Malocclusion and Orthodontics
What is malocclusion?
Malocclusion means having crooked teeth or a “poor bite.”
Orthodontic treatment can correct the way teeth and jaws line up. Dentists who are specially trained to correct malocclusion are called orthodontists. They use a variety of treatment tools and techniques (including braces) to move teeth, and sometimes the jaw, into the right places.
What causes malocclusion?
A common cause of malocclusion is teeth that have too much or too little room in the jaw. If children have a small jaw, their teeth may grow into a space that is too small. As a result, teeth may grow or drift out of place.
Other causes of crooked teeth include thumb-sucking, pacifier use, and tooth loss.
What are the symptoms?
The most obvious sign is teeth that are crooked or stick out. Malocclusion can range from mild to severe. Most of the time, having crooked teeth is only a cosmetic problem, meaning people don't like the way their teeth look. But in severe cases, it can cause problems with eating or speaking.
How is malocclusion diagnosed?
A dentist usually checks for malocclusion in children during regular dental visits. If the jaw or teeth are out of line, the dentist may suggest a visit to an orthodontist. The American Association of Orthodontists recommends that all children get a checkup with an orthodontist by age 7.
An orthodontist will:
- Ask questions about your or your child's past health problems.
- Check the mouth and teeth.
- Take X-rays of the face and teeth.
- Take photographs of the face and teeth.
- Make a plaster model of the teeth.
Start your child’s trips to the dentist at age 12 months. This will help your child get used to seeing a dentist. It will also catch any early problems. Keep up with regular dental checkups 2 times a year.
How is it treated?
In children and teens, the first step in treatment may be to take out certain teeth to make room for teeth that may still grow in.
The next step is to attach braces to teeth to straighten out the bite. In addition to straightening teeth, braces can help move a child’s jaw into the right position.
Teeth tend to move forward as you age, even after treatment with braces. Retainers are devices you wear in your mouth to keep your teeth from moving. Some people need to use retainers for many years after treatment.
Adults can successfully straighten their teeth with braces. But the only way to straighten an adult’s jaw is with surgery.
Braces and other types of orthodontic treatment cost a lot. Most insurance plans don't pay for them. Before you start treatment, make sure you know how much it will cost and how you will pay for it.
Frequently Asked Questions
Learning about malocclusion:
Getting orthodontic treatment:
Living with malocclusion:
Malocclusion (poor bite) is usually caused by problems in the shape or size of the jaw or teeth. If children have a small jaw, their teeth may grow into a space that is too small. Under these crowded conditions, teeth will push each other out of proper position. Other causes include thumb-sucking, pacifier use, and tooth loss.
People can inherit mismatched traits such as jaw size and tooth size. This can produce large, crowded teeth in a small jaw or small teeth that drift out of place in a larger jaw. In other cases, a person may inherit a trait that results in missing teeth or teeth that erupt in one another's place (transposed teeth). More rarely, people are born with conditions (congenital) that can create malocclusion problems, such as a cleft palate or a severely underdeveloped upper or lower jaw.
Oral habits that place ongoing or frequent pressure on the teeth may slowly move the teeth out of place. The most common oral habits that cause malocclusion include:
- Thumb- or finger-sucking and pacifier use for more than 4 to 6 hours within a 24-hour period.
- Mouth breathing (possibly). Infants and children may breathe through their mouths because of a partially blocked airway.
Tooth loss may cause drifting of bordering teeth into the empty space, creating a poor bite. Common causes of tooth loss are:
- Trauma, such as sports injuries and automobile and falling accidents.
- Tooth decay that leads to having a tooth pulled (extracted) by a dentist. Poor dental hygiene promotes tooth decay, as does a child sucking on a bottle during sleep. The sugars in milk, juice, and formula can cause damage to teeth. For more information, see the topic Tooth Decay.
The most obvious sign of malocclusion is crooked or protruding teeth. Physical symptoms of malocclusion are uncommon but can range from mild to severe. Have your general or pediatric dentist evaluate whether a poor bite is causing:
- Difficulty chewing food.
- Problems with biting the cheek or roof of the mouth.
- Slurring speech, trouble saying certain words, or other speech problems.
- Pain in the facial muscles or jaw.
- Permanent teeth coming in (erupting) at the wrong position.
Adult malocclusion symptoms will typically remain the same or get worse over the years. Symptoms in a child who has mild malocclusion may improve over time. Through the teen years, the jaw grows dramatically. This growth period may correct mild crowding of teeth or teeth shifting as a result of thumb-sucking.
