A cross bite is the way a dentist would describe a certain way your teeth bite together.
In the majority of people, the top teeth bite slightly outside of the lower teeth, and in the front, the upper teeth overlap the lower teeth a little, as shown below.
Cross bites can happen at the front or the side, if there is a cross bite on the side, then it can look something like this:
In the photo above, all of the patients right teeth (left of photo) are in cross bite. If the cross bite is at the front, then it looks something like this:
Is a cross bite harmful
The answer to this really depends on the individual case. When there is a cross bite, there are often jaw joint issues. This is because when your jaw closes in its most comfortable position, the tooth or teeth in cross bite will deflect the jaw, and this pulls it into a less comfortable position.
You can only know if this is happening after a dentist (who understands jaw joints) examines you – It is rare that you feel any pain.
Because of this many people who have cross bites will have some degree of jaw clicking. Clicking in the jaw joint is the most obvious sign that the joint is not functioning correctly, and more often than not, this is due to the bite.
There are many degrees of jaw clicking, and some are easy to fix, and others are more complex, and may require more than just fixing the bite (occlusion).
How do you fix a cross bite
There are a few ways to fix cross bites, and the most common is to use some type of brace. The best brace type completely depends on the teeth in cross bite, and if there is enough room to correct the bite.
In some cases, braces alone will not fix the cross bite, this could be because the problem is the position of the jaw bones. Here it may be better to have surgery to correct the jaw bones (with braces at the same time), but thankfully it is rare someone will need this much treatment!
How do cross bites develop?
In most cases, we just don’t know! two of the most common reasons are:
1. Thumb Sucking
If you suck your thumb over the age of 6, then there is a tendency for the top back teeth to tilt inwards, and this will cause a cross bite on one side.
2. Jaw Position
In about 10% of people, the lower jaw is slightly down and forward, this will often cause a cross bite at the front. Many of these cross bites can be corrected with braces, however, as suggested above, some may be better treated with surgery.