A plastic strap with holes (Selecta band) is attached to an electric toothbrush and makes it possible to get a good grip.
The user needs help putting toothpaste on the toothbrush and turning the toothbrush on and off. He also needs help turning the toothbrush in the holder in order to reach all sides of the teeth.
The Selecta strap is no longer available. In Sweden Varsam has a product that can work the same way: An elastic strap with two loops that can be placed on flatware, etc (Strap, Item number: R6094); see varsam.se (last checked March 2017).
This tip is from 2015