Funtional analysis 5

FUNCTIONAL ANALYSIS
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Functional Analysis
Functional Analysis is the clinical assessment
of the various functions of the stomatognathic
system to check for their normalcy. If found
abnormal, whether they are causative or
resultant of the malocclusion and whether
they can be eliminated, is assessed.

Clinical importance of functional
analysis
1. To assess how a dysfunction contributes to the
creation &/or aggravation of a malocclusion.
Correction of the dysfunction is integral to the
correction of the malocclusion.
2. Helps to assess the prognosis of treatment. All
functional problems cannot be corrected and in
such cases the orthodontist must realize his limits
and build the occlusion around the existing
functional situation.
3. Helps in selecting the treatment modality (functional
/ fixed) e.g. deep bite correction.

Various diagnostic exercises can be performed
to assess the normalcy of the functioning
of the various components of the
stomatognathic system.
These include:
An assessment of the mandibular position
as determined by the musculature
Examination of TMJ and mandibular
movement
Examination of tongue and its functions
Examination of respiratory function
Examination of lips
Assessment of speech
Dental and occlusal examination

An assessment of the mandibular position as
determined by the musculature.
Under this we measure
1. Postural rest position
2. Inter occlusal clearance
3. Evaluation of the path of closure from rest
to occlusion in:
sagittal plane
vertical plane
transverse plane

Postural rest position
The postural rest position is a relatively
unchanging neuromuscularly derived relationship
of the lower jaw to the upper.It is the position of
the mandible when the elevator and depressor
muscles of the mandible are in a state of minimal
tonic contraction.
Even though it is a relatively unchanging
relationship, it is influenced by head and body
posture as it is influenced by gravity.
Thus in order to standardize the rest position
measurement the following protocol must be
followed.

• The patient is seated upright and relaxed
with the back unsupported.
• The head is oriented with the patient
looking straight ahead at eye level or
looking into his own eyes in the mirror or
head can be positioned with the eye ear
plane (Frankfort horizontal plane)

I. The mandible now has to be brought into
postural rest position. There are several
methods for doing this.
i. Command methods
Phonetic method- The subject is asked to
repeat the selected consonants such as M, C, or
words such as Mississippi, Mysore. After these
phonetic exercises mandible usually returns to
postural rest position.
The patient is instructed not to move his tongue at
this time as the dentist gently parts the lips to
observe the interocclusal space and tongue
position.

ii. Other command methods
The patient is asked to perform selected
functions.having the patients lick the lips and
swallow reduces the desired relationship because
the mandible returns to the postural rest within two
seconds after the exercise.
iii. Non command method
When patient is unaware of the fact that he is being
observed. Careful observations are made as the
patient talks, swallows and turns the head while
being being questioned.

iv. Combined method
The combined method gives the best reproduction of
the protruded rest position or the patient swallows
and then relaxes. The sub mental muscles are then
palpated to assess whether they are relaxed as tone
is increased in opening or closing maneuvers. The
patient is then asked to lick the lips , swallow and
then hold then still. Intra oral examination is
performed by parting the lips gently.

Oral speculum – A. M. Schwarz
Mandibular rest position can be determined using the
rest position speculum. The instrument is placed
laterally between the lips in order to observe the
functional jaw relationship.
However clinical experience has shown that this
instrument interferes with the lip seal and the entire
reflex mechanism of the resting tonus.

Registration of the postural rest position of the
mandible
Direct intra oral method
Calipers can be used to measure the interocclusal space
in canine or incisor area.
Direct extra oral methods- direct caliper measurements
are made on the patients profile by measuring the
distance from nasion to menton both in postural rest and
in habitual occlusion

Indirect extra oral method
Various methods are –
1. Cephalometry - the clinician takes two or three lateral
cephalograms under identical exposure and patient
position conditions –
Postural rest
Initial contact
Full habitual occlusion

Two measurements can be performed on each head
film-one records hinge movement of condyle in the
vertical plane
The second assesses the sliding or translatory action
in the sagittal plane.

