Open bite

An open bite is a type of malocclusion in which some of the upper and lower teeth do not make contact when the mouth is closed. Most often, the gap is visible between the front teeth even though the back teeth are touching. This is called an anterior open bite. Less commonly, the front teeth may meet while some of the back teeth remain apart, which is known as a posterior open bite.

For some people, an open bite is mainly noticeable when they look at their smile. For others, it can affect everyday functions. A person with an anterior open bite may find it difficult to bite cleanly through foods such as a sandwich, pizza, or a piece of fruit because the front teeth do not meet. Some people also notice changes in chewing, swallowing, or the pronunciation of certain sounds, although these problems are not present in everyone.

An open bite can develop for different reasons and at different stages of life. In some patients, the main issue involves the position or eruption of the teeth. In others, the growth and relationship of the jaws play a larger role. Oral habits and tongue function may also influence the development or persistence of an open bite. Because these patterns can look similar from the outside but require different approaches, an orthodontic assessment is important before deciding whether treatment is needed and which option may be appropriate.

How open bite can affect daily life

The effect of an open bite depends on where the lack of tooth contact occurs and how pronounced it is. A small open bite may cause few or no functional problems, while a larger opening can make some everyday tasks more noticeable.

• Biting food: when the front teeth do not meet, biting through foods with the incisors can be difficult or may require using the side teeth instead.
• Chewing: some people may feel that chewing is less efficient because the teeth do not contact evenly.
• Speech: the position of the teeth and tongue may contribute to changes in the pronunciation of certain sounds, but an open bite does not automatically cause a speech problem.
• Swallowing and tongue position: some patients have an altered tongue position at rest or during swallowing. In other patients, the tongue may adapt to the existing space rather than being the original cause of it.
• Appearance: the visible gap between the upper and lower front teeth may affect how a person feels about their smile.

These features can occur individually or together. The appearance of the bite alone does not show whether the cause is primarily dental, functional, or related to jaw growth.

Common causes of open bite

Open bite is usually considered a multifactorial problem. This means that more than one factor may contribute to its development. Identifying the dominant pattern is important because the treatment of a mainly dental open bite may differ from the management of a significant skeletal open bite.

Dental and dentoalveolar factors

A dental or dentoalveolar open bite is primarily related to the position, inclination, or eruption of the teeth and the surrounding supporting structures rather than to a major discrepancy in the underlying jaw bones.

During childhood, prolonged thumb or finger sucking and prolonged pacifier use can influence the position of the developing front teeth and contribute to an anterior open bite. The effect depends on factors such as how often the habit occurs, how long it continues, and the stage of dental and facial development.

Tooth eruption patterns and the position of the front or back teeth can also contribute. For this reason, two patients with a similar visible gap may have quite different orthodontic findings.

Skeletal and growth-related factors

In a skeletal open bite, the relationship and vertical growth pattern of the jaws contribute more substantially to the lack of tooth contact. Facial growth, the position and rotation of the jaws, and inherited craniofacial characteristics can all influence how the upper and lower teeth meet.

This distinction becomes particularly relevant when assessing adolescents who are still growing and adults whose facial growth is largely complete. A pronounced skeletal pattern may require a different treatment strategy from an open bite caused mainly by tooth position.

Tongue position and oral function

Tongue posture and function are often evaluated in patients with an anterior open bite. A tongue that rests or moves between the front teeth may influence the forces acting on the teeth, but the relationship is not always straightforward. In some people, altered tongue position may contribute to the bite pattern. In others, the tongue may move forward because an open bite already exists and the body is adapting during swallowing or speech.

For that reason, the presence of tongue thrust or an unusual tongue position should not automatically be assumed to be the cause of an open bite. An orthodontist may assess tongue posture, swallowing, lip function, oral habits, and other functional findings as part of the overall evaluation.

If a patient also has persistent speech, swallowing, or breathing concerns, additional assessment by an appropriate professional may be recommended when clinically indicated. Orthodontic treatment should not be expected to automatically resolve unrelated speech or airway problems.

Open bite in children, adolescents, and adults

In children, an orthodontist can evaluate how the teeth and jaws are developing and whether oral habits are still present. Some bite changes during growth may evolve as habits stop and permanent teeth erupt, while other patterns benefit from closer monitoring or early orthodontic intervention. An early evaluation does not necessarily mean that treatment needs to start immediately.

In adolescents, more permanent teeth are usually present and the remaining jaw growth can be considered when planning treatment. At this stage, the orthodontist may be able to determine more clearly whether the open bite is predominantly dental, skeletal, functional, or a combination of these factors.

In adults, the same distinction remains important, but jaw growth is largely complete. Many dental open bites can be approached orthodontically, while selected adults with more pronounced skeletal discrepancies may need a broader evaluation to determine whether orthodontics alone can reasonably address the problem.

