Parents Concerns

PARENT CONCERNS - A 3 Year Old Child
With Tongue Thrusting and Open Bite
ABSTRACT A parent question about a 3 year old with tongue thrusting and an anterior open bite is
responded to.

PARENT QUESTION: Our 3 year old son had an initial dental evaluation by our family dentist. He
told us that our son has an anterior open bite with a deviant swallow, tongue thrust and lisp. Our son
also sucks his thumb. Should we be concerned?

ANSWER I am disappointed that the dentist has labeled your 3 year old child with various negative-
sounding terms. A dentist, with good intentions, may get carried away by identifying and labeling some
behaviors as abnormal that are quite normal for this age group. What the dentist reports are behaviors
that are not cause for immediate concern or action. While I appreciate that the dentist wanted to be
thorough, there is no need to spring into action at this time with orofacial myofunctional therapy or with
concerns or procedures, such as orthodontic treatment.

SPEECH AND OTHER ORAL FUNCTIONS: Here are some details regarding oral functions: At
age three, the predominant tongue function is still in the horizontal plane. All 3 year olds can easily
protrude the tongue. Vertical and lateral movements of the tongue, however, are often not well
controlled. Substitution of "th" for "s" (or lisping) is a common example of this, and is quite normal at
his age level. I would not recommend having your child seen by a speech-language pathologist or
orofacial myologist
for therapy at this age, as this could do more harm than good in calling attention
to your son’s tongue placement. If, however, you feel that your child is not developing language skills
appropriately, the consultative skills of a speech-language pathologist would be comforting and
helpful at this time. Since you have not noted any issues with your son's speech, it is also likely that he
has no language delays since you apparently understand what he is saying and he is communicating.
If your son can correct his pronunciations when stimulated with a verbal cue, this is an excellent sign
that he will be able to achieve normal speech along the developmental speech table. Many speech
sounds and blended sounds in words (such as “snow”, “swing”, “break”) are not expected to be
mastered until around age 5.

At age 3, thumb sucking is also a normal behavior. This will be discussed later in this reply to your

TONGUE THRUSTING AND THE “DEVIANT” SWALLOW: Let's discuss the terms “tongue thrusting” and "deviant"
swallowing. I dislike the label of "deviant swallow" that the dentist used because it is not an accurate description of anything except
in rare instances when a person aspirates air or food during a swallow. There is nothing deviant about a swallow from a
physiological standpoint if food gets down into the esophagus and stomach rather than being aspirated into the lungs. Some
continue to use this term rather than the more widely accepted term "tongue thrust swallow", which describes the initiation phase of
a swallow as involving a forward protrusion of the tongue tip between the teeth rather than an elevation of the tongue tip.

Tongue thrusting itself can occur in speaking and/or swallowing. Many dentists fear and claim, incorrectly, that thrusting the tongue
against or between the anterior (front) teeth during speaking or swallowing will move or push the teeth forward and create either
incisor protrusion or an open bite at the front of the mouth. This is an inaccurate view of tongue thrusting, and what is claimed does
not occur as a result of tongue thrusting. Actually, it is the rest posture of the tongue that is the link between the tongue and changes
in the position of teeth

FORWARD, INTERDENTAL REST POSTURE OF THE TONGUE: A tongue thrust can be, and is often accompanied by a
forward, interdental rest posture of the tongue. When the tongue rests forward, the lower jaw is hinged open slightly and the
presence of a resting tongue between the front teeth can create an open bite over time. To do so, the front teeth are inhibited from
full eruption while the back teeth over-erupt because the mouth is hinged open for hours at a time beyond the normal range. This
process is known as "differential eruption". Clinical research has demonstrated that the forward resting posture of the tongue is
linked to dental variations at the front of the mouth such as open bite, while a tongue thrust may only play a minor or contributory
role. Overall, the tongue is viewed as an “adaptive” structure that seeks spaces already open and tends to rest there. Many in
dentistry continue to presume an improper cause and effect between thrusting and tooth position such as open bite or incisor
protrusion. The bottom line is: don't worry about the tongue thrust at age three. By the time that the adult front teeth (incisors) erupt
(age 6 onward) tongue thrusting may be of some concern, although some children spontaneously outgrow a thrust and even an
anterior open bite.