EMG
Cinefluorography
Kinesiography – Jankelson 1984
allows the mandibular rest position to
be recorded electronically

Clinical implications of the
interocclusal clearance
Normally at rest the lower canine should be
3mm below the upper in comparison with the
occlusal position. An interocclusal space of
upto 4mm is said to be normal.
A true deep bite is one in which there is a large
interocclusal space caused by infraocclusion
of the posterior segments. It often results
from lateral tongue posture or lateral tongue
thrust habit.

Some class II div 2 cases with adequate lip line are
good examples of true deep overbite. Treatment in
the mixed dentition period requires the elimination of
the environmental factors inhibiting eruption of
posterior teeth. This is a valid and quite attainable
functional appliance treatment objective.

A pseudo deep overbite with a small interocclusal
space already has normal eruption of the posterior
segment teeth further eruption is possible only to a
moderate degree . The deep over bite is combined
with over eruption of the incisors. e.g. class II div2
malocclusion with the lip line and a gummy smile.

The pattern of growth also to be kept in mind.
For e.g. the prognosis is good in a true deep
bite problem with a vertical growth pattern as
the growth is expressed in a vertical direction
eruption of molars is allowed to occur.

Evaluation of the path of closure from postural
rest to occlusion in sagittal plane
Normally the path of closure the path of the mandible from
the rest position to habitual occlusion is primarily rotary
in functional equilibrium and normal occlusion .
In contrast a different path of closure is frequently seen in
class II and class III malocclusions
Class II malocclusions
3 conditions can exists
1. No functional disturbance path of
closure rest to occlusion is straight up
and forward with the hinge movement of
the condyle in the fossa. These are true
class II malocclusions

2. From initial contact to full occlusion
condylar action is both rotary and
translatory back ward and up (posterior
shift )
This functional type of class II
malocclusion appears more severe than
it actually is and presents a good
prognosis for treatment with functional
appliances.
3. From initial contact to full occlusion the
mandible translates down and forward.
This malocclusion is more severe than
it appears with teeth in occlusion.this
variant is least common and it
represents poor prognosis.

In functional malocclusions the elimination of
functional retrusion or protrusion leads to an
improvement in sagittal relationship. This
improvement is a change in the spatial
interrelationship of the of parts and not caused by
growth and development.
In class II malocclusions with normal paths of
closure the intermaxillary relationships still require
alteration but this alteration requires both a
morphologic and a functional change to produce the
desired sagittal correction. The original condylar
action from rest to to occlusion is not changed and
the ultimate condyle-eminence relationship is the
same.

Class III malocclusions
Again three conditions can exist:
1. Straight path of closure - possibility of successful
functional appliance therapy exist only if the
magnitude of the sagittal dysplasia is not too great
and therapy is begun in early mixed dentition.
2. If path of closure is back and up the prognosis is
poorer.

In class III malocclusions with an anterior
displacement that creates an up and forward path
of closure with both rotary and translatory action
of the condyle from postural rest to habitual
occlusion the prognosis is much better. This
condition is called a forced bite or pseudo class III.
It represents a class I skeletal base with functional
protrusion.
Another condition called pseudo forced bite there
is really a skeletal class III and anterior path of
closure occurs as anterior sliding occurs along the
compensated labially tipped maxillary incisors and
lingually tipped mandibular incisors.

Type of
overbite
displacemen
t
Growth
pattern
prognosis
Deep bite Sagittal
relation
True Posterior Horizontal + ++
True Posterior vertical ++ +
True Anterior horizontal + +
True Anterior vertical ++ -
Pseudo Posterior Horizontal - ++
Pseudo Posterior vertical + +
Pseudo Anterior Horizontal - +
Pseudo Anterior vertical - -

Evaluation of the path of closure from
postural rest to habitual occlusion in the
transverse plane.
It consists of observing the path of movement of
mandibular midline as the teeth are brought together
from rest position to habitual occlusion.
Two types of central shifting of mandibular midline can
be differentiated
1. In postural rest midlines are coincident .Midline shift
is seen in occlusal position as the mandible slides
laterally from rest position into a cross bite in
occlusion. This is called latero-occlusion or pseudo
crossbite and is caused by tooth guidance.

It requires eliminating the disturbances in
intercuspation. This can be done by widening
the maxillary arch. Some evidence suggests
that prolonged crossbite relationships can
lead to asymmetric jaw growth if allowed to
continue for a number of years during growth
period.

