Definition and Difference from Nasal Breathing
Nasal breathing is the body’s natural and preferred way to breathe. In contrast, mouth breathing bypasses these important functions, allowing unfiltered air to enter directly and potentially affect overall health.
Common Causes of Mouth Breathing
Mouth breathing in children can stem from several underlying issues, including:
- Allergies: Seasonal or chronic allergies can cause nasal inflammation and congestion, making it difficult to breathe through the nose.
- Enlarged Tonsils or Adenoids: Swollen tissues in the back of the throat and nasal passage can physically obstruct airflow.
- Nasal Blockages: Deviated septum, polyps, or chronic sinus infections can restrict nasal airflow, prompting mouth breathing.
- Habitual Behavior: In some cases, children develop mouth breathing as a habit, even after the physical cause has resolved.
How to Identify Chronic Mouth Breathing in Children
Parents may notice several signs that indicate a child is consistently breathing through their mouth. These include:
- Sleeping with an open mouth
- Frequent snoring or noisy breathing at night
- Dry lips and mouth upon waking
- Daytime fatigue or irritability due to poor-quality sleep
- Difficulty concentrating in school
- Changes in facial appearance or dental issues
When a child breathes through their mouth, it tends to dry out the oral tissues, reducing the amount of protective saliva present. Saliva plays a vital role in neutralizing acids, washing away food particles, and keeping harmful bacteria in check. Without it:
- The mouth becomes more acidic, leading to faster enamel erosion.
- Bacteria can thrive, increasing the risk of tooth decay and gum disease.
- Children may complain of bad breath or experience a sticky, dry feeling in their mouth, especially in the morning.
Chronic dry mouth creates a perfect storm for cavities to develop quickly and more frequently than in children who primarily breathe through their nose.
Mouth breathing can affect the position of the tongue and the development of facial muscles. When a child keeps their mouth open consistently, their tongue tends to rest low in the mouth instead of against the palate (roof of the mouth). This lack of tongue pressure on the upper jaw can result in:
- Narrow, high-arched palate formation
- Crowded or crooked teeth due to limited space
- Open bite or overbite issues caused by improper muscle balance
These alignment problems often require orthodontic treatment and may become more severe if left unaddressed during early development.
The constant flow of air in an open mouth can dry out the gum tissues and potentially delay the eruption of primary (baby) or permanent teeth. Improper oral posture associated with mouth breathing may also interfere with the natural path of erupting teeth, leading to abnormal spacing, impaction, or uneven bite alignment.
One of the most noticeable outcomes of prolonged mouth breathing is what's commonly referred to as “long face syndrome.” This occurs when the lower jaw grows downward rather than forward due to poor oral posture, leading to:
- An elongated facial appearance
- Narrow upper and lower jaws
- A reduced nasal airway, further reinforcing the mouth breathing habit
These structural changes can also result in an underdeveloped chin and an increased distance between the upper lip and nose.
Mouth breathing often shifts the natural positioning of the jaw and tongue. Ideally, the tongue should rest against the roof of the mouth, supporting the development of the upper jaw. However, in mouth breathers:
- The tongue rests low and forward in the mouth
- This leads to an open-mouth posture, even when at rest
- The lower jaw tends to hang down and backward
This misalignment contributes to malocclusion (bad bite) and can also affect speech development, chewing efficiency, and nighttime breathing quality.
As the jaw and midface develop unevenly, children may develop facial asymmetry or imbalanced features, such as:
- A drooping lower lip
- A recessed chin
- Flattened cheeks
- Dark circles under the eyes due to poor sleep and sinus issues
Children who breathe through their mouths often do not get restful, restorative sleep. This can result in:
- Feeling tired or sluggish during the day
- Difficulty focusing in school or completing tasks
- Frequent yawning or low energy despite a full night’s sleep
Poor sleep quality affects memory retention, learning abilities, and emotional regulation—critical components of healthy childhood development.
Chronic mouth breathing is commonly associated with obstructive sleep apnea (OSA) and snoring. These conditions occur when airflow is partially or completely blocked during sleep, often due to enlarged tonsils, adenoids, or a narrowed airway. Signs of possible OSA include:
- Loud, regular snoring
- Gasping or pauses in breathing at night
- Restless sleep or frequent waking
- Mouth breathing while asleep, even when nasal breathing is possible
Undiagnosed and untreated sleep apnea can hinder physical growth, increase the risk of metabolic problems, and contribute to behavioral issues.
Studies have shown a strong link between poor sleep due to mouth breathing and symptoms that mimic Attention-Deficit/Hyperactivity Disorder (ADHD). Children may exhibit:
- Impulsivity or hyperactivity
- Trouble following instructions
- Mood swings or irritability
- Short attention span
Myofunctional therapy is a series of exercises designed to correct improper oral habits, strengthen facial muscles, and train the tongue to rest in the proper position (on the roof of the mouth). This therapy can help:
- Encourage nasal breathing
- Improve tongue posture and swallowing patterns
- Support facial symmetry and jaw growth
In cases where mouth breathing has already impacted dental alignment, early orthodontic intervention may be necessary. Treatment options may include:
- Palatal expanders to widen a narrow upper jaw
- Braces to correct misaligned teeth and bite
- Space maintainers if early tooth loss has occurred
Orthodontists often work closely with pediatric dentists and myofunctional therapists to coordinate care and guide proper facial development.
Encouraging nasal breathing is essential, especially after removing physical obstructions or treating allergies. Simple, daily breathing exercises—often guided by a therapist or trained professional—can help retrain a child’s natural breathing habits.
In addition, maintaining good nasal hygiene is key to keeping the airways open and clear. Strategies include:
- Using saline sprays or nasal rinses
- Managing allergies with medication or avoiding triggers
- Ensuring proper hydration to keep mucus thin and manageable
The earlier mouth breathing is addressed, the better the outcome for your child’s health and development. Timely treatment can:
- Prevent long-term changes in facial structure
- Reduce the need for complex orthodontic work later
- Improve sleep quality, behavior, and academic performance
- Promote proper jaw alignment and oral function
Parents should be proactive in raising concerns with their pediatric dentist or doctor if they notice signs of persistent mouth breathing. Even subtle symptoms—like snoring, dry mouth, or facial elongation—can signal underlying issues that need attention.