Symptoms that may appear with open bite

The most characteristic finding is simply that part of the upper and lower dentition does not meet when the person bites normally. Other features that may be present include:

• difficulty biting through food with the front teeth
• a visible space between the upper and lower front teeth when the back teeth are together
• lack of contact between some back teeth in a posterior open bite
• changes in chewing efficiency
• tongue movement between the teeth during swallowing or speech
• difficulty pronouncing certain sounds in some patients
• other orthodontic irregularities affecting tooth position or jaw relationships

None of these additional findings alone identifies the cause. The combination of the bite pattern, age, facial growth, tooth position, habits, and functional findings provides more useful information than any single symptom.

When open bite needs medical or dental attention

An open bite is usually not an emergency, and many people seek an orthodontic assessment because the bite has gradually developed or because it affects eating, appearance, or oral function. A persistent open bite in a child, adolescent, or adult is reasonable to discuss with an orthodontist, particularly if it is becoming more noticeable or interfering with biting or chewing.

More prompt dental or medical assessment is appropriate when the way the teeth meet changes suddenly after an injury to the face or jaw, especially if there is significant pain, swelling, a broken or displaced tooth, difficulty moving or closing the jaw, or a new bite change that was not present before the trauma.

Persistent breathing, swallowing, or speech difficulties also deserve their own assessment rather than being attributed to the open bite without further evaluation.

How open bite is usually diagnosed

Orthodontic examination

The first step is usually an orthodontic examination. The orthodontist evaluates which teeth are not making contact, the size and location of the opening, tooth alignment, the relationship between the upper and lower dental arches, and the facial and jaw pattern.

The history is also relevant. For a child or adolescent, the orthodontist may ask about thumb or finger sucking, pacifier use, previous orthodontic treatment, growth, and when the bite problem was first noticed. For adults, previous orthodontic treatment and any history of the bite reopening after treatment can also be important.

Functional assessment and imaging

The examination may include an assessment of tongue posture, swallowing, lip function, chewing, and other oral habits when these are relevant to the individual case. If speech or breathing concerns are present, the orthodontist may recommend additional evaluation rather than assuming that they are caused solely by the bite.

Photographs, digital dental scans, or dental impressions may be used to document how the teeth meet. X-rays are requested when they provide information needed for diagnosis or treatment planning. Depending on the case, imaging may help assess tooth position, developing teeth, jaw relationships, and the underlying skeletal growth pattern. Not every patient requires the same type of imaging.

What the next step may involve

The next step depends less on the visible gap itself and more on why the teeth are not meeting. Age, remaining growth, the position of the teeth, the relationship of the jaws, oral habits, functional findings, previous treatment, and the severity of the open bite can all change the treatment plan.

For a growing child, the orthodontist may recommend observation, addressing a persistent oral habit, functional guidance, or orthodontic treatment when there is a clear indication. The goal is to work with the child's stage of dental and jaw development rather than assume that every open bite requires immediate appliance therapy.

For adolescents and adults with an appropriate dental or dentoalveolar pattern, treatment may involve fixed braces or clear aligners. Different orthodontic mechanics can be used to change the position of the front teeth, back teeth, or both, depending on what is producing the open bite.

Patients considering treatment can read more about open bite correction, but the suitability of a particular appliance can only be determined after an individual orthodontic assessment.

When functional findings are significant, cooperation with other professionals may be useful. Depending on the findings, this can include assessment of speech and swallowing function or evaluation of persistent nasal or airway symptoms. Such collaboration is based on the individual patient's needs and is not required for every open bite.

In selected adults with a substantial skeletal discrepancy, an orthodontic assessment may show that conventional tooth movement alone cannot fully address the jaw relationship. In such cases, combined orthodontic and orthognathic surgical treatment may be discussed as one possible pathway. This is reserved for appropriately selected skeletal cases and requires separate specialist assessment.

Retention is an important part of planning after active orthodontic treatment. Open bite can have a risk of recurrence, particularly when growth, oral habits, tongue posture, skeletal relationships, or other contributing factors remain relevant. Retainers and follow-up are therefore used according to the individual treatment plan. No orthodontic treatment can guarantee that an open bite will remain permanently closed without considering long-term stability and retention.

What to prepare before a medical appointment

If you are requesting an orthodontic assessment for an open bite, a few details can make the first evaluation more useful. Consider preparing:

• the age of the patient and when the open bite was first noticed
• whether the gap is mainly between the front teeth or whether some back teeth also fail to meet
• whether the bite appears to be changing over time
• any difficulty biting foods such as sandwiches or other foods that normally require the front teeth
• any chewing, swallowing, speech, or breathing concerns
• current or previous thumb, finger, or pacifier habits in children
• previous orthodontic treatment and whether the bite changed again after treatment
• existing dental X-rays, photographs, scans, orthodontic reports, or treatment records if available
• what you would most like the orthodontist to clarify, such as whether treatment is needed, whether growth is involved, or whether braces or aligners may be suitable

If you are looking for assessment or treatment of an open bite in Zagreb, you can send ZagrebMed a short description of the bite problem together with any existing orthodontic or dental records. ZagrebMed can help connect your inquiry with an appropriate orthodontic examination or treatment pathway in Zagreb.