Teeth that are naturally perfectly aligned are rare. A poor fit and alignment of the teeth (malocclusion) can range from mild to severe. Mild malocclusion causes no medical or functional problems and little cosmetic concern, while severe malocclusion may cause difficulty with eating and speaking. Some people are embarrassed or self-conscious about crooked or protruding teeth.
Crowding is the most common type of malocclusion. In children, early crowding of permanent teeth can prevent new teeth from coming in properly or from erupting at all (impaction).
Some mild types of malocclusion may improve as a child's jaw grows and changes. But there are many conditions that don't improve without treatment. These usually involve the size or position of the jaw (such as an underbite or an unusually narrow lower jaw).
With or without orthodontic treatment, the teeth have a normal tendency to slowly drift toward the front of the jaw. This may lead to crowded lower front teeth (incisors).
What Increases Your Risk
Factors that increase the risk of developing malocclusion include:
- A family history of malocclusion. Jaw and tooth size are inherited traits that can cause too much or too little room for the teeth.
- Oral habits, such as thumb-sucking and possibly mouth breathing.
- Tooth loss, due to trauma or tooth decay. After a
tooth is knocked out or removed (extracted), the bordering teeth
drift out of place. Major causes of childhood tooth
- Playing sports without a mouth guard.
- Using poor dental hygiene.
- Stumbling or falling accidents.
- Sucking on a baby bottle during sleep. The sugars in juice, milk, and formula can cause tooth decay.
When To Call a Doctor
- Call your dentist or orthodontist immediately for a dental emergency, such as the loss of a tooth or if a broken orthodontic device (appliance) prevents you from opening or closing your mouth. For more information, see the topic Mouth and Dental Injuries.
- Call for an appointment with your orthodontist or dentist if nonprescription pain relievers don't ease appliance-related pain or if your appliance has loose brackets or bands, distorted wires, or wires that are too long and irritate the inside of your cheeks.
Start your child's dental visits at a young age, both to help your child become familiar with a dentist and to watch for any early dental or malocclusion problems. Keep up with regular dental checkups (twice a year). For more information, see the topic Basic Dental Care.
Watchful waiting is when you and your doctor watch symptoms to see if a health condition improves on its own. If it does, no treatment is necessary. If symptoms don't get better or get worse, then it’s time to take the next treatment step.
Watchful waiting is often fine for children with malocclusion. Keep in mind that the early years, when the jawbone is still growing, are the best time for braces. Some people wait until they are adults before straightening their teeth. After you talk with a dentist or orthodontist about your or your child's situation, it’s usually up to you to decide the timing of treatment.
Who To See
A general dentist or a pediatric (children's) dentist can give dental care, a first checkup for orthodontic treatment, and simple orthodontic corrections.
Dentists who have 2 years or more of extra training in a specific area treat more complex dental problems. Dental specialists who treat different aspects of malocclusion are:
- Orthodontists , who straighten teeth.
- Prosthodontists, who replace missing teeth.
- Periodontists, who treat or prevent gum (periodontal) disease.
- Oral surgeons (maxillofacial surgeons), who surgically treat structural problems of the jaw, face, head, or neck.
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Exams and Tests
During routine dental visits, your dentist typically looks for developing malocclusion. Talk with your dentist about any oral habits (such as a child's use of a pacifier) or difficulties with speech, chewing, or pain. Your dentist may suggest an orthodontic evaluation.
An orthodontist will:
- Ask questions about your or your child's medical and dental history. He or she may ask if you have any allergies, especially to latex or nickel.
- Conduct a clinical exam, looking at
- Condition of teeth and gums.
- Jaw structure.
- Placement of the teeth in the jawbone.
- Fit between the upper and lower teeth.
- Jaw joint function.
dental X-rays, including panoramic (full view) and
profile X-rays, to check the jawbone and dental structure and to identify:
- Where the permanent teeth are in relation to the primary (baby) teeth.
- Any missing teeth or teeth that are blocked and unable to come in properly (impacted).
- The condition of the roots.
- The amount of bone supporting the teeth.
- Estimate a child's skeletal age and projected growth using an X-ray image of the wrist (hand-wrist radiograph).
- Photograph the face and teeth.
- Create a plaster model of the teeth.
