Underbite vs Overbite, Teeth Surgery, Braces, Correction Before and After, Jaw Meaning

An underbite is a dental condition where the lower jaw extends beyond the upper jaw, causing the bottom teeth to protrude in front of the upper teeth. It’s a type of malocclusion that can lead to various oral health issues. Understanding how to diagnose and fix an underbite is crucial for both dental professionals and patients.

Key Facts

Underbite is a type of malocclusion where the lower teeth sit in front of the upper teeth when the jaw is closed

It affects around 5-10% of the world’s population

Underbites can range from mild to severe, affecting the appearance, oral health, and functioning of the jaw

Genetic factors are a common cause, but habits such as thumb-sucking or prolonged use of a pacifier can contribute to the development of an underbite in children

There are several treatment options including braces, surgery, and devices that help to realign the jaw

Treatment is crucial not only for aesthetic reasons but also to prevent complications such as difficulty in chewing, speaking, and increased risk of cavities

What is an Underbite?

An underbite, clinically referred to as Class III malocclusion or prognathism, is a dental condition characterized by the lower jaw extending out (protruding beyond the upper front teeth), causing the lower front teeth to sit in front of the upper front teeth. This leads to the unique appearance of the chin being more prominent. This is opposite to the normal alignment where the upper jaw slightly overlap the lower teeth. The underbite can be due to the misalignment of the teeth, the misalignment of the jaw, or both. It affects not just the functionality of the teeth but often also the facial appearance. An underbite can vary in severity from slight to severe, and it affects not only the alignment of the teeth but can also alter the general shape and appearance of the face.

How Common Are Underbites?

Underbites are relatively common, it is estimated that approximately 5-10% of the population has some degree of an underbite. The prevalence can vary among different ethnic groups – underbites are more common in certain ethnic groups, particularly those of Asian descent. Both children and adults can have underbites, though treatment is often easier and more effective if initiated during childhood when the jaw is still developing. Despite its prevalence, it is less common compared to overbites where the upper teeth overlap the lower teeth.

What Are The Symptoms of an Underbite?

An underbite is often identifiable by physical appearance, but it also presents various symptoms including:

Misalignment of the Teeth: The lower teeth sit in front of the upper teeth when the jaw is closed.
Visible Protrusion of the Lower Jaw: This is often the most noticeable sign of an underbite.
Difficulty Chewing and Biting: It may be challenging to chew and bite food effectively.
Altered Facial Appearance: The shape of the face might be affected, sometimes resulting in a bulldog appearance.
Speech Issues: The misalignment may affect the ability to pronounce certain sounds and words.
Tooth Wear and Decay: Due to misalignment, there can be uneven wear on the teeth, and it might be harder to clean them effectively, increasing the risk of decay.
Chronic Jaw or Muscle Pain: This is often due to the muscles straining to position the jaw properly.
Pain and Discomfort: Some people with underbites experience pain in the jaw and face, especially when chewing.
Breathing Problems: Including breathing through the mouth – some people with severe underbites may have difficulty breathing through their nose.

Recognizing these symptoms is essential for early intervention, which can reduce the likelihood of complications later in life. It is important to consult a dentist or orthodontist if you or your child displays signs of an underbite.

What Are The Complications of an Underbite?

If left untreated, an underbite can lead to various complications:

Increased Risk of Tooth Decay and Gum Disease: The abnormal positioning of the teeth can make oral hygiene more challenging, leading to an increased risk of tooth decay and gum disease.
Difficulty Chewing and Eating: Misalignment of the teeth can make it hard to chew food properly. This might lead to digestive issues as well, since digestion starts in the mouth through the mechanical breakdown of food.
Speech Impairment: An underbite can affect the ability to pronounce certain words and sounds clearly, potentially leading to speech impediments.
Temporomandibular Joint (TMJ) Disorders: An underbite can put stress on the jaw joint, potentially leading to TMJ disorders which can cause pain in the jaw, as well as headaches.
Tooth Wear: The misalignment can cause uneven wear and tear on the teeth, which over time can lead to the weakening of the teeth.
Altered Facial Appearance: An underbite can affect the shape and appearance of the face, often leading to decreased self-esteem or confidence.
Breathing Issues: In severe cases, an underbite can lead to obstructive sleep apnea, a condition where breathing is briefly and repeatedly interrupted during sleep.
Aesthetic Concerns and Self-esteem Issues: The appearance of an underbite might affect a person’s self-esteem and confidence.

Early intervention can often prevent or mitigate many of these complications. Various treatments, from dental braces to surgery, are available based on the severity and underlying cause of the underbite. It is important for individuals with an underbite, especially children, to be evaluated by a dentist or orthodontist for appropriate recommendations.

What Causes an Underbite?

