Underbite vs Overbite: Key Causes & Treatment Options

Underbites and overbites, clinically referred to as underjet and overjet, are two of the most common jaw misalignment issues, also known as malocclusions. While they might seem similar, these conditions involve different jaw positions and can affect everything from chewing to facial appearance.

An underbite occurs when the lower jaw extends forward past the upper jaw. An overbite, by contrast, happens when the upper teeth overlap the lower ones excessively.

Both conditions can lead to discomfort, speech issues, and long-term oral health problems if left untreated. Thankfully, a range of treatment options, from clear aligners to corrective surgery, can help restore a healthy, functional bite.

At Burnaby Dentist & Orthodontist, bite concerns such as underbite and overbite are addressed through teeth straightening options offered via Invisalign® aligner therapy only, supported by digital assessment and treatment planning. Early evaluation can help determine whether orthodontic treatment is appropriate and when intervention may be most effective.

In this guide, you’ll learn how to tell the difference, what causes each type of malocclusion, and how early treatment can help you or your child avoid complications later on.

What is an underbite?

An underbite is a type of dental misalignment where the lower jaw extends forward, causing the lower teeth to sit in front of the upper teeth when the mouth is closed. This condition is classified as a Class III malocclusion and can range from mild to severe.

Visually, underbites often result in a prominent chin and a forward-set lower jaw, which may affect facial symmetry.
Functionally, they can interfere with chewing, speaking, and jaw comfort.

Common Underbite Risk Factors

Key contributors that may increase the likelihood of developing an underbite include:

• Genetics: Inherited jaw shape, size, or skeletal growth patterns
• Childhood Habits: Prolonged thumb-sucking, pacifier use, or mouth breathing
• Jaw Growth Imbalance: Lower jaw developing faster than the upper jaw
• Early Jaw Injury: Trauma during growth that affects natural alignment

At Burnaby Dentist & Orthodontist, underbite concerns are evaluated using digital 3D scans and comprehensive orthodontic assessments. This information helps determine whether teeth straightening options provided through Invisalign® aligner therapy are appropriate, particularly when issues are identified early and can be managed before becoming more complex.

Symptoms of an Underbite

• Lower teeth are visible in front of the upper teeth when the mouth is closed
• Difficulty chewing or biting into food
• Speech problems, such as lisps or unclear pronunciation
• Jaw discomfort or clicking during movement
• Frequent tension headaches or jaw pain
• Uneven or excessive wear on teeth

How Underbites Affect Everyday Life

Underbites can affect both function and appearance. Some people find it harder to chew efficiently, notice jaw tension, or feel self-conscious about their facial profile. Over time, untreated underbites may contribute to increased tooth wear, jaw strain, and ongoing discomfort.

At Burnaby Dentist & Orthodontist, digital bite analysis and 3D imaging are used to assess functional concerns. When orthodontic treatment is appropriate, Invisalign® in Burnaby is used as the clinic’s teeth straightening option to support improved comfort, bite function, and overall balance.

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What is an overbite?

An overbite is a dental condition where the upper teeth overlap the lower teeth vertically more than what’s considered ideal.

While a slight overbite is normal, an excessive overlap, known as a Class II malocclusion, can affect your bite, facial balance, and long-term dental health.

In more pronounced cases, the upper front teeth may protrude significantly, sometimes referred to as “buck teeth.” This can create both functional and aesthetic concerns.

Tip: Overbites are commonly identified in children, particularly when early habits such as thumb sucking are present. Early assessment helps determine whether monitoring or orthodontic intervention may be appropriate.

Common Causes of an Overbite

Genetics are a leading factor. If a parent has a deep bite or a jaw imbalance, their child may inherit a similar skeletal pattern.

A jaw size mismatch—when the upper jaw is larger or the lower jaw is smaller—can lead to excessive vertical overlap between the front teeth.

Childhood habits, such as extended thumb sucking, pacifier use, or bottle feeding, may push the upper teeth forward or interfere with jaw growth, increasing the risk of an overbite.

In some cases, teeth misalignment rather than jaw position is the culprit. Crowded or unevenly spaced teeth may shift forward or backward, causing the front teeth to overextend.

Symptoms of an Overbite

• Upper teeth noticeably overlap the lower front teeth
• Difficulty biting into foods like apples or sandwiches
• Uneven or premature wear on lower teeth
• Speech issues, including lisps or unclear pronunciation
• Jaw discomfort or clicking
• Changes in facial structure or chin profile

Key Differences Between Underbites and Overbites

Although many people confuse overbite vs underbite, these two types of malocclusion involve opposite jaw movements and different underlying causes.

An underbite happens when the lower jaw juts forward, pushing the bottom teeth in front of the upper ones. In contrast, an overbite occurs when the upper front teeth extend too far over the lower teeth, often covering them vertically.

