Mouth Breathing

What Is Mouth Breathing?

Mouth breathing is respiration through the mouth instead of the nose, and the reason may be anatomic deformity, habitual or obstruction to the nasal passage. Mouth breathing causes continuous exposure of tissues of the anterior part of the oral cavity to inspired air. Patterns of respiration are the primary determinant of the position of the tongue and jaw. So, when there is an alteration in the respiration pattern, that means when an individual breathes through the mouth instead of the nose, there will be a loss of equilibrium. This causes alteration in pressure that affects normal jaw growth and tooth position, leading to malocclusion development. In total, mouth breathing has an impact on the development of the maxillofacial region, occlusion, and muscle tone.

How Is Mouth Breathing Classified?

Mouth breathing is classified into three different categories:

1. Obstructive breathing.

2. Habitual breathing.

3. Anatomic breathing.

4. Bad habit of staying and sleeping with your mouth open is not related to medical conditions.

1. Obstructive Mouth Breathing - In the obstructive type of mouth breathing, there is complete obstruction of airflow through the nasal passages. As there is obstruction, there is difficulty in breathing through the nose, and so the child is forced to breathe through the mouth.

Clinical Conditions Featuring Obstruction of Nasal Passage:

1. Enlarged nasal turbinates.

2. Deviated nasal septum.

3. Allergic rhinitis.

4. Enlarged adenoids.

5. Chronic inflammation of nasal mucosa.

6. A short upper lip that causes difficulty in proper lip seal.

7. Obstruction of the larynx.

8. Obstructive sleep apnea.

9. Children who are ectomorphs having tapering faces and nasopharynx are most commonly prone to nasal obstruction.

10. Thumb sucking or other oral habits are precipitating factors.

2. Habitual Mouth Breathing:

In this, the child breathes through merely because of habit, even if abnormal obstruction or root cause is removed.

3. Anatomic Mouth Breathing:

Individuals having a short upper lip, in that case, there will not be complete closure without undue effect.

What Is the Pathogenesis of Mouth Breathing?

Mouth breathing causes a change in the pattern of breathing that leads to a change in the jaw, tongue, and head position. The balance between tongue activity and masticatory muscle actions is disturbed. Development of the palate gets hampered when there is a disturbance in airflow through the nasal cavity. In mouth breathers, because of the backward and downward position of the tongue, there will be a lack of support of the tongue during hard palate development, which leads to deep palate development in mouth breathers.

In mouth breathers, there is difficulty in inspiration, so that the head tends to be in a forward position, which makes inhalation easier through the mouth. The downward and backward placement of the lower jaw causes its distal position, which ultimately leads to increased overjet. Strong cheek muscles apply an increased external force to the upper jaw, which causes the change of form to V-shaped. It results in,

• Alteration in equilibrium pressure of nasal and oral cavity.

• Altered position of tongue and jaws.

• Mandible backward and downward position.

• Loss of equilibrium between teeth, jaws, and musculature (masticatory and tongue).

• Adenoid facies or long face syndrome.

What Are the Factors Considered for Mouth Breathing?

Transition to oral breathing occurs in the following conditions:

1. The ventilation exchange rate reached 40-45 l/min.

2. Heavy mental concentration causes increased airflow.

3. In cases of partial nose obstruction, or there is a tortuous passage.

4. Swelling of nasal mucosa accompanying common cold.

5. Chronic respiratory obstruction is produced due to inflammation within the naso-respiratory system.

6. Pharyngeal tonsils and adenoids.

What Are the Clinical Features of Mouth Breathing?

• Hampered growth of the maxilla.

• Narrow and high arched palate.

• Crowded dental arch.

• The lower position of the tongue leads to the prognathic mandible.

• Hyperactivity of the buccinator muscle restricts the development of the maxilla.

• Bilateral crossbite.

• Inflamed and irritated gingival tissue in the anterior maxillary arch, classic rolled marginal gingival and enlarged interdental papilla.

• Interproximal bone loss is associated with the presence of deep pockets.

• The extraoral appearance of such patients is termed ‘adenoid faces’ having a typical long face and narrow faces.

• Open bite - Downward and backward position of the tongue leads to downward and backward rotation of mandible leads to open bite.

How Is the Breathing Pattern Examined?

One can access the type of breathing pattern with the following test.

1. Cotton Pledget Test: Butterfly-shaped cotton is placed below the nostrils, and the patient is asked to breathe then observed. If the patient is a nasal breather, he will displace the cotton pledget on expiration, whereas the mouth breather will not.

2. Mirror Test: In this test, the double-sided mirror is used. It is kept in front of the nostrils, and if the patient is a mouth breather, there will be a cloud with condensed moisture on the side of the mouth.

3. A Sip of Water: When the patient can hold water in the mouth for up to or more than one minute, the patient can breathe through the nose.

4. Squats: If the patient can do several squats with complete contact of mouth and lips, he can breathe through the nose.

5. Observation of Nostrils: Inactive alar muscles (nose muscles) in mouth breathers, i.e., they do not change their size while breathing.

How Is Mouth Breathing Managed?

Mouth breathing is managed by,

1. Elimination of cause.

2. Symptomatic treatment.

3. Interception of habit - Mouth breathing needs treatment if it continues even after removal of the obstruction. Correction can be done by,

   1. Physical exercise.

   2. Lip exercise.

   3. Myotherapy.

   4. Oral screen.

Oral Screen - This appliance is used most effectively as it prevents air entry into the oral cavity, so ultimately the patient is forced to breathe through the nose. The material used for the construction of the oral screen should be compatible with oral tissues. After using the oral screen for about 3-6 months, open bite correction can be obtained.

Pre Orthodontic Trainer - Pre orthodontic trainer, is used in patients having the habit of mouth breathing, tongue thrusting, and thumb sucking.

Correction of the Malocclusion - Mechanical Appliances:

1. Oral shield appliance is used in children with class I malocclusion with anterior spacing.

2. Monoblock activator can be used in children having class II division I dentition without crowding.

3. Chin cap can be used in patients having class III malocclusion.

In cases of allergic rhinopathy, mouth breathing will be due to nasal obstruction, consultation with an ENT surgeon is advised. For habitual breathers, pre-orthodontic therapy are useful, such as vestibular screen, breathing exercises. Holding a piece of cardboard is a myofunctional exercise to improve lip seal.

Conclusion:

When people are unable to breathe through their nose, they develop the habit of breathing through their mouth. The immediate and critical difficulty of acquiring adequate air may be solved by mouth breathing. However, mouth breathing can become a difficult habit that can lead to sleep issues, dental problems, and changes in facial structure. If suspecting mouth breathing, consult a healthcare professional. They will suggest therapies or medications to remedy the issue.