The Use of Film Holding, Beam Collimating and Aiming Devices in Bitewing Radiography

Bitewing radiographs aid the diagnosis of approximal dental caries in contacting posterior teeth, and allow the sessment of interdental bone height, calculus deposits and restorations. Comparison of serial films allows the monitoring of both disease activity and therapy. Such comparisons are only valid if films are standardised with respect to angulation, distance, exposure and processing. The use of film holders and beam aiming instruments greatly assists standardisation of many of these variables. The evolution of various designs reveals certain desirable features such as: additional collimation of the x-ray beam, rigid connection between film holder and x-ray tube, and a method for relocation. Although step wedges have been advantageously incorporated into periapical film holders, they apparently have yet to be used with bitewings. A new bitewing film holder and aiming device is described which aids standardisation of the technique with the minimum of delay. This design rigidly connects the film holder to the tube head, incorporates additional beam collimation, a metal film backing plate and a locating ramp. A step wedge is positioned so that its image appears on the film without masking any diagnostic information. The routine use of bitewing film holders and aiming devices is advocated.