Powered toothbrush was basically designed to aid persons with decreased motor skills viz. physically challenged persons and special children, but in case of normal persons the normal toothbrush is preferred to powered.
1. Yaacob, M., Worthington, H. V., Deacon, S. A., Deery, C., Walmsley, A. D., Robinson, P. G., & Glenny, A. M. (2014). Powered versus manual toothbrushing for oral health. Cochrane Database of Systematic Reviews, (6).
2. Forrest, J. L., & Miller, S. A. (2004). Part II: Manual versus Powered Toothbrushes: A Summary of The Cochrane Oral Health Group's Systematic Review. Journal of Dental Hygiene, 78(2).
de Jager M, Rmaile A, Darch O, Bikker JW. The effectiveness of manual versus high-frequency, high-amplitude sonic powered toothbrushes for oral health: A meta-analysis. J Clin Dent 2017;28(1 Spec No A):A13-28. Article The Effectiveness of Manual versus High-Frequency, High-Ampl...
There once was a report that ultrasonic toothbrushes were slightly better for patients with severe periodontal disease. Otherwise, no difference. I recommend an extra soft normal toothbrush.