Understanding Deep Bite: Causes, Risks, and Aligner Treatments

A deep bite is more than a cosmetic issue. Learn what causes it, the health risks if left untreated, how clear aligners can help correct it, and what to expect from treatment in the UK.

A deep bite is one of the most common bite problems seen in orthodontic practice, yet many people live with one for years without realising it could be causing damage. If your upper front teeth overlap your lower front teeth significantly when you bite down, you may have a deep bite. Left unaddressed, it can lead to worn enamel, gum damage, jaw discomfort, and even chipped teeth. The good news is that deep bite correction with clear aligners is now a well-established treatment option for many adults in the UK. This guide explains what a deep bite is, what causes it, when it needs treatment, and how modern aligner technology can help.

📌 TL;DR

A deep bite occurs when the upper front teeth excessively overlap the lower front teeth vertically. It can cause enamel wear, gum damage, and jaw discomfort. Clear aligners can correct many deep bite cases using techniques like bite ramps, intrusion movements, and attachments. Treatment typically takes 6-18 months depending on severity. A clinical assessment is essential to determine suitability, as severe skeletal deep bites may require alternative approaches.

Who This Guide Is For

This article is for UK adults who suspect they have a deep bite and want to understand their options. It may be relevant if you:

Have been told by a dentist that you have a deep bite or excessive overbite
Notice that your upper front teeth cover most or all of your lower teeth when you smile or bite together
Experience worn, chipped, or sensitive front teeth and want to understand if your bite is the cause
Are considering invisible braces and want to know if they can fix a deep bite
Had braces as a teenager but your bite has relapsed
Want an honest, balanced explanation before booking a consultation

⚠️ When to Seek a Clinician Assessment First

If you experience jaw pain, clicking or locking of the jaw joint, frequent headaches, difficulty chewing, or if your lower teeth are biting into the gum behind your upper teeth, you should see a dental professional promptly. These symptoms may indicate a significant bite problem that needs clinical evaluation before any treatment decisions are made.

Key Definitions in Plain English

Deep Bite

A deep bite (sometimes called a deep overbite) is a vertical bite problem where the upper front teeth overlap the lower front teeth by more than the normal amount. A normal overlap is approximately 2-3 mm, or about 20-30% of the lower tooth height. When the overlap exceeds this significantly - covering more than half or even all of the lower front teeth - it is classified as a deep bite.

Overbite

Overbite refers to the vertical overlap of the upper front teeth over the lower front teeth. Everyone has some degree of overbite - it is a normal part of how teeth fit together. The term "deep bite" is used when the overbite is excessive. You can read more about how overbite is assessed and treated on our overbite conditions page.

Overjet

Overjet is different from overbite, though the terms are often confused. Overjet refers to the horizontal distance between the upper and lower front teeth - how far forward the upper teeth sit relative to the lower teeth. A deep bite is a vertical problem; an overjet is a horizontal one. Many patients have both.

Other Terms You May Encounter

Bite ramps: Small raised platforms built into the inside surface of upper aligners, behind the front teeth. When you bite together, the lower front teeth contact these ramps, which helps open the bite by preventing the back teeth from over-erupting and encouraging intrusion of the front teeth.
Intrusion: An orthodontic movement that pushes a tooth upward (in the upper jaw) or downward (in the lower jaw) into the bone. Used to reduce the vertical overlap in deep bite cases.
Extrusion: The opposite of intrusion - moving a tooth outward from the bone. Sometimes the back teeth need slight extrusion to help open the bite.
Attachments: Small tooth-coloured composite bumps bonded to specific teeth during aligner treatment. They help the trays grip teeth for more controlled movements, and are particularly important in deep bite correction.
IPR (Interproximal Reduction): Carefully removing tiny amounts of enamel between teeth to create space for alignment. A routine part of many aligner treatments.
Refinements: Additional sets of aligner trays produced after the initial series to fine-tune the result. Deep bite cases often require at least one round of refinements.
Retainers: Custom-made devices worn after treatment to hold teeth in their new positions.
Tracking: How well your teeth are following the planned movement sequence during aligner treatment.
3D scan: A digital impression of your teeth using an intraoral scanner, forming the basis for treatment planning.

