Mouth breathing can lead to sleep disordered breathing (SDB), which is gaining more recognition in the medical community. Studies show that it could be present in up to 25 per cent of young children. Signs include mouth breathing, noisy breathing, teeth grinding and snoring. If not treated, it could lead to the more worrisome obstructive sleep apnoea.
SDB has a significant impact on children’s behaviour, affecting their ability to focus and learn at school. Children with SDB may appear hyperactive or distracted in class, when they are in fact exhausted. They perform below their aptitude, and may be branded as troublemakers. Some of these children are misdiagnosed with ADD or ADHD.
There can be significant physiological consequences to long-term disordered sleep as it can even disrupt heart function.
Children do not choose to mouth breathe. In fact, they do so out of necessity. Their nasal passages may be blocked due to enlarged adenoids, or a deviated septum. Congestion can also impede airflow through little noses, with allergies being the most common culprit. Kids with tongue ties are also more likely to mouth breathe, as it may be more difficult for them to close their lips.
Swallowing and speaking
Breathing through your mouth not only robs you of sleep, it also affects basic functions such as eating. Children who mouth breathe tend to push their tongue forward against their front teeth, or between their teeth, when they swallow. Eating might appear to be a bit of a messy affair, but they are simply trying to breathe.
Constant pressure of the tongue on the front teeth can lead to poor development of the jaws and hard palate, with weaker muscles in the cheeks and lips. It can also result in more dental caries, misaligned jaws and crooked teeth. Those who mouth breathe often develop a telltale long and narrow face, with a noticeably receding chin. Slouched posture is also a side effect.
All these structural changes can make biting, chewing and swallowing more difficult and less effective. As a result, children may experience more tummy aches. Predictably, they may take a long time to finish meals, laboriously working their way through basic biomechanical tasks that the rest of us take for granted.
Altered development of the mouth and jaw has further consequences as well – it affects the ability to speak. Speech requires a great deal of fine muscle control with the tongue and the lips. It also requires regulated breathing, with times when the lips must be closed to form the correct sounds.
The result is unclear speech. Children who are unable to enunciate properly are pressed to speak up and be more clear. Although they cannot, they are berated for not doing so, sadly undermining their confidence and self worth. Children who mouth breathe are also more likely to have lisps, or difficulty making correct “s” sounds.
Habitually breathing through your mouth can also impact more directly on your health. When we breathe normally through our nose, outside air is gently filtered, warmed and moistened by our nasal passages. If you ever blow your nose after a polluted day, you will see how effective your nose can be in filtering inhaled air.
However, when we breathe through our mouths, air does not go through this important processing step. The constant flow of dry, unfiltered air can lead to irritated, enlarged tonsils and sore throats. Children who mouth breathe often have more frequent bouts of illness, and may miss school more often than their nose-breathing peers.
Teachers, dentists, doctors
Experienced teachers who are aware of the connection between mouth breathing and school performance can be invaluable in helping to flag the problem. Currently, however, it is much more challenging to observe children in the classroom with this issue, with so many still wearing a mask.
Fortunately, there is another way to identify the issue. Dentists should be asking questions about breathing during routine examinations.
A comprehensive dental examination for children should include a thorough screening to identify risks related to sleep disordered breathing
According to Dr Irene Lau, a paediatric dentist here in Hong Kong, “A comprehensive dental examination for children should include a thorough screening to identify risks related to sleep disordered breathing, including mouth breathing, snoring, enlarged tonsils, tongue function and positioning.”
If parents notice that their child is breathing through their mouth they should see their family doctor and request a referral to an ear, nose and throat doctor (ENT) – also known as an otolaryngologist. An ENT will have the education and training to thoroughly investigate the child’s airways to see if there are any structural abnormalities that can lead to disordered breathing.
If allergies are causing airway blockages, parents should consult an allergist as soon as possible so the child can he helped to breathe more freely.
Early intervention
Early intervention is key to preventing further issues, and will allow children to quickly make up lost ground.
Further support from a speech therapist trained in orofacial myofunctional therapy can be necessary to teach children to breathe through their nose, position their tongue properly and learn the correct way to swallow.
So, back to our story about Harry. Luckily, he had a knowledgeable dentist who noticed the signs of his sleep disordered breathing. With some help from an ENT and speech therapist, he was able to breathe better, sleep better and eat more comfortably. Because he was well-rested, he was able to focus and concentrate in class, and meet his academic goals at school.
Stephanie Eber is speech and language pathologist at the Jadis Blurton Family Development Centre. She received her degree in speech pathology from the University of Sydney, Australia. She has worked in hospitals, schools and disability organisations and provided lectures to students at the University of Hong Kong and the Chinese University of Hong Kong.
