Did you know that the terms overbite and overjet are frequently used interchangeably but are not interchangeable? Our orthodontists in Calgary explain the differences and how Invisalign Clear Aligners can help with either problem.
What are overbites and overjets?
Overbites and overjets are two of the most common orthodontic issues. Though the terms are often used interchangeably, there are distinct differences between these two conditions.
Overbite
An overbite, also known as a deep bite, occurs when one-third of the lower incisors are covered by the upper front teeth while your jaw is closed. The vertical nature of this problem distinguishes it from a horizontal overjet.
Overjet
Commonly called “buck teeth” an overjet is when the upper front teeth protrude over the bottom teeth, creating a significant horizontal overlap.
While it’s normal for upper front teeth to rest slightly in front of your lower teeth when closing your mouth, any space of more than 2 millimetres will cause issues.
Overbites are vertical, whereas overjets are horizontal and cause the upper teeth to protrude at an angle past the bottom teeth. An overbite, on the other hand, causes the teeth to remain downward or straight (not on an angle).
How are overbite and overjet caused?
The most common cause of overbite is that the lower jaw is slightly smaller than the upper jaw, causing the lower teeth to rest behind the upper teeth and move downwards as your teeth wear.
Your upper teeth will have more gum showing, and your upper front teeth will be slightly lower than the teeth next to them (upper side teeth, or canines).
Overbites can occur if a patient had a habit of thrusting his or her tongue or if he or she was allowed to suck on an object - usually a pacifier or thumb - for an extended period as a child. This problem can also be caused by biting the nails or chewing on objects such as erasers or pens.
Childhood habits such as finger or thumb sucking, like overbites, can cause overjet if they continue when adult teeth begin to emerge. Another common cause is that the lower jawbone (mandible) fails to keep up with the development of the upper jawbone's forward growth (maxillary). Because of this growing disparity, the bottom jawbone (and thus the teeth) end up being positioned behind where they should be for an ideal smile.
Genetic factors can also cause overbite or overjet.
What dental problems can overbite and overjet create?
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 chances of damaging or fracturing your teeth increase. Some moderate overjets are barely noticeable, whereas others are more severe and can make it difficult to close your lips completely due to poor tooth alignment. You may also experience difficulty chewing or biting.
Can an overbite or overjet be treated with Invisalign Clear Aligners?
If the overbite or overjet is skeletal, we would not recommend Invisalign Clear Aligners and instead suggest speaking to your dentist to explore other options, such as surgery.
If the overjet or overbite is caused by one of the issues listed above, we may be able to treat it with Invisalign Clear Aligners. The aligners will gradually push your teeth into the correct positions prescribed by your dentist in a custom treatment plan. This will result in a more symmetrical, straighter smile.
The Invisalign Clear Aligners also move your gums at the same time, which helps to maintain proportions. You must wear your Invisalign Clear Aligners for approximately 22 hours per day, removing them only to brush, floss, eat, and drink.
The aligners will gradually shift your teeth, and you'll change to a new set every seven days. Wearing as many as 52 trays, which equates to one tray every week for 12 months, could be part of your personalized treatment plan.
Before you begin treatment, your dentist will be able to show you a preview of how your new smile will look at the end. Schedule a consultation with your dentist to see if you are a candidate for Invisalign Clear Aligners.