Dentist located in: OR
Dentistry.com dental articles & forum
Home Conditions Treatments Dental Daily Care Dental Forum Product Showcase Are You a Dentist?
Looking for a
Dentist for Bite Problems?
Do you have dental coverage?
Home > Dental Conditions > Malocclusion > Underbite Information
Bookmark and Share

Underbite Information: Over, Under and Through!


An underbite is a type of malocclusion that is signified by the abnormal protrusion of the lower jaw, or simply, when the bottom jaw and teeth stick out beyond the top jaw. It is the exact opposite of an overbite, where the upper jaw noticeably protrudes beyond the lower jaw.

Underbites are far less common than overbites. Whereas about 70 percent of the population has some form of an overbite, only 5-10 percent of the population suffers from an underbite, according to eBody.com. Although less common, underbites can be more extreme and may require more invasive underbite treatment if not corrected early.

Underbite Causes

Underbite - Underbites are a relatively uncommon form of malocclusion.

Underbites are often the result of a malformation in either the lower or upper jaw during growth, resulting in a lower jaw that is larger than its counterpart. Like most bite problems, most underbites are hereditary, meaning if someone in your family had an underbite, you're more likely to have one, too. An interesting theory explored on Wisegeek.com also links underbites to genetics. There are breeds of animals in which almost the entire species has an underbite, such as bulldogs. This may give us more information as to why some cultures are more prone to underbites than others. For example, the percentage of those who have an underbite is higher among Asians than the rest of the population, leading to the belief that underbites could be a genetic trait of some Asian cultures.

Underbites may result from environmental factors as well. Bad oral habits, such as tongue thrusting, mouth breathing and poor chewing habits can cause an underbite to form. These habits cause the tongue to reposition itself at the base of the mouth, pushing against the lower jaw and teeth and forcing them into an abnormal position. These habits are often formed early on in childhood and should be corrected in order for underbite treatment to be successful. If tongue thrusting or mouth breathing continues, the results could be reversed.

Underbite Treatment for Children

Depending on the severity of the case, underbite treatment may consist of a combination of orthodontics, tooth extractions or oral surgery. While dental treatment for underbites is available for patients of any age, it's highly recommended that it start early to hopefully prevent the need for surgery. Your jawbone continues to grow until about the age of 8, making underbite treatment easier in children as their jaws are easier to reshape.

Early treatment may exist in several stages:

Maxillary Expansion -- If the lower jaw is outgrowing the upper jaw, an expander may be placed on upper jaw to promote growth. An expander is an oral appliance that's fixed to the roof of mouth. During the first few months of treatment, the expander is widened with the turn of a key. Once the desired width is achieved, the expander stays in to prevent teeth from moving back. This type of underbite treatment can take about a year and is often followed by a retainer. Maxillary expansion should be performed before jaw growth is complete and is usually only recommended for children under the age of 8.

Reverse-Pull Headgear -- If the expander doesn't completely correct the underbite, headgear may be needed. Reverse-pull headgear, or protraction headgear, consists of a facemask that rests against the forehead and chin. The facemask is anchored to the mouth with rubber bands that are attached to metal bands on the top back molars. The pressure exerted between the two encourages the upper jaw to grow forward. Reverse-pull headgear is often worn at night, but your dentist may recommend that your child wear it for longer periods of time to correct his or her underbite.

Chin Cap -- For severe underbites, a reverse-pull mask may be combined with a chin cap, which wraps from the chin to the top of the head to restrain the lower jaw from growing.

Orthodontic Treatment or Surgery -- Even with early intervention, dental braces or retainer therapy may still be needed to complete your child's underbite treatment. While early intervention is meant to help prevent the need for surgery, it does not entirely eliminate the possibility of it. Your child will need to be monitored following his or her initial underbite treatment to determine what, if any, follow-up procedures are necessary in the future.

Underbite Treatment for Adults

If you're an adult with an underbite, it's not too late to correct it. But depending on the severity of your case, the type of underbite treatment you need will depend on whether your underbite is dental or skeletal. If the adult underbite results from the placement of the teeth (dental), orthodontic treatment will be required. A skeletal underbite (one that results from the formation of the jaw) will require surgery to push back the lower jaw or move the upper jaw forward. Most underbites that are corrected with surgery also require braces before and after the procedure to complete treatment.

If you have an underbite, make an appointment to visit the dentist. While having surgery to correct an underbite isn't ideal, it is better than the alternative. The pressure that underbites put on your jaw can lead to TMJ, jaw pain, difficultly in chewing and several dental problems from lost enamel. You don't have to live with an underbite.

If you're interested in finding a dentist for underbite treatment, call us at 1-866-970-0441 today.

Bad Breath
Cleft Palate
Cold Sores
Dental Anxiety
Dental Emergency
Gum Disease
Mouth Problems
Oral Cancer
Sleep Apnea
Teeth Problems
Wisdom Teeth
See All
Cosmetic Dentistry
Dental Braces
Dental Implants
Dental Restorations
Exams & Cleaning
Fillings & Sealants
Gum Disease Treatment
Oral Surgery
Root Canal Therapy
Sedation Dentistry
Teeth Whitening
Tooth Extractions
See All
Dental Financing
Dental Hygiene
Nutrition Information
Overall Health
Pediatric Dentistry
Senior Dental Care
Your Dentist Visit
See All