Why Proper Jaw Development Matters for Children – and What Adults Should Know About the Temporomandibular Joint

The jaws do much more than determine the alignment of the teeth and the appearance of the smile. Their development is closely related to the way a child chews, swallows, speaks, breathes, and sleeps.

An important part of this system is the temporomandibular joint (TMJ) – a small but complex joint involved every time the mouth opens and closes.

Temporomandibular disorders are less common in children than in adults, but they can still develop during childhood or adolescence. The symptoms are not always obvious. A child may not complain directly of “joint pain” but may avoid certain foods, chew only on one side, experience facial fatigue, or report headaches.

Early assessment does not necessarily mean that treatment is required. In many cases, monitoring the child’s development and providing parents with specific age-appropriate recommendations may be sufficient.

What Is the Temporomandibular Joint?

The temporomandibular joint, commonly abbreviated as TMJ, is located just in front of the ear and connects the lower jaw to the skull.

There are two temporomandibular joints – one on the left and one on the right. They must work in coordination because the lower jaw is a single bone.

Inside each joint is an articular disc, positioned between the head of the lower jaw and the temporal bone. It helps facilitate smooth movement and distribute functional forces.

When the mouth opens, the lower jaw does not simply move like a hinge. The joint head both rotates and slides forward.

When we refer to temporomandibular disorders (TMD), we are not referring only to the joint itself. The term describes a group of conditions affecting the temporomandibular joints, the masticatory muscles, and related structures.

Why Are the Jaws So Important for a Child’s Development?

During growth, the facial bones, dental arches, bite, masticatory muscles, and soft tissues develop simultaneously.

This process is influenced by both inherited characteristics and everyday functions, including:

• the position and movements of the tongue;
• swallowing patterns;
• chewing;
• nasal or mouth breathing;
• prolonged oral habits;
• the eruption and alignment of the permanent teeth;
• the individual pattern of craniofacial growth.

For this reason, an orthodontist does not assess only whether the teeth are “crooked”.

The evaluation may also include facial proportions, the development of the upper and lower jaws, the width of the dental arches, contacts between the teeth, lower-jaw movements, and the function of the orofacial muscles.

Early recognition of a developing crossbite, significant asymmetry, severe crowding, abnormal eruption direction, or functional displacement of the lower jaw allows the condition to be monitored and, when necessary, treated at the most appropriate stage of growth.

What Can Cause Temporomandibular Joint Problems in Children?

Temporomandibular disorders usually do not have a single cause.

In most cases, they result from a combination of predisposing, triggering, and perpetuating factors.

Trauma to the Chin or Lower Jaw

A fall onto the chin, a sports-related impact, a road traffic accident, or another significant injury may affect the structures of the temporomandibular joint.

In a growing child, injuries involving the mandibular condyle should be assessed carefully because, in certain cases, they may affect jaw movement and the symmetry of facial growth.

Not every minor impact causes joint damage.

A dental or medical examination is recommended when pain, swelling, limited mouth opening, a change in the bite, or visible deviation of the jaw persists after an injury.

Overloading of the Masticatory System

Prolonged daytime teeth clenching, frequent chewing gum, nail biting, chewing pens, or biting other objects can place additional strain on the masticatory muscles and temporomandibular joints.

The relationship between nighttime teeth grinding and painful temporomandibular disorders in children is not straightforward.

Not every child who grinds their teeth develops a joint problem. A clearer association has been observed between painful disorders and frequent teeth clenching while awake.

Inflammatory and Systemic Diseases

Certain rheumatological conditions, including juvenile idiopathic arthritis, may affect the temporomandibular joint.

Sometimes joint involvement may occur with few or no obvious symptoms.

For this reason, when a child has such a condition, coordination between the rheumatologist, paediatric dentist, orthodontist, and a clinician experienced in temporomandibular joint disorders may be important.

Developing Bite and Facial Asymmetry

Certain bite characteristics may be seen more frequently in patients with temporomandibular symptoms, but current evidence does not support the idea that malocclusion is the only or primary cause of all temporomandibular disorders.

Similarly, orthodontic treatment should not be presented as a universal method for treating or preventing TMJ problems.

Orthodontics has an important role in correcting specific disturbances in bite development and function, but treatment should be based on an accurate diagnosis rather than solely on the presence of clicking or pain.

Psychological and Emotional Stress and Sleep Disturbances

Stress, anxiety, insufficient sleep, and certain repetitive habits may increase tension in the masticatory muscles.

This does not mean that the symptoms are “only psychological”.

The pain is real, but in some children it may be maintained by a combination of physical, behavioural, and emotional factors.

What Symptoms May Suggest a Temporomandibular Joint Problem?