What Causes a Deep Bite?

A deep bite can develop for several reasons, and understanding the cause helps determine the most appropriate treatment approach:

Genetics and Jaw Structure

The most common cause. If you have inherited a smaller lower jaw relative to your upper jaw, or if the angle of your jaw growth favours a deep bite, you may develop an excessive vertical overlap naturally as your teeth erupt. This skeletal component is important because it determines how much can be achieved with tooth movement alone versus whether jaw-level intervention is needed.

Tooth Position and Eruption

Over-erupted front teeth: The upper or lower front teeth may have erupted too far, creating excessive vertical overlap
Under-erupted back teeth: If the back teeth (premolars and molars) have not erupted fully or have been lost, the bite can deepen as there is less posterior support to maintain the correct vertical dimension
Tooth size discrepancy: If the front teeth are proportionally larger than average, they may overlap more

Tooth Loss

Missing back teeth is a significant and often overlooked cause of deep bite in adults. When molars or premolars are lost and not replaced, the bite can collapse vertically - the front teeth come together more, deepening the overbite over time. This is one reason why replacing missing teeth promptly is important for long-term bite stability.

Habits and Wear

Bruxism (teeth grinding): Chronic grinding can wear down the biting surfaces of the back teeth, reducing their height and allowing the bite to deepen
Nail biting or object chewing: Habitual biting on hard objects can affect tooth position over time
Tongue thrust: An abnormal swallowing pattern where the tongue pushes against the front teeth can influence bite development

Orthodontic Relapse

If you had orthodontic treatment as a teenager that corrected a deep bite but did not wear retainers consistently, the bite can relapse - gradually returning towards its original deep position over the years.

💡 Why This Matters for Treatment

The cause of your deep bite determines what can be achieved with aligners. A deep bite caused primarily by tooth position (dental deep bite) is generally more treatable with clear aligners than one caused by jaw structure (skeletal deep bite). This is why a thorough clinical assessment - including X-rays - is essential before treatment begins.

Deep Bite Explained: Overbite vs Deep Bite

These terms cause a great deal of confusion, so here is a clear breakdown:

Term	What It Means	When It Is a Problem
Normal overbite	Upper front teeth overlap the lower by 2-3 mm (20-30%)	It is not - this is healthy and normal
Increased overbite	Overlap of approximately 4-6 mm (40-60%)	May cause accelerated wear; worth monitoring
Deep bite	Overlap exceeding 50-60%, often covering the lower teeth almost entirely	Can cause enamel wear, gum damage, and jaw issues
Traumatic deep bite	The lower front teeth bite into the gum tissue behind the upper teeth	Actively damaging tissue; treatment usually recommended

Health Risks of an Untreated Deep Bite

A deep bite is not just a cosmetic concern. Left untreated, it can lead to:

Accelerated enamel wear: The upper and lower front teeth grind against each other more intensely, wearing down the enamel faster than normal. Over decades, this can lead to thin, translucent, or chipped front teeth
Gum damage (palatal trauma): In severe cases, the lower front teeth bite into the gum tissue on the roof of the mouth behind the upper teeth, causing chronic irritation, ulceration, and tissue damage
Jaw joint problems (TMD): A deep bite can alter how the jaw joint (temporomandibular joint) functions, potentially contributing to jaw pain, clicking, locking, or headaches
Tooth fractures: The concentrated force on the front teeth increases the risk of chips and fractures, particularly as enamel thins with wear
Difficulty with dental work: A deep bite can complicate restorative dental work (crowns, veneers) on the front teeth because the opposing teeth exert excessive force on the restorations
Aesthetic concerns: A deep bite can make the lower face appear shorter, the chin more prominent, and the smile appear "gummy" or show less of the lower teeth

