Open Bite: Symptoms, Causes, and Treatment Options

An open bite is a type of dental malocclusion in which the upper and lower teeth do not make contact when the mouth is closed. This gap between the biting surfaces can occur in the front of the mouth (anterior open bite) or on the sides (posterior open bite). Open bites can affect chewing, speech, and facial appearance, and they require orthodontic or surgical intervention to correct.

Types of Open Bite

Anterior Open Bite

An anterior open bite is the most common type and occurs when the front teeth do not overlap or touch when the back teeth are closed together. Patients can often see a visible gap between their upper and lower front teeth when biting down. This type of open bite makes it difficult to bite into foods like sandwiches, apples, or corn on the cob.

Posterior Open Bite

A posterior open bite occurs when the back teeth do not touch while the front teeth close together. This type is less common but can significantly affect chewing ability since the molars and premolars are responsible for grinding food.

Skeletal vs. Dental Open Bite

A dental open bite results from the position of the teeth themselves and can often be treated with orthodontics alone.
A skeletal open bite results from abnormal jaw growth and typically requires a combination of orthodontics and jaw surgery to correct.

Symptoms of Open Bite

The most obvious symptom is the visible gap between the upper and lower teeth when biting. Other symptoms include:

Difficulty biting and chewing: Inability to properly bite into or tear food with the front teeth
Speech difficulties: Lisping or difficulty pronouncing certain sounds, particularly “s,” “z,” and “th”
Mouth breathing: The inability to close the lips comfortably over the teeth may lead to habitual mouth breathing
TMJ discomfort: Uneven bite forces can contribute to jaw joint pain, clicking, or headaches
Lip incompetence: Difficulty closing the lips together at rest, resulting in a strained appearance when attempting to close the mouth
Tongue thrusting: The tongue may push forward into the gap during swallowing, which can perpetuate the open bite

Causes of Open Bite

Thumb Sucking and Pacifier Use

Prolonged thumb sucking, finger sucking, or pacifier use beyond the age of three to four years is one of the most common causes of anterior open bite in children. The constant pressure of the thumb or pacifier pushes the upper front teeth forward and the lower front teeth backward, creating a gap.

Tongue Thrusting

Tongue thrusting is a habitual pattern in which the tongue presses against or between the front teeth during swallowing. This repetitive force can prevent the front teeth from fully erupting into contact and can maintain or worsen an existing open bite.

Genetics and Skeletal Growth

Some people are genetically predisposed to develop an open bite due to the inherited shape and growth pattern of their jaws. A long face type (dolichofacial pattern) with a steep mandibular plane angle is associated with anterior open bites. Skeletal open bites are the most challenging to treat and the most prone to relapse.

Temporomandibular Joint Disorders

Conditions affecting the TMJ, including degenerative joint disease or condylar resorption, can alter the position of the lower jaw and contribute to the development of an open bite.

Airway Obstruction

Chronic nasal congestion, enlarged tonsils or adenoids, or allergies can force children to breathe through their mouths. Mouth breathing during growth and development can lead to altered jaw positioning and the development of an open bite.

Treatment Options

Orthodontic Treatment (Braces or Aligners)

For dental open bites, orthodontic treatment with braces or clear aligners can effectively close the gap. Treatment may involve:

Intrusion of posterior teeth: Pushing back teeth deeper into the bone to allow the jaw to rotate closed
Extrusion of anterior teeth: Bringing front teeth further into the bite to close the gap
Elastics: Vertical elastics between the upper and lower arches apply closing forces
Temporary anchorage devices (TADs): Small titanium screws placed in the bone provide stable anchoring points for intrusion mechanics

Treatment typically takes 18 to 30 months, depending on the severity of the open bite.

Habit Correction

For children with open bites caused by thumb sucking or tongue thrusting, eliminating the habit is essential before or during orthodontic treatment. Options include:

Habit-breaking appliances: Fixed devices like a tongue crib or palatal rake placed in the mouth to discourage tongue thrusting and thumb sucking
Myofunctional therapy: Exercises that retrain the tongue and facial muscles to adopt a correct swallowing pattern and resting tongue posture
Behavioral approaches: Positive reinforcement, awareness training, and gradually eliminating the habit

Orthognathic Surgery

Skeletal open bites in adults often require a combination of orthodontics and orthognathic (jaw) surgery. The surgical procedure repositions the upper jaw, lower jaw, or both to establish proper vertical and horizontal relationships. Surgery is typically performed after orthodontic alignment of the teeth, and a second phase of orthodontics follows surgery to finalize the bite.

Orthognathic surgery for open bite correction has high success rates but requires several months of recovery and post-surgical orthodontic treatment.

Early Intervention in Children

Interceptive orthodontic treatment in children ages 7 to 10 can take advantage of active jaw growth to correct developing open bites. Early treatment may include:

Growth modification appliances such as Twin Block appliances
Habit-breaking devices
Limited braces to guide erupting teeth
Referral for adenoid or tonsil evaluation if airway obstruction is contributing to the problem

Early intervention can reduce the severity of the open bite and may eliminate the need for surgery later. A Twin Block appliance or space maintainer may be part of the early treatment plan.

Stability and Relapse

Open bites have a higher relapse rate than other types of malocclusion. Factors that improve long-term stability include:

Elimination of causative habits before treatment
Proper tongue posture and swallowing pattern after treatment
Use of retainers as directed
Surgical correction when a skeletal component is present
Myofunctional therapy to maintain proper oral muscle function

At Serenity International Dental Clinic, our orthodontists thoroughly evaluate the cause and type of open bite to recommend the most effective and stable treatment approach for each patient.

Frequently Asked Questions

Can an open bite fix itself?

In young children, mild open bites caused by thumb sucking may resolve on their own once the habit stops, provided the child is still growing. However, most open bites require treatment.

Is surgery always needed for an open bite?

No. Many dental open bites can be treated successfully with orthodontics alone. Surgery is typically reserved for skeletal open bites that cannot be corrected with braces or aligners.

Can clear aligners fix an open bite?

Clear aligners can treat mild to moderate dental open bites, particularly with the use of attachments and vertical elastics. Severe or skeletal open bites generally require fixed braces or surgery.

How long does open bite treatment take?

Treatment duration depends on the cause and severity. Orthodontic treatment alone typically takes 18 to 30 months. Combined orthodontic-surgical treatment may take 24 to 36 months overall.

7 Signs Your Child Needs Orthodontic Treatment — a broader checklist of early orthodontic warning signs beyond open bite
Thumb Sucking and Tips to Help Your Child Stop — The most common cause of open bite in children and how to break the habit
Metal Braces in Hanoi — The primary orthodontic treatment for closing open bites
Invisalign Clear Aligners in Hanoi — Clear aligners for mild to moderate dental open bites
Twin Block Appliances in Hanoi — Early intervention appliances that can correct developing bite problems in children
Forsus Spring Appliance — A fixed appliance for correcting bite discrepancies during braces treatment
Types of Braces: A Complete Comparison Guide — Choose the right braces system for your open bite treatment
Orthodontic Treatment Timeline — How long open bite correction takes within the overall treatment schedule
Space Maintainers for Children — Preventive appliances that help avoid bite problems from early tooth loss
Occlusal Adjustment — Fine-tuning the bite after open bite orthodontic correction
Contact Us — Book an open bite evaluation at Picasso Dental Clinic in Hanoi