Posts for: June, 2021
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.”
Bite problems aren't limited to teeth simply out of position. The problem could be some teeth aren't there—visibly, that is. They still exist below the gums and bone, but they've been crowded out and blocked from erupting. We call this condition impaction.
Any tooth can become impacted and affect the bite, but a person's smile suffers more if it involves visible front teeth. This is especially so if the teeth in question are upper canines or "eye teeth"—the smile doesn't look normal without these pointed teeth on either side of the central and lateral incisors.
Impacted teeth can also contribute to more than a cosmetic problem: they're more susceptible to abscesses (pockets of infection) or root damage both to themselves or neighboring teeth. To minimize these potential health issues, we'll often remove impacted teeth surgically (as is often done with wisdom teeth).
But because of their important role in not only appearance but also bite function, we may first try to assist impacted canines to fully erupt before considering extraction. It takes a bit of orthodontic "magic," but it can be done.
Before we can make that decision, though, we want to precisely locate the impacted teeth's positions and how it may affect other teeth. This initial evaluation, often with advanced diagnostics like CT scanning or digital x-rays, helps us determine if the impacted teeth are in a workable position to save. If they're not, we may then need to consider removing them and ultimately replacing them with a dental implant or similar restoration.
But if their position is workable and there are no other impediments, we can proceed with helping them erupt. To do this we'll have to first expose them by creating a small opening in the gums through minor surgery. We then bond a small bracket to the tooth, to which we'll attach a small chain that we then attach to orthodontic braces. This enables us to exert continuous pressure on the tooth.
Over time, the pressure coaxes the tooth to erupt. We may still need to apply other forms of orthodontics and cosmetic procedures, but using this procedure to rescue impacted canines can produce a healthier and more attractive smile.
If you would like more information on treating complex bite problems, 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 “Exposing Impacted Canines.”
The straightening process for a crooked smile doesn't end when the braces come off. There's one more crucial phase to undergo to make sure we don't lose the progress you've achieved: wearing an orthodontic retainer.
Although often viewed as a nuisance, retainers are important because they prevent realigned teeth from reverting to their old positions. This is possible because the periodontal ligament, the gum attachment that allows us to move teeth in the first place, can contain “muscle memory” that naturally tries to draw teeth back to where they once were.
A retainer prevents this from happening: During wear the subtle pressure they exert keeps or “retains” the teeth in their new positions until they're firmly established, usually after several months. While most patients initially wear a retainer around the clock, this will gradually taper off until they're worn primarily during sleep hours.
While retainers come in many different styles and sizes, most fall into one of two categories: removable or non-removable (bonded). The first type, a custom-made appliance a patient can easily take in and out of the mouth, has its advantages. Removing it makes it easier to clean the teeth. They're also adaptable to reduced wear schedules for eating, brushing and flossing, or for special occasions.
But a removable retainer may be noticeable to others. Its removability can also lead to problems. Out of the mouth they're prone to be lost, resulting in additional replacement costs. And immature patients may be easily tempted to take them out too often—or not wear them at all.
A bonded retainer solves many of these potential problems. Because the retainer wire is securely bonded to the back of the teeth, it's not visible to others. And because it can't be removed except by an orthodontist, there's virtually no chance of losing it or haphazard wear.
On the other hand, bonded retainers can occasionally break, requiring repair or replacement. And flossing is more difficult than with a removable retainer, although a little training from a dental hygienist can make that easier.
The choice of retainer depends on the individual and their priorities. But whether removable or bonded, a retainer is absolutely essential for protecting your new, hard-earned smile.
If you would like more information on bonded retainers, 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 “Bonded Retainers.”