Signs of a Possible TMJ Problem in a Child

What Do You Notice?	What Could It Mean?	What Is Recommended?
Pain in front of the ear, jaw, or temples	Overload of the masticatory muscles or a problem involving the TMJ	Consult a paediatric dentist, orthodontist, or gnathologist
Pain or fatigue while chewing	Muscle tension, one-sided loading, or altered function	Observe whether the child chews only on one side and arrange an examination
Limited or painful mouth opening	Muscle spasm, inflammation, or a joint disorder	Do not force the child to open the mouth; seek professional assessment
Jaw locking	Disturbance in the movement of the articular disc or another joint dysfunction	Prompt examination is recommended
Clicking or popping without pain	May be a harmless functional finding	Monitoring, particularly when there is no pain or movement restriction
Clicking accompanied by pain	Possible overload or disturbance of joint movement	Assessment by a clinician experienced in TMJ disorders
Chewing only on one side	Discomfort, dental pain, malocclusion, or an established habit	Dental and orthodontic examination
Jaw deviation during opening	Asymmetric joint or muscle function	Orthodontic and functional assessment
Sudden change in the bite	Joint, muscular, or traumatic disturbance	Do not delay an examination
Teeth grinding or clenching	Bruxism, stress, sleep disturbance, or a temporary childhood habit	Do not use a splint without diagnosis; monitor for pain and tooth wear
Tooth wear or chipping	Prolonged or excessive loading	Dental evaluation and follow-up
Morning headache and tired jaw	Nighttime clenching, poor-quality sleep, or muscle tension	Assessment of bruxism, sleep, and breathing
Sleeping with the mouth open and frequent snoring	Restricted nasal breathing or sleep-related breathing disorder	Consultation with a paediatrician and ENT specialist
Pain or a change in the bite following an injury	Possible injury to the teeth, jaw, or temporomandibular joint	Examination as soon as possible

Important: A single symptom does not necessarily indicate the presence of a disorder. The strongest reasons to seek professional assessment include pain, restricted movement, jaw locking, a change in the bite, marked asymmetry, or symptoms following trauma.

Can a Jaw Problem Cause Headaches, Ear Pain, or Neck Discomfort?

Temporomandibular disorders may be associated with pain in the face, temples, area in front of the ear, and masticatory muscles, and they may sometimes be accompanied by headaches or neck discomfort.

However, this does not mean that every headache, episode of dizziness, or sensation of a blocked ear is caused by the temporomandibular joint.

Similar symptoms may have dental, neurological, ear-nose-throat, ophthalmological, or other medical causes.

For this reason, proper diagnosis includes distinguishing joint and muscular pain from conditions involving the teeth, ears, sinuses, and other structures.

It is not scientifically justified to automatically attribute symptoms such as limb tremor, changes in the sense of smell, or all postural problems to the temporomandibular joint.

Such symptoms require an independent medical assessment.

What Is the Importance of Sleep and Breathing?

Restful sleep and unrestricted nasal breathing are important for a child’s overall development.

Persistent mouth breathing should not be viewed simply as a “bad habit”. It may be associated with enlarged adenoids or tonsils, allergic rhinitis, nasal obstruction, anatomical characteristics, or other causes.

Pay particular attention if your child:

• regularly sleeps with their mouth open;
• snores loudly or almost every night;
• has restless sleep and frequent awakenings;
• sleeps with the head extended unusually far backwards;
• has observed pauses in breathing;
• sweats excessively during the night;
• is difficult to wake or wakes with a headache;
• experiences daytime sleepiness, irritability, or difficulty concentrating;
• continues bedwetting beyond the expected age.

When such signs are present, the child should be examined by a paediatrician and an ear, nose, and throat (ENT) specialist.

If a sleep-related breathing disorder is suspected, consultation with a sleep medicine specialist and a sleep study may be necessary.

An orthodontist can assess jaw and dental arch development but cannot independently diagnose obstructive sleep apnoea.

Should Parents Be Concerned When a Child Grinds Their Teeth?

Grinding or clenching the teeth is known as bruxism.

It may occur during sleep or while awake and is seen in both children and adults.

Many cases of childhood bruxism are mild and temporary and do not require specific treatment.

However, bruxism should not be described as a beneficial mechanism for stimulating the growth of the temporomandibular joint. There is insufficient evidence to claim that teeth grinding promotes healthy jaw development.

An examination is recommended when there is:

• significant tooth wear or chipping;
• morning jaw pain or fatigue;
• frequent headaches;
• tooth sensitivity;
• painful or restricted mouth opening;
• loud snoring, mouth breathing, or pauses in breathing;
• daytime teeth clenching;
• behavioural changes, anxiety, or severely disturbed sleep.

The presence of bruxism does not automatically mean that a child needs an occlusal splint.

In growing children and during the transition from primary to permanent teeth, intraoral appliances should be prescribed individually and monitored carefully because tooth eruption and jaw growth are still continuing.

What Are the Risks of Leaving a Problem Unaddressed?

The consequences depend on the cause and severity of the condition.

For some children, symptoms are temporary and improve with conservative measures. For others, persistent pain may interfere with eating, speaking, sleeping, concentration, and normal daily activities.