Each condition has its own causes, symptoms, and treatment approaches. Understanding these differences helps you and your dentist choose the best care plan.

Treatment Options for Underbites and Overbites

Across orthodontics, underbites and overbites can be treated in different ways depending on age and severity. These approaches may include braces, aligner‑based treatment, or jaw correction in more complex skeletal cases.

At Burnaby Dentist & Orthodontist, bite correction is provided exclusively through Invisalign® aligner therapy, supported by digital assessment and treatment planning. We follow Canadian orthodontic guidelines recommending early evaluation around age 7.

This approach allows our team to track jaw growth and spot potential issues before they require advanced intervention. Using dental technology in Burnaby, including digital 3D scans and growth analysis tools, assessments help determine whether teeth straightening options provided through Invisalign® aligner therapy are appropriate as part of an individualized care plan.

Early Intervention in Children

Early orthodontic care can help reduce the risk of more complex issues later in life. Because children’s jaws are still developing, this stage allows clinicians to monitor growth patterns and identify bite concerns early.

In orthodontics more broadly, early intervention may include growth‑guidance appliances or other interceptive tools.

At our Burnaby clinic, early evaluations focus on monitoring growth and determining whether Invisalign®‑based treatment may be appropriate at a later stage.

Braces and Clear Aligners in Orthodontic Care (Industry Overview)

For teens and adults, orthodontic care across the field commonly includes braces or clear aligners to address bite concerns, depending on complexity and growth factors.

Braces

Traditional or ceramic braces are commonly used in orthodontics to apply controlled pressure and guide tooth movement, particularly in complex or skeletal alignment cases.

These systems are referenced here for educational comparison only and are not offered at Burnaby Dentist & Orthodontist.

Clear Aligners (Invisalign®)

Clear aligners such as Invisalign® in Burnaby are commonly used for mild to moderate bite concerns. This approach is removable and planned digitally to support controlled tooth movement.

At Burnaby Dentist & Orthodontist, Invisalign® aligner therapy is the sole orthodontic treatment offered for bite correction, with suitability determined through digital assessment and case evaluation.

Headgear

Headgear is an orthodontic appliance sometimes used in children to influence jaw growth during development, typically in combination with braces.

This approach is mentioned for general understanding and is not part of the orthodontic services provided at our clinic.

Retainers

After aligner-based treatment, retainers help maintain results. They help prevent your teeth from shifting back into their original positions. Some retainers are removable, while others are fixed behind the teeth for ongoing support.

When Jaw Surgery Becomes Necessary

In severe or skeletal cases, particularly for adults whose jawbones have finished growing, orthognathic (jaw) surgery may be recommended. This procedure repositions the upper or lower jaw to improve alignment, comfort, and appearance.

Surgery is often paired with orthodontic treatment before and after to achieve optimal, stable results. Using digital 3D imaging and surgical planning software, we ensure precise outcomes while minimizing recovery time.

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The Importance of Early Treatment

Addressing underbites and overbites early can prevent more serious dental issues down the road. Misaligned bites don’t just affect how your smile looks, they can interfere with basic functions like chewing, speaking, and even breathing.

Left untreated, these conditions may lead to:

• Speech difficulties, including lisps or trouble pronouncing certain sounds
• Jaw pain and tension, especially around the TMJ (temporomandibular joint)
• Tooth wear, enamel damage, and a higher risk of cavities or fractures
• Chewing problems, which can affect digestion and nutrition over time

Why Early Orthodontic Screenings Matter

Early orthodontic evaluation allows your dentist to identify and address developing bite problems before they become complex. Around age 7, key growth changes occur, making it the ideal time for an initial assessment.

The American Association of Orthodontists recommends that children have their first orthodontic assessment by age 7, when adult teeth and jaw patterns begin to emerge. This allows your dentist to monitor jaw growth and recommend early interventions when appropriate.1

At Burnaby Dentist & Orthodontist, we offer early screenings and digital imaging to help families plan orthodontic care with confidence and clarity.

Conclusion

Underbites and overbites are among the most common types of dental misalignment. While they may seem similar, each affects your jaw and bite in very different ways.

Understanding the key differences—and knowing what symptoms to watch for—can help you take action early. With modern orthodontic treatments in Burnaby like clear aligners, braces, or guided jaw development, it’s possible to correct most bite issues and protect your long-term oral health.

At Burnaby Dentist & Orthodontist, we tailor every treatment plan to fit your needs, using digital scans and advanced orthodontic techniques to deliver results that look great and feel natural.

If you or your child shows signs of an underbite or overbite, book a consultation with our experienced team. We offer complimentary orthodontic consultations to assess jaw alignment and discuss the most effective treatment options. Early care can prevent bigger problems—and help you or your child smile with confidence.

Book your orthodontic appointment today to explore personalized treatment options right here in Burnaby, where advanced technology meets exceptional care.