Oral-B was founded by a dentist, and to this day Oral-B products, including Oral-B brush heads are dentist-inspired to help you get the best clean possible. No matter what you choose to brush with, it’s important to keep in mind how often you should change your toothbrush or brush head. Dentists recommend replacing your brush head every 3 months. That’s because bristles can become frayed and worn-out overtime resulting in a less than optimal clean.