How Mouth Breathing Can Alter Facial Growth
A growing child can sustain permanent damage by
breathing improperly.
What determines the growth of your child's face?
The debate between supporters of the genetic hypothesis (inherited
traits) and those in favor of environmental influences (i.e.,
mouth breathing) is both old and not entirely resolved. Inheritance
is a basic and primary consideration for all facial growth. However,
research in growth centers in Europe, Canada and the United States
has shown that chronic mouth breathing contributes directly to
facial growth changes in children. These changes should be considered
as both abnormal and sometimes harmful to the growing bones and
muscles of the face.
Breath to humans is similar to sun light to a tree.
Both are necessary for normal growth and to sustain life. If a
tree receives sunlight from only one direction, the trunk and
branches grow toward the light source, and the tree will become
permanently de formed. If a child is unable to maintain a consistently
health nasal airway, the body will automatically program the system
to take breaths through the mouth. As with the trees, the entire
system must adapt to survive.
The adaptation from nasal to mouth breathing allows
a number of unhealthy things to happen. These changes can include
chronic middle ear infections, sinusitis, upper airway infections
and sleep disturbances such as snoring. In addition, mouth breathing
is often associated with a decrease in oxygen intake into the
lungs which can lead to a lack of energy. Mouth breathing children
may fatigue easily during exercise.
Mouth breathing can particularly affect the growing
face. The alterations will occur in the muscles associated with
the face, jaws, tongue and neck. The abnormal pull of these muscle
groups on bones of the face and jaws slowly deforms these bones,
eventually causing the jaws and teeth to be mismatched. The earlier
in life these changes take place, the greater the alterations
in facial growth.
The largest increments of growth occur during the
earliest years of life. In the first six months of life, the child's
weight doubles and in the first three years of life, height doubles--
something that never occurs again in a similar span of time. By
age four the facial skeleton has reached 60 percent of its adult
size, and by twelve, the age many orthodontists initiate treatment,
90 percent of facial growth has already occurred. Consequently,
if a child has chronic nasal obstruction during the early critical
growing years, facial deformities result, some subtle, some more
noticeable.
In adapting the mouth for chronic respiration, two
basic changes take place: the upper lip is raised and the lower
jaw is maintained in an open posture. The tongue, which is normally
placed near the roof of the mouth, drops to the floor of the mouth
and protrudes to allow a greater volume of air into the back of
the throat. Consequently, many mouth breathers also exhibit an
abnormal swallowing pattern.
As a result of these abnormal functions, children
who are mouth breathers are at risk of developing a well-documented
facial type commonly referred to as "adenoid faces,"
or long-face syndrome (Figure 1). These individuals can be characterized
by an open mouth posture, nostrils that are small and poorly developed,
a short upper lip, a toothy or gummy smile and (as a result of
the hanging posture of the lower jaw) a vacant facial expression.
Because there are abnormal muscular forces on the
jaws, tooth positions can also be affected and are often malposed.
Figure 1 demonstrates a severe malocclusion (bad bite) which includes
severe dental crowding and a crossbite where the upper jaw is
underdeveloped and fits inside the lower jaw
Untreated airway problems may so severely affect
facial growth that orthodontics alone cannot correct the malocclusion.
Corrective jaw surgery later in life, in addition to the necessary
procedures to open the nasal airway, may be required.
Whenever a child cannot breathe through the nose,
a mouth breathing mode of respiration occurs.
One cause of nasal airway obstruction in the child
is allergic rhinitis, where the nasal mucosa swells and blocks
the flow of air. Most allergic responses are initiated by airborne
particles, smoke, foods and pets.
Figure 1: Severe malocclusion attributable
to improper breathing.
While there is a genetic inclination to develop
allergies, research suggests that early treatment of allergic
disease can alter the course of allergic symptoms for a lifetime.
The adenoids and tonsils, frequently the target
of blame for airway obstruction, often are enlarged in response
to infection of the nose and sinuses. Since allergy predisposes
to infection, allergies should be controlled before the adenoids
and tonsils are removed. Thus untreated allergic children often
are seen to have a nasal airway obstruction even after the adenoids
and tonsils have been removed.
Other causes of reduced nasal respiration include
asthmas, nasal polyps, foreign bodies, deviated nasal septa, unreduced
fractures and congenital nasal deformities.
Treatment of nasal airway obstruction and mouth
breathing should involve a multidisciplined approach. The orthodontist
is uniquely qualified to monitor the growing face and may often
be in the middle of a referral pattern involving otolaryngologist,
allergists, pediatricians and other health care professionals.
If a young, rapidly growing child has chronic untreated nasal
obstruction and must breathe through his/her mouth all day and
all night, then the normal muscular activity of the face and jaws
will be altered.
Despite considerable interest in the problem among
health care professionals, there is still no uniform opinion regarding
the effects and treatment of a child with a mouth breathing habit.
Regardless, the following facts should be carefully evaluated:
- Mouth breathing is abnormal.
- Mouth breathing can affect the entire system.
- Mouth breathing can particularly affect the facial muscles
and bones of a growing child.
- Mouth breathing can cause facial deformities that are often
too severe for orthodontics to correct.
These individuals may require jaw surgery later
in life.
The American Association of Orthodontists recommends
a child's first visit to the family dentist at age two and an
orthodontic examination at age seven. However, parents should
be keenly aware that care of the developing face begins at birth,
and any nasal airway problems should be addressed as soon as they
are noticed. How your children breathe should not be taken for
granted.
This fine airway article was written by Dr. Stephen
Sherman and originally appeared in the Parent's Journal.