Now, turn that paper to the side and scribble in the other direction. The paper is now more completely covered. Turn it diagonal and scribble - even more covered. Cleaning your teeth works the same way. This is why different companies have different types of toothbrush heads to choose from.
Different brushes hit different parts of the teeth.
Just click on Account Login and then click on Current Toothbrush . From there, you may change the type of toothbrush you use. If the brush you choose is more expensive, you'll be charged accordingly for the upgrade.