Orthodontic treatment uses appliances, tooth removal, or surgery to fix the way teeth and jaws are aligned. There are many ways to treat poor bite (malocclusion). Expert opinions differ about when to start treatment. Your dentist or orthodontist may give you a choice between early or later treatment or may prefer one specific approach.
The general categories of orthodontic devices (appliances) are functional and fixed.
Functional appliancesuse the muscle action from speaking, eating, and swallowing to create forces that move teeth and align the jaws. See a picture of a functional appliance.
- Some functional appliances are removable, while others are bonded to the teeth.
- A functional appliance may fit between the upper and lower teeth (a splint) or may span across the mouth between the molars, pressing the bone outward.
Fixed orthodontic appliances are sets of wires and brackets cemented to the teeth. These are commonly called braces. Over a period of about 24 to 28 months, the wires are tightened and adjusted, gradually applying enough force to move the teeth (bone remodeling).
Retainers are removable appliances made of molded plastic and wire. They hold the teeth in place after braces are taken off. If the teeth start to move back out of position, the orthodontist may bond a short retaining wire to the back of some teeth. This wire will hold the teeth in place.
Child and adolescent treatment
The aim of treatment in the childhood and teen years is to move permanent teeth into place. The orthodontist will time the treatments to match your child's natural growth spurts.
Treatment for crowding, the most common malocclusion problem, may mean removing (extracting) some permanent teeth. But orthodontists avoid removing permanent teeth when they can.
The malocclusion treatments for children and adolescents are:
- Extraction (serial removal). Removing some baby teeth may ease severe crowding.
- Growth modification. This involves wearing fixed or functional appliances during the day and night to move the jaw into a better position.
- Fixed appliances (braces) gradually move the teeth. For children and teens, this treatment phase usually lasts about 24 months; for adults, about 28 months.
- Retainers. Retainers hold the teeth in place after orthodontic treatment. Some orthodontists recommend that retainers be worn for many years, because teeth have a natural tendency to drift out of place.
- Space maintainers, made of metal or plastic. Spacers keep the surrounding teeth from moving (drifting) into open spaces created when teeth are pulled or lost in an accident.
Orthodontic treatment for malocclusion is a popular option for adults, due in part to better technology. In the past, wide silver bands held braces in place. Today they are less obvious. Instead of the wide bands, a small metal or ceramic fastener is bonded to each tooth, and a narrow wire passes through the fasteners.
New options include:
- Clear plastic instead of silver wires.
- Lingual braces. These braces attach to the back of the front teeth.
- Removable clear plastic aligners (Invisalign). These are molded specifically for you.
Lingual braces and aligners don't work for everyone. They aren't options for children. Your orthodontist can tell you the best choices for your situation.
Orthodontic treatment for adults may also involve:
- Removal (extraction) of teeth to create more space.
- Orthognathic surgery of the jaw.
- A retainer, after braces are removed.
- Adjustments, such as grinding of high tips of teeth, to prevent continued or increased malocclusion for adults.
Most adults have little or no jaw growth. This means that surgery is the only way to correct jaw-related bite problems. Some adults may benefit from simply camouflaging, or hiding, a jaw-related problem. Using braces, the orthodontist can move the teeth so that they fit together, despite the jaw discrepancy. But surgery is the best way to treat more severe jaw problems.
What To Think About
Some cases of malocclusion clearly require orthodontic treatment to straighten teeth. In many cases, though, the decision is a matter of personal choice. Besides looking nice, straight teeth can improve how you bite, chew, and speak. They are also less prone to decay, gum disease, and injury.
The timing of treatment is ultimately up to you and your child or teen. Talk with your orthodontist about the pros and cons of treatment options.
Orthodontic treatment isn't an exact science. The average treatment time is about 2 years, but it can take longer than planned. Usually, adult treatment takes longer than a child's treatment. The treatment time can vary, so ask your dentist how long it may last for you.
After treatment ends, teeth often begin to shift. Molded plastic retainers, usually worn at night, help prevent this tooth movement. You may need a retainer for an indefinite amount of time.
Orthodontic treatment is costly. Most medical and dental insurance plans don't pay for orthodontics. Before deciding on treatment, ask about the projected cost, terms of payment, and terms of the treatment contract.
Orthodontic treatment doesn't pose risks to adults who have healthy teeth and gums. Adults who have gum (periodontal) disease, though, must first get treatment from a periodontist to avoid possible gum damage or tooth loss. Orthodontic treatment sometimes can make preexisting gum condition worse.