There are several factors that can contribute to the development of an underbite:

Genetics: Often, underbites are hereditary. If parents have an underbite, their children are more likely to develop one.
Childhood Habits: Habits such as thumb sucking, prolonged bottle feeding, or using a pacifier beyond the age of three can affect jaw growth and contribute to the development of an underbite.
Tumors and Cysts: Abnormal growths in the jaw can cause an underbite by affecting the alignment of the jaw.
Jaw Developmental Factors: In some cases, an underbite develops due to a mismatch in the development of the upper and lower jaw. One jaw might grow too much or the other might not grow enough.
Tooth Misalignment: In certain cases, an underbite may be caused by the misalignment of the teeth rather than the jaw.
Injuries: Trauma to the jaw area, especially during childhood, can affect the way the jaw develops and lead to an underbite.
Cleft Palate or Other Birth Defects: Conditions such as cleft palate can contribute to the development of an underbite.

Diagnosis: How is an Underbite Diagnosed?

Diagnosing an underbite typically involves a combination of physical examination and imaging tests:
This examination usually includes:

Dental Examination: A dentist or orthodontist will examine the teeth and jaw. The bite will be assessed to see how the teeth align when the jaws are closed.
Dental X-rays: These are used to take images of the teeth and jaw to assess the bone structure and alignment.
Impressions: Dental impressions may be taken to make a model of the teeth; this helps the dentist study the bite more closely.
Medical History: The healthcare provider will ask about any family history of underbites or related conditions, as well as any habits that could contribute to the condition.
3D Imaging: In some cases, 3D imaging might be used to create detailed images of the teeth and jaw.

After the diagnosis, a treatment plan will be discussed depending on the severity and cause of the underbite.

At What Age Should You Fix an Underbite?

Addressing an underbite as early as possible is ideal for achieving the best results.
Here’s a rough timeline:

Early Intervention (7-10 years old): Orthodontists often recommend an evaluation for children by the age of 7. If an underbite is detected early, appliances such as palate expanders or braces can be used to guide the growth of the jaw and improve alignment.
Adolescence (11-17 years old): This is a common age for correcting underbites as the jaw is still growing and more receptive to treatment. Comprehensive orthodontic treatment including braces is often employed during this period.
Adulthood (18 years and older): Though treatment is easier in children and adolescents, underbites can still be corrected in adulthood. Treatment options might be more limited, and in some cases, surgery may be required.

Underbite in Children vs Adults

Child’s Treatment: Early treatment is essential as a child’s jaw is still growing, which allows for more effective correction.
Adult’s Treatment: In adults, particularly those with a severe underbite, treatment may require surgery in addition to orthodontic methods.

Treatment: What are Treatments for Underbite Correction? Is Jaw Surgery Necessary?

To fix an underbite several treatment options are available:

Braces and Retainers: Braces and retainers can be used to move the teeth and correct mild to moderate underbites. This is especially effective in children and adolescents whose jaws are still growing.
Clear Aligners: For less severe cases, clear aligners can be used to correct an underbite without braces.
Tooth Extraction: In cases where the mouth is crowded, extracting one or more teeth can make space for the remaining teeth to be realigned.
Palate Expanders: An upper jaw expander is used in children and adolescents to guide the growth of the jaw. Palate expanders widen the upper jaw so that the upper teeth can properly overlap the lower teeth.
Reverse-Pull Face Mask: This device wraps around the head and attaches to braces to pull the upper jaw forward.
Jaw Surgery: For severe underbites or those in adults where the jaw has finished growing, orthognathic surgery may be required. This involves surgically repositioning the jaw to achieve proper alignment.
Dentofacial Orthopedics: This involves using special appliances to better align the teeth and jaw bones.

It’s important to consult a dentist or orthodontist to determine the most appropriate treatment option based on individual circumstances. Proper care and adherence to the treatment plan are essential for successful underbite correction.

How Can I Prevent an Underbite?

In many cases, underbites are due to genetic factors, making them difficult to prevent. However, addressing modifiable factors early can sometimes prevent an underbite from developing or worsening:

Early Intervention: It is essential to monitor children’s dental development closely. If there are any signs of an underbite, consulting an orthodontist at an early stage can help manage the condition more effectively.
Addressing Childhood Habits: Habits like thumb sucking or prolonged use of a pacifier should be discouraged as they can affect the development of the jaw. Encourage children to give up thumb sucking and limit pacifier use after the age of 3.
Using Protective Gear: If engaged in sports or activities that pose a risk of injury to the face, it is advisable to wear protective gear to safeguard against any trauma that could affect jaw development.
Tongue Positioning Exercises: Teach children to keep the tongue in the correct position, as pushing it against the teeth can affect jaw development.
Regular Dental Checkups: Regular dental checkups from an early age can help in detecting any signs of an underbite early on.
Healthy Diet and Nutrition: A balanced diet that supports healthy bone development can be beneficial.

It’s important to remember that not all underbites can be prevented, especially those that are hereditary. In such cases, early intervention is key for the best outcomes.

What is the Outlook for People with an Underbite?

The outlook for people with an underbite varies based on the severity of the condition and the treatment approach. With early detection and intervention, many cases can be successfully corrected. Even in cases where the underbite is diagnosed later in life, there are still effective treatment options, though they may be more invasive and take longer. However, for severe underbites or cases where treatment is not sought, the outlook may not be as favorable due to potential complications.

Do Underbites Get Worse with Age?

