Dental hygienists’ use of ultrasonic instrumentation has grown steadily during the last 25 years. The number of ultrasonic units and tips available has also increased. The 2 types of ultrasonic instruments in use are magnetostrictive and piezoelectric. Magnetostrictive units are the most popular in the United States, while both units are widely used in Europe and Asia. Research comparing these 2 types of ultrasonic scaling devices has shown that both methods are equally effective in terms of calculus removal. Overall, the research is not conclusive regarding which type is better than the other. One study showed that the piezoelectric scaler was more efficient than the magnetostrictive scaler in removing calculus but left the instrumented tooth surface rougher. Yet, a previous study that compared the effect on root surfaces of 3 ultrasonic scalers to a periodontal curet showed that the curet produced the smoothest surface and the 2 piezoelectric scalers both produced smoother tooth surfaces than the magnetostrictive scaler. CRA Associates, an independent product evaluation service, has rated both types of units very highly in past evaluations. The effectiveness of these instruments is determined by the clinician’s experience, technique, and the type of patient being treated. Therefore, questioning if one type of scaler is better than another is a matter of personal preference that can only be determined after the clinician has used the ultrasonic scaler, preferably on a number of patients with various degrees of periodontal disease.