2.Midline shift present both in occlusal and rest
position
This is seen in true asymmetric facial
skeleton. This is sometime referred to as a
laterognathy.
Successful functional treatment is not
possible. Surgery is the only alternative in
severe cases.

Examination of TMJ and jaw
movements
Clinical significance
Malocclusion and TMJ
TMJ dysfunction symptoms
Examination

Examination of TMJ and mandibular
movements
Examination of TMJ is a very important aspect of
functional analysis for the following reasons:
Early diagnosis of TMJ dysfunction and its elimination
can prevent or eliminate incipient TMJ structural
problems.
Another reason is during functional therapy the
condyle is displaced and dislocated to achieve a
remodeling of the TMJ structures. If TMJ structures
are abnormal at the start the possibilities of
exacerbating the symptoms in the course of
functional therapy exists.

TMJ dysfunctions can arise in the following
manner:
1.malocclusion-parafunction-structural
breakdown
2.trauma
3.inflammation
4.infection
Out of these TMJ dysfunctions arising out of
malocclusion-parafunction are of interest to
the orthodontist.

The relationship between TMJ dysfunction and
malocclusion has been a topic of research
and debate for decades. Various researchers
have come to the conclusion malocclusion
has no bearing on the severity of TMJ
dysfunction. Untreated and treated subjects
have similar prevalence of TMJ symptoms.
On the other hand another set of researchers
alleged that malocclusion can lead to TMJ
symptoms. The present understanding is
depicted below:

Malocclusion Physiologic tolerance
(ability of the person to adapt to the
malocclusion e.g. cuspal
interferences during function)
Increase in
parafunctional
activity
(grinding and
clenching)
Structural
tolerance
(ability of the
muscles, TMJ and
teeth to tolerate
increased forces
created by muscle
hyperactivity)
>
<
Breakdown
(TMJ symptoms)

The symptoms of TMJ dysfunction are :
I. Acute muscle disorders are the most common
symptoms of TMJ disorder. Muscle discomfort
ranges from slight tenderness to extreme pain. The
cause is the increased muscle activity associated
with parafunction leading to muscle fatigue and
leading to vasoconstriction and accumulation of
metabolic waste products in the muscle tissue.
The muscle disorders can lead to restricted
movement of the mandible as the fatigued muscles
cause opening of the mouth difficult without causing
pain.

Spasms of certain masticatory muscles alter the
mandibular position creating an acute
malocclusion. Spasm of the inferior lateral
pterygoid causes this muscle to contract resulting in
disclusion of the posterior teeth on the same side
and premature contact of the anterior teeth on the
opposite side.

II. Joint sounds. These are noises that
originate in the joint during the various
mandibular movements. These are of two
types :
1.clicking-single joint sound of short duration.if it
is loud it is referred to as a ‘pop’.
2.crepitation-rough gravel like sound described
as grating.

Examination of TMJ and related
structures
Examination of the muscles by palpation.
If a patient reports discomfort during palpation of a
specific muscle it can be deduced that the muscle
tissue has been compromised by either trauma or
fatigue. Palpation of the muscle is accomplished
mainly by the palmar surface of the middle finger with
the index finger and forefinger testing the adjacent
areas. Soft but firm pressure is applied to the
designated muscles, the fingers compressing the
adjacent tissues in a small circular motion. A single
firm thrust of 1 or 2 seconds duration is usually better
than several light thrusts.

During palpation the patient is asked whether it hurts
or is just uncomfortable. An attempt is made
therefore not only to identify the affected muscles but
also to classify the degree of pain in each.

When a muscle is palpated muscle tenderness is
classified as:
0-no pain or tenderness reported by the patient
1-uncomfortable(tenderness or sourness)
2-definite discomfort or pain
3-patient shows evasive action or eye tearing or
desire not to have the area palpated again.

A routine neuromuscular examination
includes palpation of the following
muscles:
1.Temporalis- The anterior region is palpated
above the zygomatic arch and anterior to the
TMJ. Fibers of this region run in a vertical
direction. The middle region is palpated
directly above the TMJ and superior to the
zygomatic arch. Fibers in this region run in
an oblique direction across the lateral aspect
of the skull.The posterior region is palpated
above and behind the ear. These fibers run
in a essentially in a horizontal direction.It is
helpful to be positioned behind the patient
and to use the right and the left-hand to
palpate respective muscle areas
simultaneously.

