An evaluation of the S. S. White Panorex® dental x-ray machine was performed. The physical and operational characteristics of the unit were investigated with particular emphasis on kVp and mA meter calibrations, focal spot characteristics, x-ray beam dimensions, half-value layers, and inherent filtration. Isoexposure curves for radiation in the vicinity of a phantom were determined, and survey techniques for half-value layer measurements and x-ray beam alignment were investigated. Recommendations based on the observed operation of the Panorex are advanced.