What Clear Aligners Can Do (and What They Cannot)

What Aligners May Help With

Dental deep bites: When the deep bite is caused primarily by tooth position rather than jaw structure, clear aligners can be highly effective. They can intrude over-erupted front teeth, level the arch, and adjust the bite relationship.
Bite ramp correction: Modern aligner systems include built-in bite ramps that actively help open the bite during treatment - a significant advancement in deep bite correction with aligners.
Combined alignment and bite correction: If you have a deep bite alongside crowding, spacing, or rotations, aligners can address both the alignment and the bite simultaneously.
Mild to moderate deep bites: Cases where the overbite is 4-8 mm are generally within the treatable range for clear aligners, depending on the specific movements required.

What Aligners Cannot Do

Correct skeletal deep bites: If the deep bite is primarily caused by the jaw bones being positioned incorrectly relative to each other, aligners alone cannot change the jaw structure. Severe skeletal cases may require orthognathic (jaw) surgery.
Achieve large intrusion movements: Aligners can predictably intrude teeth by approximately 1-3 mm. If significantly more intrusion is needed, fixed braces with additional mechanics (such as temporary anchorage devices) may be more effective.
Replace missing teeth: If the deep bite has developed because of missing back teeth, the missing teeth need to be replaced (with implants, bridges, or dentures) as part of the overall treatment plan. Aligners alone cannot compensate for lost vertical support.
Guarantee prevention of relapse: Deep bites have a natural tendency to relapse. Lifelong retention is essential, and even with retainers, some degree of settling may occur over time.

Step-by-Step: How Treatment Typically Works

If you have a deep bite and your clinician determines you are a suitable candidate for clear aligners, here is what the process typically looks like:

1. Comprehensive Assessment

A thorough in-person examination including a 3D scan of your teeth, X-rays (panoramic and possibly lateral cephalometric), clinical photographs, and assessment of your bite, jaw joints, and gum health. The clinician measures the depth of your overbite and determines whether the cause is dental, skeletal, or a combination.

2. Treatment Planning

Using the 3D scan data, a digital treatment plan is created showing the proposed tooth movements from start to finish. For deep bite cases, this plan will include specific strategies: bite ramps, intrusion of the front teeth, possible extrusion of the back teeth, and attachment placement. You will typically be shown a simulation of the expected outcome before agreeing to proceed.

3. Attachment Bonding and IPR

At the start of treatment, attachments are bonded to specific teeth. Deep bite cases typically require more attachments than simple alignment cases, as the aligner needs additional grip to achieve intrusion and bite correction. IPR (gentle enamel reshaping between teeth) may also be performed if space is needed for alignment.

4. Active Treatment

You wear your aligners for approximately 22 hours per day, removing them only for eating, drinking (anything other than water), and oral hygiene. Trays are changed every 1-2 weeks. The bite ramps built into the upper aligners work passively as you bite together throughout the day, gradually encouraging the bite to open.

5. Monitoring and Adjustments

Regular check-up appointments (typically every 6-8 weeks) allow your clinician to assess tracking, check attachment integrity, monitor bite changes, and make adjustments to the plan if needed. Deep bite correction can sometimes progress unevenly, so clinical oversight is particularly important.

6. Refinements

Deep bite cases frequently need one or more rounds of refinements. After the initial aligner series, the clinician re-scans your teeth and orders additional trays to fine-tune the bite and alignment. This is a normal part of treatment, not a sign of failure. Learn more about the refinements process.

7. Retention

After active treatment, you transition to retainers. For deep bite patients, retention is especially critical because deep bites have a strong tendency to relapse. Your clinician will advise on the appropriate retention protocol - typically a combination of fixed retainers (bonded wires behind the front teeth) and removable retainers worn at night.

