An “overbite” is the common term the public uses when the upper teeth protrude too far forward in relation to the lower teeth. The proper term for this relationship is actually called “overjet” (overbite actually describes the VERTICAL overlap of the front teeth!). No worry – I understand what is being described when I hear this term – what is important is: 1) What is causing the upper teeth to “stick out” too far in relation to the lowers, and 2) What should be done to correct this, and when?
How and when to correct an excess overjet is dependent on several factors, including the etiology (or “what is causing the issue?”), and the age and dental developmental stage of the patient. Lets take a look at several scenarios.
- The upper teeth are flared forward due to a thumb sucking habit. When a child sucks their thumb or finger for an extended amount of time, they are actually placing forces on the teeth that disrupt the equilibrium within the mouth. Even a very gentle force placed on the back of the upper teeth will make the teeth start to move, if that force is consistent (this is actually how braces work- they placed a light force on the teeth for an extended period of time). If we see that there is a thumb sucking habit with a child whose front permanent teeth have not erupted yet , we will often monitor the situation only and see if the habit will terminate itself over time. However, we will usually intervene if the habit persists when the permanent front teeth erupt, or we see that teeth are noticeably starting to move in an undesirable direction. In addition to making the front teeth flare, thumb sucking can also make the lower teeth tip back. The negative pressure created by thumb sucking can also make the upper arch collapse inward, causing a posterior crossbite. Obviously if their are problems to this extent, we will usually recommend treatment to help end the thumb sucking habit, usually with a habit guard that is bonded to the upper teeth, and often in conjunction with limited braces or an expander if needed.
- Upper teeth are too far forward due to a skeletal disharmony, or a growth issue with the upper or lower jaws. This is a relatively common cause for excess overjet, and is caused by the lower law not growing forward enough compared to the upper jaw, or the upper jaw growing forward too much. There has been much debate over many decades as to the best time to treat this condition. Most of the current research supports waiting to treat this when the patient is in their adolescent growth spurt, and we can take advantage of the body’s natural growth to help us out. We can often do this in one complete phase of treatment. Of course there are exceptions, such as the overjet being so large that it presents a trauma risk to the upper teeth during the late childhood years, social issues, or getting a head start on correcting this issue if there are other reasons that we are starting early orthodontic treatment (such as crossbites that are causing asymmetric shifts of the lower jaw, or creating space for teeth that are blocked out from erupting normally). In general though, I prefer to wait for the adolescent growth spurt if possible.
If there is any question at all about timing, please contact myself of your local orthodontist for guidance. We can detect this issues at a very early age (The American Association of Orthodontists recommend an initial exam around the age of 7), and can make a plan for the most ideal treatment and age to get started.
Dr. Dan Rejman is graduate of the University of Michigan at Ann Arbor School of Dentistry, and did his specialty training and orthodontic residency at Marquette University in Milwaukee, Wisconsin. He has been Board Certified by the American Board of Orthodontics since 2007.