■ Mastication (chewing), in which food is crushed and mixed
with saliva to form a bolus for swallowing, is a complex
mechanism involving opening and closing of the jaw,
secretion of saliva, and mixing of food with the tongue.
■ Of course, chewing is also the essential first step of
digestion. Food must be chewed so it can be
swallowed easily and, when it arrives into the
stomach, be properly digested. Chewing leaves food
small enough for the gastric juices in the stomach
to further degrade it and reduce it to microscopic
MAIN MUSCLES OF MASTIFICATION
■ Medial pterygoid
■ Lateral pterygoid
■ Chewing disorders are chewing with the mouth
open; excessive chewing of gum; exclusive chewing
on one side; avoidance of foods with certain
textures such as meat, raw vegetables, seeds, some
fruit and nuts; preference for soft or pureed food;
pain or discomfort during chewing; abnormal jaw
■ Reasons: lack of intrest in food, pain in oral cavities, other problems.
■ Causes :chewing and biting actions of the jaw deform the thin layer
■ of soft tissue surrounding the teeth that are yet to appear,
■ forcing them outwards.
■ so a sluggish chewing can cause under developed teeth or
■ underdeveloped mastication muscles
■ Insufficient occlusal forces are injurious to the attachment
■ apparatus of the tooth
■ Prevention : counciling , eonsulting an ENT , or a den
Reasons: Various causes can be enumerated like deep carious lesions,
gingival overgrowths covering occlusal surface, pericoronal
and periodontal abscess, food lodgment, missing
teeth, habitual usage of only one side, improperly
Causes :unilateral mastication leads to hypofunction of the
attachment apparatus on the neglected or unused side. this
inturn affect periodontium.effects of nonfunction on
periodontium have been studied on humans and animals,2-6
indicating narrowing of the periodontal membrane, loss of
functional orientation of the principle fibers osteoporosis of
alveolar bone, and reduction of bone height.
Reasons : improperly aligned teeth or irregular contact
between upper and lower teeth, illnesses and other medical
conditions (such as nutritional deficiencies, pinworm,
allergies, endocrine disorders), and psychological factors
including anxiety and stress.
■ Awake bruxism may be due to emotions such as anxiety,
stress, anger, frustration or tension. Or it may be a coping
strategy or a habit during deep concentration.
■ Sleep bruxism may be a sleep-related chewing activity
associated with arousals during sleep.
■ Damage to your teeth, restorations, crowns or jaw
■ Tension-type headaches
■ Severe facial or jaw pain
■ Disorders that occur in the temporomandibular joints
(TMJs), located just in front of your ears, which may sound
like clicking when you open and close your mouth
■ Newborn babies are born with several important reflexes
that help them through their first weeks and months of life.
These reflexes are involuntary movements that happen
either spontaneously or as responses to different actions.
The sucking reflex, for example, happens when the roof of
a baby’s mouth is touched. The baby will begin to suck
when this area is stimulated, which helps with nursing or
■ It’s not uncommon for infants to suck on their thumbs or pacifiers,
especially to give themselves comfort. Over time, however, these
habits can have a negative impact on oral development. Here’s what
parents should know about pacifiers, thumb sucking and teeth.
■ Do Pacifiers Affect Teeth?
■ While babies love their pacifiers, many parents are rightly concerned
about their effect on oral development. Over time, a pacifier can
cause a mouth to grow improperly, leading to abnormal tooth
development, along with numerous other issues. For this reason, it’s
best to limit the use of pacifiers and discontinue their use altogether
as quickly as possible.
■ Do Pacifiers Make Your Teeth Crooked?
■ The long-term use of pacifiers changes both the alignment
of the teeth and shape of a developing mouth. As infants
mature, their jaws will grow around any device repeatedly
held within their mouths. Since the pacifier tips an infant’s
mouth upward, teeth can become crooked. Pacifiers can
also cause bite problems, along with alignment issues with
■ As the mouth forms around the device, babies can
develop common developmental irregularities
known as “pacifier teeth.” Unfortunately, this can
have long-term repercussions, requiring painful and
expensive dental treatments to restore the teeth
and jaw to a normal state.
■ There are also abnormalities when infants practice sucking in
■ Sucking abnormalities usually present as absence of the
sucking response, weakness or incoordination of sucking and
swallowing, or some combination of these problems
■ some common abnormalities are :
■ Prolonged sucking
■ Sluggish sucking
Prolonged Thumb Sucking
Reasons : prolonged sucking usually happens when the infant use
breastfeeding for a long time .
Causes :prolonged breastfeeding eventually has some disadvantages,
including limitations on a mother’s schedule and lifestyle, a
baby’s dependence on the breast, pain from first teeth,
critical public opinion and effects on the menstrual cycle ,
lethargic, sleepy, not wanting to eat
Reasons : happens when the child is unsatisfied with breast feeding
(less breast feeding period )
when the child receive less attention from mother
when sucking had become his habbit
or due to unconscious sucking .
Causes : the child may use fingers or pacifiers for long time .this may
cause dental deformations
Vigorous thumb sucking can
have Many effects on the teeth
and mouth. That’s because of
the repetitive pressure the
thumb and sucking places on
the teeth, jawbone, and roof of
■ It may cause any of the following:
■ Overbite, where the front teeth protrude out from the jaw
■ Other bite issues, such as the bottom teeth tipping inward
toward the back of the mouth or an open bite, where the
top and bottom teeth don’t meet when the mouth is closed
■ Changes to the shape of the jaw, which can also affect the
alignment of the teeth and speech patterns, such as the
development of a lisp
■ Sensitivity of the roof of the mouth
■ Feed the child whenever he is hungry
■ Feed the child in natural way breast feeding
■ Never let the habit to be started the practice must be
discontinued at its inception