Oral B does have a variety of replacement brush heads that fit one handle (not all fit all handles, so check). I use the round head for sensitive teeth & gums. According to my dentist, the round-headed ones, not the cross-action ones, are best if you have gum recession. Since I did not grow up with electric toothbrushes, I was moving it like a manual toothbrush, but learned that you are NOT supposed to "brush" with an electric toothbrush, just angle it at 45 degrees to the base of the teeth and very slowly move it along the gum line. Actually, the rotation of the head will walk it along the gum line while you guide the handle with a light touch.