When a tongue thrust and a forward rest position of the tongue at rest are seen, they should serve as a clue to look at the posterior
That is, what you see happening at the front of the mouth should signal a need to evaluate what is happening at the back of
the mouth and beyond, especially with the tonsils and adenoids. The reason for this is that unresolved airway issues and allergic
rhinitis are the primary reasons why tongue thrusting develops. As well, spaces created anteriorly encourage thrusting and a
forward rest posture as the tongue assumes an opportunistic role.

TONSILS AND ADENOIDS: Here are some details about tonsils and adenoids: In a child of age 3, the tonsils and adenoids are
already expected to be large. The location of tonsils is at the gateway between the oral cavity and the back of the throat (the
oropharynx). Large tonsils can diminish the size of the opening into the oropharynx (the oral isthmus between the tonsils) and can
also compete with the base of the tongue for space, causing the tongue to rest or move forward to maintain the airway. With large
tonsils, the tongue may thrust forward in the beginning part of the swallow to get food past the small space between the tonsils (the
oral isthmus), that is, as food is passed between large tonsils, the tongue moves forward to enlarge the airway and facilitate the
swallow. In this situation, with a small airway due to large tonsils and/or adenoids, the last thing that should be done is to try to
retrain the tongue out of a tongue thrust.

The adenoids are a mass of lymphoid tissue attached to the back and top of the nasopharynx. You will not be able to visualize them
by looking in your son's mouth since they are hidden behind and above the soft palate. In some children, the adenoids are so large
that they obstruct or partially obstruct the back entrance into the nose. As a result, a child is forced to breathe through the mouth.
Pediatricians are well equipped to follow the development of the tonsils and adenoids. Just because tonsils and/or adenoids are
large does not signal the need for their removal. Pediatricians are appropriately conservative about surgically removing tonsils and
adenoids. There is growing evidence that these lymphoid tissue masses contribute to the body's immunological development,
experience and responses, since their location can act as a filtering thermostat for what is being introduced into the throat, nose
and lungs during breathing. The importance of tonsils and adenoids in contributing to the development of the body’s immunologic
development is most active between ages 3 and 6 years.

The tonsils and adenoids have a growth cycle. They are expected to be large by age three and remain large until around age 12,
when these lymphoid tissue masses then go through a process of self-reduction in size called involution or atrophy of tonsils and
adenoids. Without surgery, many individuals have little or no tonsils and adenoids remaining by age 20 simply as a normal process
of the growth cycle which involves tissue proliferation and then involution. Where there is a history of tonsillitis or adenitis in
childhood, the growth and involution cycle for tonsils and adenoids may not conform to the norm.

THUMB SUCKING: Your son's thumb sucking habit may be linked to his developing open bite if the thumb is in his mouth for
hours per day. Nonetheless, I would
not recommend trying to get the thumb out of his mouth at age 3. It provides comfort and tastes
good. Actually, during thumb sucking, the body releases endorphins into his system, resulting in a pleasurable experience; thus,
there is a biochemical encouragement for the continuation of this habit. Dentists do not worry about thumb sucking until around age
6. Below age 6, most in dentistry would accept the development of an open bite rather than recommend therapy to cease the
sucking habit. However, myofunctional clinicians would begin working to eliminate a sucking habit at age 5 years because
youngsters who go to school with a sucking habit can experience teasing, learning and socialization problems. But a 3 year old,
however, the thumb habit can be ignored, and also the thrusting and open bite for several years. For the near future, as long as your
son is sucking his thumb, the tongue thrusting will not be expected to spontaneously resolve.

APPLIANCES TO BREAK ORAL HABITS: Here is some advice that should serve you well: If anyone in dentistry ever
recommends inserting an appliance into your child's mouth for thumbsucking or tongue thrusting, please decline the invitation. In
my opinion,
there is no place or need for appliances in habit treatment, and I am prepared to vigorously argue this opinion with
any in dentistry who may disagree. Behavioral (non-invasive and non-punitive) approaches to habit cessation work well, as provided
by orofacial myologists. The problem with oral habit appliances is not only that they are punitive but also, and just as important, any
and all of the appliances tend to hinge the lower jaw open. This encourages continued eruption of back upper teeth through
differential eruption. The result is an increase in an anterior open bite. Appliances can create an even larger problem by their use,
rather than serving to reduce or eliminate a habit pattern. Also, children are quite capable of bypassing the appliance with the
tongue under the prongs/rakes/spikes, etc., so the appliances seldom work effectively and as intended. Those using dental
appliances for oral habits also ignore the fact that it is the forward rest posture of the tongue that is the link with dental changes
rather than the thrusting, which is the intended object of appliance wear.