Mouth Breathing During Sleep Linked to Obstructive Sleep Apnea Risk

As winter cold gradually subsides, more people are reporting sleep discomfort during the seasonal transition. Indoor heating and dry air trigger nasal congestion and rhinitis, making it difficult to breathe through the nose.

When nasal breathing becomes difficult, people tend to sleep with their mouths open, a habit known as "mouth breathing." This can cause the tongue and soft palate to block the airway, worsening obstructive sleep apnea symptoms.

According to data released Wednesday by the Health Insurance Review and Assessment Service, the number of sleep apnea patients reached 184,255 in 2024, approximately double the figure from 2020. Obstructive sleep apnea (OSA), the most common type, is a condition where the upper airway repeatedly becomes blocked during sleep, causing awakenings.

Patients breathe normally during the day but make choking sounds during sleep. A diagnosis of obstructive sleep apnea is made when episodes of apnea (breathing stops for more than 10 seconds) or hypopnea (shallow breathing) occur five or more times per hour.

The condition extends beyond sleep deprivation and chronic fatigue. Prolonged symptoms increase the risk of cardiovascular diseases such as hypertension, myocardial infarction, and stroke, as well as diabetes.

Continuous positive airway pressure (CPAP) therapy, which involves wearing a mask that delivers air during sleep, is recommended as first-line treatment for obstructive sleep apnea. However, many patients fail to adapt due to nasal and oral discomfort, or cannot use the device due to structural nasal blockages from rhinitis or sinusitis. Many patients also resist wearing a mask every night.

Dental treatments offer an alternative. Dentists can precisely analyze a patient's oral structure, jaw joint condition, and airway shape to consider a range of options from non-surgical treatments using oral appliances and orthodontic devices to surgical treatments such as maxillomandibular advancement and maxillary expansion surgery.

For mild to moderate sleep apnea patients who cannot use CPAP, oral appliances provide a non-surgical alternative. Worn on the teeth during sleep, these devices push the lower jaw forward to widen the narrow airway space and move the tongue forward to secure the breathing passage. However, use is restricted for patients with heart disease, respiratory disease, chronic systemic disease, severe periodontal disease, denture users, those with temporomandibular joint disorders, or severe sinonasal conditions.

Maxillary expansion using orthodontic devices is another treatment option. When a narrow palate causes nasal breathing problems, rapid maxillary expansion (RME) can widen the hard palate and improve sleep apnea symptoms. This procedure uses an orthodontic device connected to the palate and molar teeth to expand the width of the nasal cavity and palate, improve mouth breathing, and reduce airflow resistance through airway expansion. While suitable for both adults and children, it is more effective for pediatric and adolescent patients aged 5 to 16, and consultation with an orthodontic specialist is recommended.

For severe patients who do not improve with oral appliances or those with clear skeletal problems, surgical treatment is considered. Maxillomandibular advancement (MMA) is similar to double jaw surgery and is effective for resolving sleep apnea. For patients with a receding chin or long, narrow "adenoid face," the procedure can provide both functional and aesthetic improvements.

"Sleep apnea carries significant complication risks if left untreated, so it is important to establish the most appropriate and safe treatment plan for each individual through specialist consultation," said Professor Hong Sung-ok of the Department of Oral and Maxillofacial Surgery at Kyung Hee University Hospital at Gangdong.