The brush skew in relation to the teeth brushed in order to limit the tooth and gum.
We start from the back teeth and gradually move to the back teeth on the other side.
Similarly both brushed off the side (facing the cheek) and the inside (facing the tongue).
In areas behind the upper and lower teeth do not fit because the toothbrush is placed vertically.
Finally, the toothbrush is placed vertically on the chewing surfaces of back teeth.