2.medial pterygoid: palpated at their insertions on
the medial surfaces of the mandibular angles. The
finger tips are placed at the inferior borders of the
mandible and lightly rolled medially and superiorly.
Force is then applied to the medial surface of the
angles where the muscles are attached.

3. Masseter: the fingers are placed on the
zygomatic arches (just anterior to the TMJ)
They are then dropped down slightly to the
portion of the masseters attached to the
zygomatic arches just anterior to the joint.
Once this portion (the deep masseter) has
been palpated the fingers drop to the inferior
attachments on the inferior borders of the
ramii.

4.Lateral pterygoid: These muscles are palpated
intra orally or normally approached best approached
by assuming a position in front of the patient. in
areas where the fingers need to be positioned are
very narrow and care must be taken not to approach
too quickly. The index finger is placed in the
maxillary buccal vestibule and the patient is
instructed to partially close,relax the muscles and
position the mandible towards the side being
palpated. The palmer surface of the first finger tip
moves posteriorly superiorly and medially into the
infra temporal fossa area posterior to the maxillary
tuberosity.

Having the patient move the mandible to the side being
palpated that shifts the coronoid process of the mandible
laterally and allows better access to the area. Once the
finger is in proper position force is applied in a medial
posterior and superior direction and the patients response
is recorded.
This technique is widely used to palpate the lateral pterygoid
muscle. It has been shown that the palpation of this
muscle produces a significantly higher incidence of
symptoms than does palpation of any other masticatory
muscle. Yet evidence also suggests that this technique
does not reach the attachment of the lateral pterygoid
muscle to the lateral pterygoid plate.

Functional manipulation of the
masticatory muscles
Since the location of certain muscles makes
palpation difficult, a second method of
evaluating muscle symptoms called functional
manipulation is sometimes used.
This is based on the principle that as a
muscle becomes fatigued and symptomatic
further function elicits pain.
Contracting and stretching exercises are
performed to elicit symptoms.

Contracting Stretching
Medial pterygoid Clenching on teeth or
on a separator
increases pain
Opening mouth
increases pain
Inferior lateral
pterygoid
Protruding against
resistance increases
pain
Clenching on teeth
increases pain,
Clenching on
separator - no pain
Superior lateral
pterygoid
Clenching on teeth or
on a separator
increases pain
Clenching on teeth
or on a separator
increases pain;
opening mouth – no
painwww.indiandentalacademy.com

Maximum incisal distance
Neuromuscular examination is incomplete until the
effect of muscle function on mandibular movement
has been evaluated. Normal range of mandibular
opening when measured interincisally is between 53
and 58 mm. The patient is asked to open slowly until
pain is first felt. This is the maximum comfortable
opening. The patient is next asked to open
maximally. This is the recorded as maximum
opening. Opening less than 40 mm is considered to
be restricted.

Lateral and protrusive movements
The patient is next instructed to move the mandible
laterally. Any lateral movement less than 8 mm is
recorded as a restricted movement. Protrusive
movement is also evaluated in a similar manner.

The path taken by the midline of the mandible during
maximum opening is observed next. In the healthy
masticatory system there is no alteration in the
straight opening pathway. There are two types of
alteration that can occur:
1. Deviation – any shift of the jaw midline during opening that
disappears with continued opening (a return to midline). It is
usually due to a disc interference in one or both joints and is
a result of the condylar movement necessary to get past the
disc during translation. Once the condyle has overcome this
interference, the straight midline path is resumed.
2. Deflection – any shift in the midline to one side that
becomes greater with opening and does not disappear at
maximum opening. This is due to restricted movement in
one joint. restricted movements of the joint can be either
due to:
1. Extracapsular restrictions e.g. due to muscle spasm
2. Intracapsular restrictions e.g. disc interference disorders such
as functionally dislocated discs which limit joint movement

TMJ examination
TMJ palpation-
Pain or tenderness of the TMJ is determined by
digitally palpating the joint in two areas:
1. The finger tips are placed over the lateral aspect of
both the joint areas simultaneously. The finger tips
should feel the lateral poles of the condyles. Medial
force is applied and the patient is asked to report
any symptoms. Synchrony of movement on
opening and closure is checked.

