Four commercially available electric toothbrushes (Sonicare, Braun Electric Toothbrush, Interplak, and Blend-a-Dent) were assessed both for their operating characteristics and their ability to remove a food debris medium. The Sonicare and Blend-A-Dent have a lateral vibratory action, while the Interplak and Braun produce a rotary movement of the brush head. The vibratory action of the Sonicare was susceptible to loading. All devices produced both stable-pulsating cavitation and acoustic microstreaming that was demonstrated in vitro using a suspension of particles in water. Their effectiveness in removing a food debris medium was assessed with and without water. Three of the brushes (Sonicare, Braun, and Blend-a-Dent) were similar in their ability to remove the plaque, and all were superior to the Interplak; its streaming forces removed no food debris. The results indicated that the Blend-A-Dent was the most effective brush design in vitro, although the differences between Blend-a-Dent and Sonicare were not statistically significant.