Introduction: The objective of this 2-arm parallel trial was to determine the plaque removal efficacy (main outcome) and the motivation assessment (secondary outcome) comparing a manual versus an interactive power toothbrush in orthodontic patients. Methods: Sixty adolescents with fixed orthodontic appliances in both arches were randomized in a 1:1 ratio in this parallel, randomized, examiner-blind controlled clinical trial. Eligibility criteria included at least 16 natural teeth, 1-6 "focus care areas," plaque score of $1.75, no severe caries, gingivitis and periodontitis, no dental prophylaxis, no smoking, no antibiotics, and no chlorhexidine mouth rinse. Subjects were to brush unsupervised with either an interactive power toothbrush (Oral-B Professional Care 6000, D36/EB20) with Bluetooth technology or a regular manual toothbrush (Oral-B Indicator 35 soft). Focus care areas were each brushed for 10 additional seconds. Plaque removal was assessed with the use of the Turesky Modification of the Quigley-Hein Plaque Index (TMQHPI) to determine change from baseline at 2 and 6 weeks. Supervised brushing at screening and post-treatment visits recorded actual brushing times. Subject-reported motivational aspects were recorded at screening and week 6. Results: Fifty-nine subjects aged 13-17 years completed the study. The interactive power toothbrush provided significantly (P\0.001) greater plaque reduction versus the manual toothbrush at 2 and 6 weeks according to the whole-mouth TMQHPI. The treatment difference in adjusted mean plaque change from baseline was 0.777 (95% CI 0.614-0.940) at week 2 and 0.834 (0.686-0.981) at week 6. Mean reductions in the number of focus care areas were also significantly greater (P \0.001) in the power brush group at weeks 2 and 6. Brushing times increased significantly at weeks 2 and 6 (P #0.013) versus baseline in the interactive power brush group only. Subject-reported motivation was significantly increased in the interactive power brush group at week 6 versus screening (P #0.005). Conclusions: An interactive power toothbrush generated increased brushing times and significantly greater plaque removal versus a manual brush. (Am J Orthod Dentofacial Orthop 2019;155:462-72)