2. Posterior aspect of the joints are palpated by
way of the external auditory meatuses. The
small finger of each hands is placed in the
corresponding ear and force is directed
anteriorly. The patient is asked to report any
symptoms. Synchrony of movement on
opening and closure is checked.

Joint Sounds
Joint sounds can be perceived by placing the
finger tips over the lateral surfaces of the joint
and having the patient open and close. Often
they may be felt by the finger tips. A more
careful examination is performed by placing a
stethoscope over the joint area. The
character of the sounds (clicking or
crepitation) is well as the timing of the sounds
(opening, closing or reciprocal) is recorded.

Examination of the tongue and its
function
Evaluation of the tongue
 Size
 Shape
 Posture
Evaluation of tongue in function
 Swallowing
Cephalometric analysis of tongue

Examination of tongue and its functions
Evaluation of tongue size and shape.
Tongue size can be too large(macroglossia) or too
small (microglossia) relative to the size of the
arches.
Clinical methods of assessing tongue size-
1. The patient is asked to touch the nose tip or chin
with tongue tip.A positive test is considered an
indication of macroglossia.
2. Indentations will be evident on the tongue
periphery.
3. Spaces bw and procumbency of the incisors.
4. Tongue is protruded and there is a resultant open
bite.

5. For a definitive diagnosis of macroglossia
cephalometric analysis is necessary.In the ceph
the tongue mass will fill the entire oral cavity.A
method for ceph evaluation of tongue will be
discussed under ‘tongue posture’.
It should be remembered that true macroglossia
occurs only in certain pathologic conditions such
as myxedema,cretinism,down syndrome and
hypophyseal gigantism.
6. A diagnosis of microglossia is rare .The tongue at
best reaches the lower incisors and the floor of the
mouth is elevated and visible on each side of
tongue.The arch is collapsed with extreme
crowding in the premolar region.

7. Asymmetry of the tongue is more likely to be
functional rather than anatomic. In order to
differentiate between the two conditions the patient
is first asked protrude the tongue and the let it relax
and drape over the lower lip. In each situation the
tongue symmetry is noted.
Functional asymmetries of will change from one
position to another .morphologic asymmetries will
persist in the draped position.

Asymmetries of the tongue has important
clinical implications to dental arch
symmetry,dental midline,maintenance of
treated incisor relationships, etc. Neither
asymmetry is easily corrected and treatment
plan may involve some sort of compromise.

Examination of tongue posture.
The tongue posture is examined clinically with the
mandible in postural rest position .This can be done
by:
1. Casually examining the tongue lip relationship
when the patient is seated in upright position
2. Cephalometric analysis of the tongue posture from
cephalogram taken in rest position and habitual
occlusion.Use if radio opaque coating such as
barium paste on the tongue enhances visualization.

Cephalometric analysis of the tongue
Is1=incisal margin of lower incisors.
Mc=tip of distobuccal cusp of lower 1st
molar.
V=most caudal point on the shadow of the
soft palate or its projection onto the
reference line.
O=bisection point of the line.

Cephalometric analysis of the tongue

Normally in rest position dorsum touches the
palate lightly and the tongue tip normally is at
rest in the lingual fossa or at the crevices of
the mandibular incisors.
The tongue posture varies with the skeletal
morphology.
1.classIII facial skeleton-tongue dorsum tends
to lie below the line of occlusion. Tip lies
forward in rest position.
2.classII facial skeletons-the dorsum is arched
and high. The tip is more retruded.

Two variations from the normal tongue posture can
be seen as per Norman and Tully .(AJO-1956)
1. Nondispersing- the tongue tip is retracted from the
anterior teeth. The tongue is spread laterally between
the posterior teeth.
2. Dispersing-the tongue is protracted and is between
the incisors in resting position. This posture is a
serious problem and is associated with open bite. It
may be be due to
1.infantile postural pattern retained for some unknown
reason.
2. As an adaptation to skeletal open bites
3. As a transitory adaptation to enlarged tonsils,
pharyngyntis, or tonsillitis. In order to avoid the
acutely painful inflamed throat the tongue acquires a
adaptive protruded position.