Suitability Checklist

Not every deep bite can be corrected with clear aligners. Here is a general guide - though only a clinical assessment can determine suitability for your specific case:

Scenario	Likely Suitable?	Notes
Mild deep bite (4-5 mm overbite)	✅	Usually very responsive to aligner treatment with bite ramps
Moderate deep bite (5-7 mm overbite)	✅ (with caveats)	Achievable in many cases; may need more trays, attachments, and refinements
Severe deep bite (8+ mm overbite)	⚠️	May require fixed braces, TADs, or a combination approach
Skeletal deep bite (jaw-related)	⚠️	Aligners can camouflage mild skeletal issues; severe cases may need surgery
Deep bite with crowding	✅	Common combination; aligners can address both simultaneously
Deep bite with missing back teeth	⚠️	Missing teeth need replacing as part of treatment; multidisciplinary approach
Deep bite with active gum disease	❌	Gum health must be stabilised before orthodontic treatment begins

Aligner Strategies: How Deep Bite Correction Works

Deep bite correction with clear aligners relies on several specific techniques. Understanding these helps you appreciate why treatment planning for deep bites is more complex than simple alignment cases:

Bite Ramps

What they are: Raised platforms built into the palatal (tongue-side) surface of the upper aligner, positioned behind the upper front teeth. When you bite together, your lower front teeth contact these ramps instead of the aligner surface.

How they work: Bite ramps serve two functions. First, they disocclude (separate) the back teeth slightly, which can allow the back teeth to erupt a small amount, adding vertical height at the back of the mouth. Second, the contact force on the ramps can help intrude the lower front teeth slightly. Both effects contribute to opening the bite.

Patient experience: Bite ramps may feel unusual initially - you will feel a raised area when you bite together. Most patients adjust within a few days. They can occasionally affect speech briefly.

Intrusion of Front Teeth

Intrusion involves pushing the upper front teeth, the lower front teeth, or both upward into the bone to reduce the vertical overlap. This is one of the most challenging orthodontic movements to achieve with any appliance, but modern aligner systems with well-placed attachments can accomplish 1-3 mm of intrusion predictably. Larger intrusion amounts become progressively less reliable with aligners alone.

Extrusion of Back Teeth

In some cases, the treatment plan may include slight extrusion (lengthening) of the premolars or molars to increase the vertical height at the back of the mouth, effectively opening the bite. This approach is sometimes used in combination with front tooth intrusion for optimal results.

Attachments for Deep Bite Cases

Deep bite correction typically requires more attachments than simple alignment cases. Specific attachment shapes and placements are used to achieve intrusion, control torque (the angle of the tooth root relative to the crown), and ensure predictable bite changes. Without attachments, the aligner trays cannot generate the forces needed for reliable deep bite correction.

Elastics (Rubber Bands)

In some deep bite cases, your clinician may prescribe small rubber bands (elastics) that connect between hooks on the upper and lower aligners. These provide additional forces that the aligners alone cannot generate, particularly for correcting the relationship between the upper and lower arches. Not all deep bite cases require elastics, but they can significantly improve outcomes in suitable cases.

In Practice: Combination Approach

Most deep bite treatment plans use a combination of these strategies. For example: bite ramps to help open the bite passively, attachments on the front teeth to enable intrusion, and careful levelling of the arch to create a more even bite. The specific combination depends on your individual case, which is why standardised "one-size-fits-all" treatment plans are not appropriate for deep bite correction.

Risks, Side Effects, and Limitations

A balanced view of what can go wrong or what to expect:

Risks and Side Effects

Root resorption: All orthodontic tooth movement carries a small risk of root shortening (resorption). Intrusion movements, which are central to deep bite correction, may carry a slightly higher risk. Your clinician should monitor this with X-rays during treatment.
Gum recession: Moving teeth - particularly intrusion and proclination movements - can occasionally contribute to gum recession, especially if the bone is thin. Pre-existing gum recession increases this risk.
Relapse tendency: Deep bites are among the most relapse-prone orthodontic corrections. Even with excellent retention, some deepening of the bite may occur over years. Lifelong retainer wear is strongly recommended.
Discomfort: Some discomfort is normal, particularly when starting a new tray. Deep bite correction may produce additional jaw soreness as the bite relationship changes. This is typically mild and temporary.
Speech changes: Bite ramps can temporarily affect speech, particularly the "s" and "th" sounds. Most patients adapt within days to a week.
Treatment may take longer than expected: Deep bite correction is less predictable than simple alignment. Additional refinement rounds are common, which can extend the overall timeline.

