I've never believed an electric tooth brush could do the work of a manual. But after years of fillings other dental work, I recently switched to a new dentist who recommended this tooth brush and I purchased it in her office. 6 months later, I went back for my cleaning, No Cavities and no tarter. And the timer is so convenient, I know exactly how long to brush. And there is a smaller replaceable head that I use on my 4 year old, hopefully starting early will keep her from having the same dental issues I've had. I will never go back to a manual brush.