You can take steps to prevent tooth loss, which can lead to malocclusion.
- Use a mouth guard when playing sports.
- Prevent tooth decay by practicing good oral hygiene and getting regular dental cleanings. For more information, see the topic Basic Dental Care.
- Avoid putting a baby or toddler to bed with a bottle. The sugars in the liquid can cause tooth decay.
- See your dentist right away (within 2 hours) if you lose a tooth unexpectedly.
Early dental visits are needed for good preventive dental care. And it can help your child feel more comfortable at the dentist's office over time.
The Academy of Pediatric Dentistry recommends that children be first checked for developing malocclusion between the ages of 2 and 6.
The American Association of Orthodontists recommends that children have an orthodontic screening by age 7. A pediatric dentist may refer a child to an orthodontist when a dental evaluation suggests the need for orthodontic treatment.
Your orthodontist will give you instructions on caring for your teeth during treatment. These may include:
- Avoiding sticky and hard foods, such as gum, taffy, and nuts.
- Taking vitamins with fluoride.
- Using a retainer—a piece of molded plastic and wire (orthodontic appliance) worn in the mouth to hold the teeth in place after orthodontic treatment—as often and as long as recommended.
- Carefully brush your teeth after meals and snacks.
If your child has crooked or protruding teeth from an oral habit such as thumb-sucking, his or her teeth may begin to return to normal position when the habit stops. You can help your child stop an oral habit. For more information, see the topic Thumb-Sucking.
For tooth pain from newly installed or adjusted braces for malocclusion, take regular doses of nonprescription pain medicine, such as ibuprofen or acetaminophen, for 3 to 5 days. One study shows that 400 mg of ibuprofen taken 1 hour before braces are adjusted and 6 hours later helps relieve pain.1Do not give aspirin to anyone younger than 20 without a prescription because of the risk of Reye syndrome, a serious illness that can cause severe liver and brain damage.
Orthognathic surgery treats malocclusion by restructuring the jaw through cutting the bone and repositioning the bone segments.
Orthodontists may remove (extract) teeth to create more space for incoming teeth.
What To Think About
Surgery may be the only viable treatment for severe jaw-related problems. Surgeons only perform jaw surgery on adults, after the jaw has stopped growing.
Before deciding on orthognathic surgery, consider getting a second opinion from another surgeon or orthodontist.
Some adults with malocclusion may prefer to replace all or part of a tooth by having restorative dentistry, which is less costly and less time-consuming than orthodontic treatment.
Other Treatment Choices
A crown (restorative dentistry) can improve the appearance of front permanent teeth (incisors) that are properly spaced but crooked.
What To Think About
The timing of treatment is ultimately up to you. If you have different treatment options, interview your orthodontist or dentist about the pros and cons of each option.
Orthodontic treatment isn't an exact science. Treatment can sometimes take longer than planned. If teeth are likely to move after braces are removed, you may need to use a retainer for several months or years.
- Bernhardt MK, et al. (2001). The effect of preemptive and/or postoperative ibuprofen therapy for orthodontic pain. American Journal of Orthodontics and Dentofacial Orthopedics, 120(1): 20–27.
Other Works Consulted
- American Association of Orthodontists (2006). Why straighten teeth? Available online: http://www.braces.org/beautifulsmile/straighten/.
- American Dental Association (2008). Braces and orthodontics. Available online: http://www.ada.org/public/topics/braces_faq.asp.
- Harrison JE, Ashby D (2000). Orthodontic treatment for posterior crossbites. Cochrane Database of Systematic Reviews (1). Oxford: Update Software.
- Mihalik CA, et al. (2003). Long-term follow-up of class II adults treated with orthodontic camouflage: A comparison with orthognathic surgery outcomes. American Journal of Orthodontics and Dentofacial Orthopedics, 123(3): 266–278.
- Sarver DM, Proffit WR (2005). Special considerations in diagnosis and treatment planning. In TM Graber et al., eds., Orthodontics: Current Principles and Techniques, 4th ed., pp. 3–70. St. Louis: Elsevier Mosby.
|Editor||Kathleen M. Ariss, MS|
|Associate Editor||Pat Truman, MATC|
|Primary Medical Reviewer||Kathleen Romito, MD - Family Medicine|
|Specialist Medical Reviewer||Steven K. Patterson, BSc, DDS, MPH - Dentist|
|Last Updated||January 22, 2009|
Last Updated: January 22, 2009