Whether you use an electric or a manual toothbrush, clean your teeth as normal and then change hands and go over them again.
Why? Because the angle that the tooth brush filaments make when brushing with your other hand is different, it gives a cleaner finish.
It feels kinda funny at first but it reduces the chances of tooth decay and makes your mouth feel even cleaner, no bad thing!
So, brushing your teeth with both hands is the best way to clean your teeth and reduce your treatment visits to the dentist.