Did you know that while the terms overbite and overjet are frequently used interchangeably, they are distinct from each other? Our dentists in Port Moody explain the difference and how we might be able to correct either issue with clear aligners.
What are overbites and overjets?
Overbites and overjets are two of the most common orthodontic issues people encounter. Though these terms are often used interchangeably, these two conditions are distinctly different.
Also sometimes referred to as a deep bite, an overbite occurs when one-third of the lower incisors are covered by the upper front teeth while your jaw is in a closed position. This issue is vertical in nature, which distinguishes it from an overjet — a horizontal orthodontic problem.
Often called "buck teeth", an overjet occurs when the upper front teeth protrude over the bottom teeth, creating a significant horizontal overlap.
While upper front teeth normally rest slightly in front of your lower teeth when your mouth is closed, any space of more than 2 millimetres will cause issues.
Overbites are vertical, while overjets are horizontal and cause the upper teeth to protrude pass the bottom teeth at an angle. However, with an overbite, the teeth stay straight (not on an angle) and downward.
How are overbite and overjet caused?
Overbites are commonly caused by the lower jaw being somewhat smaller than the upper jaw, resulting in the lower teeth resting behind the upper teeth and moving downwards as gradual wear on your teeth occurs.
Your upper teeth will tend to show more gum, while your upper front teeth sit slightly lower than the teeth beside them (canines or upper side teeth).
If a patient had a tongue thrusting habit or was allowed to suck on an object — usually a thumb or pacifier — for too long as a child, overbites may occur. Chewing on objects such as pens or erasers or biting nails can also cause this issue.
Similar to overbites, childhood habits such as sucking on a thumb or finger can lead to overjet when adult teeth start to emerge. Another common cause is that the lower jawbone (mandible) fails to keep up with development of the forward growth of the upper jawbone (maxillary). This growth disparity results in the bottom jawbone (and consequently, the teeth), becoming situated behind where they should be to achieve an ideal smile.
Overjet or overbite can also be caused by genetic factors.
What dental issues can develop due to overbite and overjet?
In extreme cases of overbite, the lower teeth may touch the gum tissue behind the upper front teeth, creating wear on the teeth and gum tissue.
With an overjet, your risk for damaging your teeth or fracturing them increases. Some overjets are barely noticeable as they are moderate, while others are more severe and can make it difficult to close your lips completely due to poor alignment of teeth. You may also notice challenges with chewing or biting.
Can an overbite or overjet be treated with clear aligners?
If the overbite or overjet is skeletal in nature, we would not recommend clear aligners and instead suggest speaking to your dentist to explore other options, such as surgery.
However, if the overjet or overbite is caused by one of the issues listed above, we may be able to treat the problem with clear aligners. The aligners will apply gradual pressure to your teeth to move them into corrected positions as prescribed by your dentist in a custom treatment plan. This will leave you with a straighter, more symmetrical smile.
The clear aligners also move your gum at the same time, keeping proportions in check. You will need to wear your clear aligners for about 22 hours each day, removing them to brush, floss, eat and drink.
Your teeth will progressively shift with the aligners, and you’ll switch to a new set approximately every two weeks. Your custom treatment plan could involve wearing as many as 26 trays, which equates to one tray every two weeks for 12 months.
Before you start your treatment, your dentist will be able to show you a preview of how your new smile will look by the end of your treatment. Take the first step to schedule a consultation with your dentist to learn if you are a candidate for clear aligners.