skulls. The modified beam aiming device was assembled and positioned accordingly to the tooth of interest at vertical angulations of - 20 to - 30 for maxillary teeth and + 20 to + 30 for mandibular teeth. The X-ray beam was directed from the opposite side toward the film/sensor placed extraorally on the contralateral side. Once, the exposure parameters were established on dry skulls, the technique was validated on human volunteers. Results: A series of clinically useful radiographic images of the maxillary and mandibular premolars and molars were obtained using EOPA radiographic technique. Conclusion: EOPAR technique can be used to produce diagnostically useful radiographs of the maxillary and mandibular teeth. It is an effective approach for obtaining periapical radiographs in certain patient populations who are unable to tolerate intraoral films and/or sensors. Although this technique is not intended to be a substitute for conventional intraoral radiography, it is a useful supplement to our clinical practice.