The surface changes in archwires and brackets caused by air-polishing devices when applying the Clinpro Prophy and Air-Flow((R)) powders can be considered as marginal overall. When the adjacent periodontium is intact, both powders are equally suitable, although the Air-Flow((R)) powder is somewhat more effective due to its greater abrasiveness. When using plastic brackets, Clinpro Prophy proved to be the powder of choice, thanks to its low abrasiveness.