Authors: Richards AG.
Title: The buccal object rule.
Journal: Dent Radiogr Photogr
Date: Jan 1980
Citation: 53(3):37-56
Category: Radiology and Imaging
Evidence-based Ranking: 5
Purpose/Objectives: To describe the buccal object rule (BOR) and its various applications in dentistry. Discussion: Philosophical paper that describes the BOR and how it can be applied in various ways in day to day dental procedures. The BOR is: when two different radiographs are made of a pair of objects, the image of the buccal object moves, relative to the image of the lingual object, in the same direction that the x-ray beam is directed. The successful application of the BOR requires that the two radiographs display clear images of the hidden object and of a second object, such as a part of an erupted tooth, the position of which is known. The horizontal angulation (HA) should be changed when attempting to localize a point relative to a vertical line, such as a root canal. The vertical angulation (VA) should be changed when attempting to localize a point relative to a horizontal line, such as the mandibular canal. Several clues and illustrations in using this technique are discussed in detail. Summary: Localization techniques for pathosis, supernumerary teeth, fractures and foreign bodies are important uses of the x-ray examination. The BOR can be a very useful diagnostic tool in these radiographic procedures.

ReviewerÂ’s Comments: Good article that is clinically relevant and presents a number of techniques that can and should be used in endodontic and other dental treatment.