Picking out a toothbrush used to be simple. But these days, consumer choices include everything from ergonomically designed brushes that jiggle and beep to those with slanted or staggered bristles that change color and good-grip handles that bend. Which is good. But unless your dentist recommends otherwise, brush twice a day for at least two minutes. And use a soft-bristled toothbrush whose size and shape fits your hand and allows you to reach the surfaces of every tooth.
Harms also reminds that brushes wear out.
Once the bristles become worn or splayed, the brush can't clean your teeth well and may even injure your gums. So, toothbrushes should be replaced every three or four months, or sooner if you notice the bristles become worn. Dr. Harms is quick to add one other note. Your toothbrush can't reach areas between the teeth. So it's also important to clean between the teeth daily with floss or interdental cleaners.