Underbites can get worse with age, especially if left untreated. As individuals age, the bones of the jaw solidify and the teeth can continue to shift. This can cause an underbite to become more pronounced over time. Without intervention, the misalignment can become more pronounced, leading to increased difficulties with chewing, speaking, and potential development of temporomandibular joint (TMJ) disorders.

What Happens If I Don’t Fix My Underbite?

If an underbite is not addressed, several complications can arise:

Chewing Difficulties: An underbite can make it challenging to chew food properly, which could affect digestion.
Speech Issues: An underbite can affect the way you speak, and might cause lisps or other speech impediments.
Increased Wear on Teeth: The misalignment of the teeth can cause uneven wear and tear.
Facial Changes: The shape of the face can be altered due to an underbite.
Self-Esteem and Psychological Impact: The appearance of an underbite might affect an individual’s self-esteem and confidence, and can have psychological impacts.
Gum Problems and Tooth Decay: An underbite can make it more difficult to maintain oral hygiene, which can lead to gum problems and cavities.
Jaw Pain and TMJ Disorders: Temporomandibular joint disorders, which cause pain in the jaw joint and in the muscles that control jaw movement, can develop.

Considering the potential complications, it is advisable to consult an orthodontist to discuss treatment options for an underbite. Early intervention is key to preventing the escalation of issues associated with underbites. Proper dental care, along with tailored treatment, can greatly improve the quality of life for individuals with this condition.

Caring for Yourself or Your Child with an Underbite

Here’s the answer to the question: How do I care for myself (or my child)?
Taking proper care of yourself or your child during and after underbite treatment is essential for ensuring the best outcome.
Here are steps to follow:

Maintain Good Oral Hygiene: Whether you or your child has an underbite, maintaining good oral hygiene is crucial. This includes regular brushing and flossing. You should also ensure regular dental check-ups.
Follow Dental Recommendations: If orthodontic treatment is recommended, follow through with it. This could include wearing braces, retainers, or other dental appliances as instructed.
Follow Orthodontist’s Instructions: Adhere to the orthodontist’s advice regarding braces, retainers, or other appliances.
Regular Dental Check-ups: It’s important to have regular check-ups to monitor the progress of the underbite and to make adjustments to the treatment plan as necessary.
Encourage Healthy Eating Habits: Avoid hard or sticky foods that could damage braces or other appliances. Focus on a balanced diet for overall health.
Wear Retainers as Directed: If retainers are prescribed after braces, ensure they are worn as directed to keep teeth in their new position.
Address Concerns Promptly: If there are any issues or concerns, such as pain or discomfort, discuss them with the healthcare provider without delay.
Pain Management: If you or your child is experiencing discomfort or pain due to the underbite, over-the-counter pain relievers can help. Speak with your healthcare provider for recommendations.

Questions to Ask Your Doctor

What is the severity of the underbite? Understanding the extent of the underbite can help you understand the need for treatment.
What are the treatment options? It’s important to know all available treatment options to make an informed decision.
What are the risks and benefits of each treatment option? Each treatment option has its risks and benefits. It’s important to weigh these before deciding on a treatment plan.
Will surgery be necessary? In severe cases, surgery might be recommended. Ask about the procedure, the risks, the recovery time, and the expected outcome.
How will the underbite impact dental health if left untreated? Knowing the potential consequences of not treating the underbite can help you decide whether to proceed with treatment.
How often should we have check-ups? Regular monitoring is crucial during treatment, so it’s essential to know how often you should visit the dentist.
Are there any specific oral hygiene practices we should follow? Depending on the type of treatment, there may be specific oral care guidelines to follow.
What can we do to manage discomfort or pain? If the underbite is causing discomfort, ask your healthcare provider about ways to manage this.

Remember, open communication with your healthcare provider is essential when dealing with any medical condition. Don’t hesitate to ask questions or express your concerns.

The Difference Between an Underbite and an Overbite

An underbite and an overbite are both types of malocclusions or misalignments in the way the upper and lower teeth fit together. However, they refer to different types of misalignments.

An underbite is a condition where the lower teeth and jaw protrude in front of the upper jaw when the mouth is closed. It is also known as prognathism. This condition can lead to difficulties with biting and chewing, speech issues, tooth wear, and changes in facial appearance.
An overbite, on the other hand, is a condition where the upper teeth overlap the lower teeth excessively when the mouth is closed. This is also sometimes referred to as a deep bite. Overbites can cause the chin to recede, leading to a change in facial appearance, and can also lead to problems with speech, eating, tooth wear, and may contribute to temporomandibular joint disorders.

Bottom Line

An underbite is a dental condition that involves the misalignment of the jaws, with the lower jaw protruding beyond the upper jaw. It’s important to address underbites early on, especially in children, to prevent complications such as tooth wear, jaw pain, or speech issues, and avoid the need for jaw surgery. There are several treatment options available, ranging from braces and retainers to surgery in severe cases. Proper oral care and adherence to the treatment plan are crucial for a successful outcome. Consulting with an orthodontist and understanding the options and expectations is an essential step in managing underbites.

This article is complete and was published on July 10, 2023, and last updated on December 22, 2023.

Key Facts