Clinical significance
1. The first situation represents poor prognosis
and the occlusion must be built around the
existing tongue posture.
2. Surgical correction of the second situation
is often successful, yet literature also
reports relapse. Alleged to be the result the
tongue’s inability to adapt to the new
skeletal morphology.
3. Acquired protracted tongue posture is
readily corrected by resolving the problem
of tonsillitis or pharyngitis.

Evaluation of tongue in function-
swallowing
Swallowing is examined in the following manner .
1. The patient is seated upright with the Frankfort
horizontal parallel to the floor.
2. Observe unnoticed several unconscious swallows.
3. Small amount of tepid water is placed beneath the
patients tongue tip and the patient is asked to
swallow. Mandibular movements, facial muscle
contractions are noted.
4. Hand is placed over the temporal muscle and
swallowing exercise is repeated to feel for
contractions for the muscle.

5. A tongue depressor or mouth mirror is placed on the
lower lip to hold it lightly. While the patient is asked to
swallow.
6. Unconscious swallow may be examined more
specifically as follows.
Some more water is placed in the patents
month and the hand on the temporal
muscle. The patient is asked to swallow for
the last time. After the swallow is
completed, turn away from the patient as if
the examination were over, but retain the
hand against the head. Most patients will in
few moments produce an unconscious
clearing swallow. Unconscious swallowing
behavior is not always the same as on
command, particularly on those patients
who have had some form of tongue thrust
therapy or whose attention has been called
to an abnormal swallow.

Differential diagnosis
Normal infantile swallow- during the normal infantile
swallow, the tongue lies between the gum pads and
the mandible is stabilized by obvious contractions of
the facial muscles. The buccinator muscle is
particularly strong in the infantile swallow as it is in
during infantile nursing. Normal infantile swallow is
seen in the neonate and disappears with the eruption
of the buccal teeth. Elements of both infantile and
mature swallow are seen in early mixed dentition and
is known as transitional swallow. Gradually with the
diminution of buccinator and appearance contraction
of the mandibular elevators mature swallow takes
over.

Normal mature swallow- this characterized be very
little lip and cheek activity and contraction of the
mandibular elevators bringing the teeth into
occlusion.
Simple tongue thrust- there is normal teeth together
swallow bet the tongue thrusts anteriorly in order to
seal a well circumscribed open bite created by
something else usually thumb sucking. Contractions
of the lips, mentalis muscle as well as mandibular
elevators is seen.

Complex tongue thrust- defined as
tongue thrust with teeth apart
swallow. Patients show contraction
of mentalis, lip and facial muscles
and lack of contraction of
mandibular elevators. The open bite
is more diffuse and difficult to define
as the tongue thrusts between all
the teeth. Poor occlusal fit and
instability if intercuspation, because
the intercuspal position is not
repeatedly reinforced during
swallow.

Retained infantile swallow- persistence of
infantile swallow even after eruption of
permanent teeth. Tongue thrusts strongly
between the teeth on all sides. Strong
contraction of the lip and facial muscles,
inexpressive face, low gag thresh hold and
occlude only on one molar in each quadrant.
The prognosis for conditioning such a
primitive reflex is very poor.

Clinical significance of abnormal swallowing
1. Simple tongue thrust corrects itself with correction
of the open bite.
2. Complex tongue thrust requires occlusal
stabilization by orthodontic treatment followed by
tongue training with exercises.
3. Retained infantile swallow is a primitive reflex and
correction is difficult . Poor prognosis.

FUNCTIONAL ANALYSIS
DR. SOUMO MITRA

Functional Analysis is the clinical
assessment of the various functions of
the stomatognathic system to check for
their normalcy. If found abnormal,
whether they are causative or resultant
of the malocclusion and whether they
can be eliminated, is assessed.

