The role of the bitewing roentgenogram in dentistry is reviewed, including the roentgenographic techniques used, accessories for stabilisation of the film, and execution of the roentgenograph. Common errors in application of the technique are listed. The literature on the bitewing roentgenogram is surveyed and the conclusion stated that this roentgenographic technique is a diagnostic instrument that has no substitute for the purpose of detecting incipient interproximal carious lesions and periodontal diseases in the early stages of affecting the alveolar bone. No dental examination can provide complete diagnosis without bitewing roentgenograms.