Limitations

Aligners require consistent wear of approximately 22 hours per day to be effective
Not all deep bite cases are suitable for aligner treatment; some require fixed braces or surgery
The amount of intrusion achievable with aligners (typically 1-3 mm) may not be sufficient for severe cases
Oral hygiene must be maintained carefully throughout treatment
Results depend on compliance and individual biology; no guarantees can be made about specific outcomes

How Long Treatment May Take

Treatment duration depends primarily on the severity of the deep bite and any accompanying alignment issues:

Case Complexity	Typical Duration	Key Factors
Mild deep bite with minor alignment issues	6-9 months	Bite ramps and minimal intrusion needed; fewer trays
Moderate deep bite with crowding	9-15 months	Significant intrusion needed; multiple attachment types; likely refinements
Complex deep bite case	15-24+ months	Combination of bite correction, alignment, and possibly elastics; multiple refinement rounds

What changes timelines: Severity of the deep bite, amount of intrusion required, whether alignment issues coexist, wear-time compliance, number of refinement rounds needed, and individual biological response. Your clinician will provide a personalised estimate after your assessment.

Costs in the UK

Deep bite correction with clear aligners typically falls within the moderate to complex treatment pricing, as it involves more clinical planning, more trays, and more monitoring than simple alignment cases.

What Drives the Price

Case complexity (mild vs moderate vs complex deep bite)
Number of aligner trays required (deep bite cases typically need more)
Whether refinements are included or charged separately
Retainer costs (essential for deep bite cases; some packages include them)
Whether additional diagnostics are needed (cephalometric X-rays for skeletal assessment)
Provider location and clinical expertise

You can review our pricing and what is included for a transparent breakdown. We always recommend asking for a detailed written cost breakdown before committing, and checking whether refinements, retainers, and monitoring appointments are included in the quoted price.

How to Keep Results: Retention and Aftercare

Retention after deep bite correction is not optional - it is essential. Deep bites are among the most relapse-prone orthodontic conditions, meaning your teeth will have a strong tendency to return towards their original position if retention is inadequate.

Retention Options

Fixed retainers: Thin wires bonded behind the upper and lower front teeth. These provide continuous retention and are typically recommended for deep bite patients on both arches. They require regular cleaning and occasional maintenance.
Removable retainers: Custom-made clear trays (similar to aligners) worn at night. These can help maintain the bite correction as well as tooth alignment. Your clinician will advise on how long to wear them - many recommend indefinite nightly wear for deep bite cases.
Combined approach: Most clinicians recommend both fixed and removable retainers for deep bite patients for maximum stability.

Aftercare Tips

Wear your retainers exactly as directed - skipping nights can allow the bite to begin relapsing
Attend regular dental check-ups so your clinician can monitor for signs of relapse or bite changes
If you grind your teeth, discuss a night guard with your clinician - grinding can accelerate relapse
Report any changes you notice: if your retainer stops fitting properly or your bite feels different, contact your provider promptly
Maintain excellent oral hygiene around fixed retainers using interdental brushes or floss threaders
Replace removable retainers when they become worn, cracked, or discoloured

Frequently Asked Questions

Is a deep bite the same as an overbite?

A deep bite is a type of overbite - specifically, an excessive one. Everyone has some degree of overbite (vertical overlap of the front teeth), and a small amount is normal and healthy. A deep bite means the overbite is significantly greater than the normal range, typically covering more than half of the lower front teeth.

Can clear aligners actually fix a deep bite?

