While crooked teeth are usually responsible for a malocclusion (poor bite), the root cause could go deeper: a malformed maxilla, a composite structure composed of the upper jaw and palate. If that’s the case, it will take more than braces to correct the bite.
The maxilla actually begins as two bones that fit together along a center line in the roof of the mouth called the midline suture, running back to front in the mouth. The suture remains open in young children to allow for jaw growth, but eventually fuses during adolescence.
Problems arise, though, when these bones don’t fully develop. This can cause the jaw to become too narrow and lead to crowding among the erupting teeth and a compromised airway that can lead to obstructive sleep apnea. This can create a cross-bite where the upper back teeth bite inside their lower counterparts, the opposite of normal.
We can remedy this by stimulating more bone growth along the midline suture before it fuses, resulting in a wider maxilla. We do this by installing a palatal expander, an appliance that incrementally widens the suture to encourage bone formation in the gap, which over time will widen the jaw.
An expander is a metal device with “legs” extending out on both sides and whose ends fit along the inside of the teeth. A gear mechanism in the center extends the legs to push against the teeth on both sides of the jaw. Each day the patient or caregiver uses a key to give the gear a quarter turn to extend the legs a little more and widen the suture gap. We remove the expander once the jaw widens to the appropriate distance.
A palatal expander is an effective, cost-efficient way to improve a bite caused by a narrow jaw, but only if attempted before the bones fuse. Widening the jaw after fusion requires surgery to separate the bones — a much more involved and expensive process.
To make sure your child is on the right track with their bite be sure to see an orthodontist for an evaluation around age 6. Doing so will make it easier to intervene at the proper time with treatments like a palatal expander, and perhaps correct bite problems before they become more expensive to treat.
If you would like more information on treating malocclusions, please contact us or schedule an appointment for a consultation. You can also learn more about this topic by reading the Dear Doctor magazine article “Palatal Expanders: Orthodontics is more than just Moving Teeth.”
A poor bite (malocclusion) could be more than simply teeth out of alignment. There could be complex causes for the malocclusion, possibly involving the facial bone structure.
An example of this is the development of a cross-bite due to problems with the upper jaw and palate (the roof of the mouth), jointly called the maxilla. The maxilla is in fact formed by two bones fused together in the center of the palate in what's called the midline suture. The suture doesn't completely fuse until after puberty.
Sometimes a maxilla's development doesn't follow a normal track. The upper jaw doesn't widen as it should, which leads to the cross-bite where the upper back teeth abnormally bite inside the lower teeth. The upper front teeth continue to bite normally in front of the lower front teeth. This also can have profound influence on breathing, causing sleep apnea.
We can correct this by using an orthodontic appliance called a palatal expander before the midline suture fuses. The expander gradually widens the upper jaw to its normal width and thus eliminates the cross-bite.
Positioned at the roof of the mouth, the expander has metal arms that extend from a central hinge to exert pressure on the inside of the upper teeth. The patient or a caregiver uses a small key to turn a mechanism that extends the arms toward the teeth a tiny amount each day. This gradually widens the jaw, while at the same time stimulating bone growth at the midline suture. Eventually the gap fills with bone to solidify the new width as the suture fuses.
It's important to undertake this treatment before fusion. If you wait until after puberty, you will need to separate the bones first to attempt it. The overall impact and cost is much less if you act promptly in the early years.
Palatal expansion may not be the right treatment in every case, so we'll need to perform a thorough orthodontic exam first. If, however, we do determine it can help, using an expander can improve function, correct future breathing problems and make possible a more attractive future smile.
If you would like more information on orthodontic treatment options, please contact us or schedule an appointment for a consultation. You can also learn more about this topic by reading the Dear Doctor magazine article “Palatal Expanders: Orthodontics is more than just Moving Teeth.”
People mainly identify orthodontics with braces. But while they’re a major part of it, braces aren’t the only way this important dental specialty can make a difference in a person’s bite.
For example, orthodontics can help guide the development of a younger patient’s facial structure that could head off future upper teeth misalignment. The area of focus is the upper jaw and palate (the roof of the mouth) that jointly make up a structure called the maxilla. The maxilla is actually formed by two bones fused together in the center of the palate along what is known as the midline suture running from front to back in the mouth.
The two bones remain separated until puberty, which helps accommodate rapid structural growth during childhood. But problems can arise if the upper jaw is too narrow, causing a “cross-bite” where the lower back teeth bite abnormally outside the upper ones. This can crowd upper permanent teeth and cause them to erupt improperly.
Using a technique called palatal expansion we can correct this abnormality if we act before the maxillary bones fuse. The technique employs a custom-made appliance called a palatal expander that attaches to the posterior teeth of the upper arch. Expanders have two halves joined by a small screw device to increase tension against the teeth to widen the jaw. A parent or the patient (if old enough) increases the tension by using a special key to turn the adjustment screw a tiny amount each day. This may cause minor discomfort that normally eases in a few minutes.
The patient wears the device until the jaw expands to the desired width and then allows the bones to stabilize in the new position. This can sometimes create a small gap between the upper front teeth, but it often closes on its own or it may require braces to close it.
While palatal expanders are not for every case, they can help normalize development and improve the bite, and thus preclude more extensive orthodontic treatment later. But time is of the essence: after the maxilla has fused, surgery will be necessary to separate them and widen the palate. It’s important then not to delay if your child could benefit from this effective treatment.
If you would like more information on palatal expanders and other orthodontic treatments, please contact us or schedule an appointment for a consultation. You can also learn more about this topic by reading the Dear Doctor magazine article “Palatal Expanders.”