 Assessment of the mandibular position as determined by the
musculature.
Postural rest position
Inter occlusal clearance
Evaluation of the path of closure from rest to occlusion in:
sagittal plane
transverse plane
Examination of TMJ and jaw movements
Malocclusion and TMJ symptoms
TMJ dysfunction symptoms-muscle tenderness, sounds, joint pain and range of
motion
Examination
Examination of the tongue
Evaluation of the tongue
 Size
 Shape
 Posture
Evaluation of tongue in function
 Swallowing
Cephalometric analysis of tongue

Evaluation of respiratory function
Examination of respiration
Scope of functional therapy in
respiratory dysfunction

Examination of respiratory function
Research has proved that mouth breathing or
interference in nasal respiration can have important
effects on the craniofacial growth and the positions
of the teeth.
The mechanism most likely taking place is an
alteration in the posture of the head ,tongue and
mandible which alters the pattern of facial growth.
Mouth breathing results in a vertical growth
pattern,open bite predisposition, visceral type
swallow, cross bite, narrowness of the upper arch,
class II division 1 malocclusion and crowding of the
arches.

Methods of examination
1. Study the patient’s breathing unobserved-nasal
breathers usually show the lips touching lightly
during relaxed breathing,whereas mouth-breathers
must keep the lips parted.
2. Ask the patient to take a deep breath- most
respond by inspiring through the mouth, although
an occasional nasal breather will through the nose
with lips lightly closed.

3. Ask the patient to close the lips and take a deep
breath through the nose-
nasal breathers-good reflex control of alar muscles.
alar muscles control the size and shape of the
external nares.in nasal breathers they dilate the
external nares on inspiration.
Mouth breathers do not change the
shape or size of the external nares
and occasionally contract the nasal
orifices on inspiration.
Even nasal breathers with temporary
nasal congestion will
demonstrate reflex alar contraction
and dilation of nares during voluntary
inspiration.

Use of a two surfaced mirror to check the method of
breathing. The mirror is held in between the nostrils
and the upper lip.If the child is a nasal breather the
upper surface will cloud;if a mouth breather the lower
surface will cloud.

4.Cotton butterfly test.
5.Holding a piece of paper under the nostrils helps determine
whether air is escaping from from the nostrils. If paper does
not flutter some obstruction is likely.
6.Holding water in mouth and paper between the lips.
If structural problems are suspected:
adenoids and tonsils can be inspected in the lateral head
film.
Visualization of nasal turbinate,septum through the nostrils.
The diagnosis of nasal breathing is best made by the
otolaryngology and a consultation is recommended if the
problem is suspected.www.indiandentalacademy.com

Scope of functional therapy with
respiratory problems
1. In habitual mouth breathing with little or no respiratory
resistance, functional therapy is indicated:
 Lip exercises-holding a sheet of paper between the
lips to improve lip seal.
 Oral screen with breathing holes.
1. If structural problems occur with excessive adenoid
tissues etc, ENT consultation and possible treatment
should be sought. After the resolution of the problem
orthodontic treatment can begin.
3. If structural conditions are unalterable, functional
appliance therapy cannot be instituted. In such cases
only active fixed appliance therapy is likely to produce
the desired changes. Stability of results is questionable.www.indiandentalacademy.com

Examination of the lips
The lips must be carefully examined as a part of the
functional assessment. The lips should be
examined at rest and during swallow and
mastication.
At rest the lip can be classified as:
1. Only slight contact or a very small gap is evident
between the upper and the lower lips.this is the
normal competent lip.
2. Morphologically inadequate: upper lip is
morphologically short. improvement with lip
exercises is possible only in the early stages.

3. Functionally inadequate lips- lips are adequate in
size but fail to function properly. This occurs due to
an underlying skeletal and dental problem. for e.g.;
in a classII div I malocclusion the lower lip seals
against the lingual surface of the maxillary incisors
whereas the upper lip scarcely functions. Here the
abnormal lip function is secondary to the underlying
skeletal problems.
Spontaneous normal lip functions occur after
retraction and proper positioning of the incisors by
orthodontic , orthopedic or surgical methods. If it
does not a regimen of lip exercise may be
prescribed.