Yes, clear aligners can correct many deep bite cases, particularly those caused by tooth position rather than jaw structure. Modern aligner systems use bite ramps, attachments, and intrusion mechanics specifically designed for deep bite correction. However, severe or skeletal deep bites may require fixed braces, surgery, or a combination approach.

How do bite ramps work?

Bite ramps are raised platforms built into the upper aligner behind the front teeth. When you bite together, your lower front teeth contact these ramps, which slightly separates the back teeth and helps open the bite over time. They work passively throughout the day as you wear your aligners.

Will fixing my deep bite change how my face looks?

It can, subtly. Correcting a deep bite may slightly increase the lower face height, which can make the facial proportions appear more balanced. The chin may appear less prominent relative to the rest of the face. These changes are usually subtle and positive, but they depend on the severity of the original deep bite and the specific movements performed.

How long does deep bite correction take with aligners?

Typically 6-18 months depending on severity, with additional time for refinements. Mild cases may resolve in as little as 6 months; complex cases with significant bite correction can take 18 months or longer. Your clinician will provide a personalised estimate after assessment.

Is deep bite correction painful?

Most patients experience some discomfort, particularly when starting a new tray. This is typically described as pressure or tightness rather than pain, and usually subsides within a few days. Bite ramps may cause additional jaw awareness initially. Over-the-counter pain relief is usually sufficient if needed. If you experience significant pain, contact your clinician.

Can a deep bite come back after treatment?

Yes - deep bites have a strong tendency to relapse. This is why lifelong retention is strongly recommended. Even with retainers, some minor deepening of the bite may occur over years. Consistent retainer wear is the best protection against significant relapse.

Do I need a special type of aligner for deep bite correction?

Not a different product, but a more complex treatment plan. Deep bite cases require specific features within the aligner design - bite ramps, strategically placed attachments, and carefully planned intrusion movements. This is why the clinical planning stage is so important, and why deep bite cases should be managed by experienced providers.

Can I eat normally during deep bite treatment?

Yes. Because aligners are removable, you take them out to eat and can eat whatever you like. You should brush your teeth before reinserting the aligners. The main dietary consideration is timing - with approximately 22 hours of recommended daily wear, you need to plan your meals and snacking efficiently.

What happens if I do not treat my deep bite?

A deep bite may remain stable for years or may gradually worsen. The main risks of leaving a significant deep bite untreated include accelerated enamel wear on the front teeth, potential gum damage behind the upper teeth, increased risk of tooth fractures, and possible jaw joint problems. However, not every deep bite needs treatment - mild cases without symptoms may simply need monitoring.

Is deep bite correction covered by the NHS?

NHS orthodontic treatment for adults is very limited in the UK and is generally only available in cases of severe functional impairment. Most deep bite correction for adults is provided privately. NHS dental examinations can identify a deep bite and refer you for specialist assessment if appropriate.

📚 References and Further Reading

Proffit WR, Fields HW, Sarver DM — Contemporary Orthodontics, 6th edition (2019)
Kravitz ND, et al. — How well does Invisalign work? A prospective clinical study evaluating the efficacy of tooth movement with Invisalign, American Journal of Orthodontics and Dentofacial Orthopedics (2009)
Khosravi R, et al. — Management of overbite with the Invisalign appliance, American Journal of Orthodontics and Dentofacial Orthopedics (2017)
NHS — Orthodontics Overview
British Orthodontic Society — Patient Information
GDC — Guidance on Advertising

Concerned About Your Deep Bite? Let Us Take a Look

Book a consultation and we will assess your bite, explain whether clear aligners are suitable for your case, and walk you through the treatment options. No obligation to proceed.

Book Your Assessment

Disclaimer: This article is for general information only and does not constitute dental or medical advice. Treatment needs, timelines, and costs vary by individual case. All cost figures are approximate UK ranges for reference and are not quotations. Whether treatment is suitable and which approach is appropriate can only be determined through an in-person clinical assessment by a GDC-registered dental professional.