Very accurate, durable and noiseless tools for many applications have been of great interest. Diamond-coated ultrasonic tools are excellent alternatives in this perspective, mainly for cutting hard materials. However, the conventional technology for diamond powder aggregation with nickel metallic binders could not withstand ultrasonic power. The diamond grains easily peel off and the tools were not durable enough while in contact with hard surfaces. This work presents studies concerning the deposition of CVD diamond coatings on different forms of metallic substrates, with very good adherence, to obtain abrading devices for an ultrasonic scaler used in odontology. This kind of technique is powerful for hard material cutting and polishing with very good accuracy and less noise. Concerning teeth cavity preparation it presents the additional advantages of less pain and no bleeding. Diamond coating has been obtained by using an Enhanced Hot Filament Assisted Technique, with high growth rate, using conventional hydrogen and methane gas mixtures. Small and special metallic rods machined in the form of odontological burs, with a pre-prepared surface, were coated with thick CVD diamond film. These CVD diamond tips were tested for their life time and cutting accuracy by an abrading enamel of tooth and glass surfaces with the use of ultrasonic scaler, showing very good performance. Ultrasonic CVD diamond tips are around 30 times more durable than conventional ones. In all tests, the cutting regions present no damaged edges and the bore diameter maintains accurate values while the tips lasts. The morphol-ogy and roughness analyses of the abraded surface have been evaluated by SEM and AFM techniques. An important application of this device in dentistry, presented for the first time, is also discussed.
