As concern about indoor air quality increases, attention is being placed on the aerosol and splatter produced during dental procedures that involves airotor, ultrasonic scalers etc. With the advent of the droplet-spread disease (severe acute respiratory syndrome - SARS), the infection control procedures for aerosols is warranted. Aerosols quantify the contamination produced by ultrasonic scalers and airotors during scaling and cavity preparation procedures. When compared with the handheld curette used as a control, all ultrasonic scalers and airotor bur tips tested produced significant aerosol and splatter regardless of the type of scaler and speed of the aerator instrument. The recommended method for controlling contaminated aerosol and splatter is the use of a large-bore high-volume evacuator for ultrasonic scalers and controlled speed for airotor instrument.