A significant untreated disorder may lead to:

• worsening pain and muscle tension;
• restricted movement of the lower jaw;
• avoidance of hard foods and one-sided chewing;
• further tooth wear or damage in severe bruxism;
• reduced sleep quality;
• progression from occasional pain to a chronic complaint;
• changes in growth and facial asymmetry in certain cases of trauma, joint inflammation, or serious structural disease.

However, it would be incorrect to claim that every untreated TMJ problem will inevitably lead to spinal deformity or damage throughout the body.

The relationships between the bite, posture, and musculoskeletal symptoms are complex and should be assessed individually.

How Is the Diagnosis Made?

Diagnosis begins with a detailed discussion of the symptoms, including:

• when they began;
• whether pain is present and where it is felt;
• whether symptoms occur during chewing or mouth opening;
• whether there has been an injury;
• whether the jaw clicks or locks;
• whether headaches, teeth clenching, or sleep disturbances are present;
• whether the bite has changed.

This is followed by a clinical examination, which may include:

• observing opening and closing of the mouth;
• measuring the range of movement;
• assessing deviation or asymmetry;
• palpation of the temporomandibular joints and masticatory muscles;
• checking for pain and joint sounds;
• evaluating the teeth, bite, and functional movements;
• analysing facial proportions and growth.

Imaging is not necessary for every clicking sound or minor complaint.

A panoramic X-ray, CBCT, or MRI may be recommended only when the clinical findings indicate a need for further investigation.

MRI is particularly informative for evaluating the articular disc and soft tissues, whereas CBCT primarily provides information about the bony structures.

Which Specialist Should You Consult?

The initial assessment may be performed by a paediatric dentist or an orthodontist with experience in bite development and temporomandibular disorders.

Depending on the findings, a multidisciplinary approach may be necessary, involving:

• a gnathologist or orofacial pain specialist;
• an oral and maxillofacial surgeon;
• a paediatric rheumatologist;
• a paediatrician;
• an ENT specialist;
• a sleep medicine physician;
• a physiotherapist experienced in jaw and facial disorders;
• a speech therapist or orofacial myofunctional therapist;
• a psychologist when stress, anxiety, or behavioural factors contribute to the symptoms.

Not every child needs to see all of these specialists.

The appropriate team is determined by the individual diagnosis rather than by a predetermined protocol.

When Is the First Orthodontic Examination Recommended?

A first preventive orthodontic assessment is recommended no later than around the age of seven.

At this age, children usually have a combination of primary and permanent teeth, making it possible to identify early problems involving eruption, the bite, and jaw growth.

This does not mean that every seven-year-old child needs to begin orthodontic treatment.

For many children, the most appropriate approach is periodic monitoring, with treatment beginning only when the appropriate stage of growth has been reached.

An earlier examination may be recommended in the presence of visible asymmetry, crossbite, difficulty chewing, trauma, early loss of primary teeth, or significant underdevelopment of the lower jaw.

What Can Parents Do?

Do not observe only the alignment of your child’s teeth. Pay attention to how the child functions as well:

• Does the child chew comfortably on both sides?
• Is there pain during eating?
• Does the mouth open freely and symmetrically?
• Does the child sleep with the mouth open?
• Does the child snore?
• Does the child clench their teeth during the day?
• Does the child wake with a headache or tired jaw?
• Has the bite changed following an injury?
• Does the child avoid hard foods without an obvious reason?

When pain is present, do not encourage the child to “exercise” or forcefully move the jaw.

Temporarily avoiding very hard or chewy foods, chewing gum, and excessively wide mouth opening may reduce strain, but these measures do not replace professional assessment.

Do not use over-the-counter occlusal splints or begin exercises found online without a diagnosis.

Treatment in children should be conservative, reversible, and appropriate for their ongoing growth.

Professional recommendations prioritise education, modification of contributing habits, appropriate physiotherapy, and other conservative methods.

Irreversible procedures involving the bite or temporomandibular joint should not be undertaken solely on the basis of non-specific symptoms.

Why Does the Temporomandibular Joint Remain Important in Adults?

Growth eventually ends, but the temporomandibular joints and masticatory muscles continue to be exposed to daily functional forces.

Prolonged teeth clenching, stress, sleep disturbances, trauma, certain systemic diseases, and excessive loading may also lead to pain and reduced function in adults.

The fundamental principle remains the same: the actual source of the symptoms needs to be identified.

Treatment should not begin with irreversible changes to the bite, grinding of the teeth, or surgical procedures.

For most patients, the first step is a conservative, individually planned approach.

The Most Important Points for Parents to Remember

Not every clicking sound indicates disease.

Not every case of teeth grinding requires an occlusal splint.

And not every malocclusion causes a temporomandibular joint problem.

However, pain, restricted movement, jaw locking, changes in the bite, marked asymmetry, and symptoms following trauma should not be ignored.

A timely examination can help distinguish a normal stage of development from a condition that requires monitoring or treatment.

If you have concerns, consult an orthodontist or gnathologist who can evaluate not only the teeth but also the overall function of the masticatory system, jaw development, and the individual needs of the child.