Overbite, underbite and crooked teeth

Is an overbite normal?

A small overbite is normal and helps with healthy function, according to Cleveland Clinic, which describes an overbite as present when the overlap exceeds about 2 to 4 millimeters. It says an overbite is often called a deep bite, and differs from overjet, which is horizontal. An overbite that is larger than normal is a type of malocclusion.

Is an overbite bad?

It can be if it is pronounced. Cleveland Clinic lists tooth erosion, cavities and gum disease, jaw pain, temporomandibular disorders and pain when chewing, breathing issues and speech challenges, and, if untreated, headaches, earaches, neck pain and difficulty chewing. Mild overbites may not need treatment, and an orthodontist can tell you which side yours falls on.

What causes an overbite?

Cleveland Clinic names genetics, such as inherited jaw shape that can run in families, and habits such as nail biting, teeth grinding, tongue thrusting and thumb sucking or pacifier use past age 3. The AAO says underbites can be dental, skeletal or combined, with contributors including genetics, uneven jaw growth and childhood habits such as thumb sucking, prolonged pacifier use, tongue thrusting and mouth breathing.

Do I have an overbite?

Look in the mirror with your back teeth together. If the upper front teeth cover the lower by more than a small amount, you may have an overbite, and for an underbite the lower front teeth sit in front of the upper. The AAO lists signs of an underbite: lower teeth biting in front of the upper, a prominent lower jaw or chin, chewing or speech difficulty, jaw pain, uneven tooth wear and strain closing the mouth. Only an orthodontist can diagnose and tell whether it is dental or skeletal.

Are crooked teeth genetic?

Inherited traits such as jaw shape can affect tooth alignment, according to Cleveland Clinic, so crooked teeth can run in families. The sources we read for this guide do not cover other causes of crooked teeth in detail. Habits like thumb sucking can contribute, as above.

Does flossing create gaps in teeth?

The sources we read do not say that it does, and we found no source linking flossing to gaps. Gaps can come from jaw and tooth size, habits or gum disease, and a new gap deserves a dentist's check. Our flossing guide explains how to floss gently.

How is it fixed, and how long does it take?

Braces, aligners, growth-guiding appliances in children and sometimes jaw surgery in adults are the main options, as our guide on fixing an overbite explains. Healthline says traditional braces are usually worn for one to three years, with a retainer afterwards. Cleveland Clinic says the time depends on your situation.

Why see an orthodontist early?

The AAO recommends a first orthodontic evaluation by age 7, since early treatment offers more options, and says many mild underbites caught early can be treated without surgery. ADA MouthHealthy says orthodontic treatment can be started at any age, and many adults seek it.

Questions to ask an orthodontist

A consultation is the best way to find out whether a bite problem needs treatment and what kind. Written answers make options easier to compare.

• Is my bite problem dental, skeletal or both?
• Do I need treatment now, later or not at all?
• Which options suit my case, and how long will each take?
• What will I need afterwards, such as a retainer?
• What happens if I decide to wait?

Guides in this topic

Frequently asked questions