3. Functionally abnormal lips -primary lip dysfunction
a.lower lip sucking or biting- one of the most frequent
abnormal lip functions commonly associated with
tongue thrust swallow.
Also known a mentalis habit or golf ball
appearance of the symphyseal tissue with
excessive mentalis activity. Contact can be
observed between tongue and lower lip during
swallow. Anterior open bite and lingual tipping of the
lower incisors, labial malposition of the upper
incisors occur. Retraction or dehiscence of the labial
gingival tissue overlying the lower incisors can
occur. Lip trap may appear as a result. This occurs
in cases with only slight skeletal discrepancy and
the over jet is due to the dental problem arising
secondarily to the abnormal tongue function.
Functional therapy with lip bumper or modified oral
screen should be given early.

Upper lip biting- is another abnormal lip function
frequently seen in school children. It is a stress relief
syndrome. Tongue function can be normal with hyper
kinetic behavioral activity and abnormal lip habit as
the main pathologic factor.

Speech Analysis
Speech assessment is desirable for orthodontic diagnosis. In
malocclusions with malposed teeth, malposition of the tongue may
also occur impairing normal speech. Usually tongue with its inherent
flexibility is able to compensate for atypical morphologic
relationships.
If abnormal tongue activity is noted during speech it has to be
assessed whether it is adaptive or etiologic to the malocclusion.
Usually it will be found to be adaptive but maturational delays in
development of oral motor coordinations or neural pathologies
affecting oral coordinations may contribute to a malocclusion.
Again learning defects or deafness may produce abnormal speech in
a normally formed mouth.
Morphologic disorders of the tongue (as in ankyloglossia) and
defects of the palate (clefts) can contribute to abnormal speech.

A link between malocclusion and speech
problems is obvious in some patients. In the
presence of severe malocclusion the
production of certain sounds may be difficult
or impossible and effective speech therapy
may require orthodontic treatment.

Speech sound Problem Related malocclusion
S, z (sibilants) Lisp Anterior open bite, large gap
between incisors
T, d (linguoalveolar
stops)
Difficulty in
production
Irregular incisors, especially
lingual position of maxillary
incisors
F, v (labiodental
fricatives)
Distortion Skeletal class III
P, b, m (Bilabial
consonants)
Difficulty in
production
Class II div 1
Th, sh, ch (linguodental
fricatives)
Distortion Anterior open bite

Mastication and malocclusion
Although malocclusion can lead to difficulties in
chewing and impaired masticatory ability, the relation
between morphologic deviations from the ideal
occlusion and impaired function has not been studied
adequately. The orthodontist’s problem is the lack of
an instrument for measuring masticatory activity.
Patients with severe malocclusions often complain
about difficulty in eating. Many patients report that
they have learned to avoid certain foods that they
cannot manage. The same patients usually indicate
that they eat better after treatment and note easy in
mastication as a major benefit of orthodontic
treatment.

Dental examination and occlusal
examination
The dental structures have to be examined carefully
for two reasons:
 Any breakdown in the form of tooth mobility,
pulpitis and tooth wear is indicative of functional
disturbances.
 Any changes in the occlusal relationship that may
contribute to the functional disturbance can be
detected.

Dental examination begins with examination
of teeth and their supportive structures for
any indication of breakdown.
1. Mobility – apart from periodontal disease heavy
occlusal forces (traumatic occlusion) can cause
mobility of teeth. Identified by using two mirror
handles to apply buccal and lingual forces on
each tooth. Any movement greater than 0.5 mm
is noted and graded. Periapical radiograph
should be evaluated for the following signs
which co-relate with the heavy occlusal forces.
1. Widening of periodontal spaces.
2. Condensing osteitis
3. Hypercementosis

2. Pulpitis – when other obvious etiologic factors
such as caries, periodontal disease etc. have
been ruled out, heavy occlusal forces must be
considered as a etiologic factor.

3. Tooth wear – this is the most common sign of functional
disturbance in the masticatory system.
Tooth wear caused by parafunctional activities has to be
differentiated from that caused by functional activity. This is done
by examining the position of the wear facets on the teeth.
Functioning wear should occur very near the fossa areas and
centric cusp tips. These facets occur on the inclines that guide the
mandible in the final stages of mastication.
Tooth wear found during eccentric movements is almost always
due to parafunctional activity. To identify this type of wear it is
necessary to have the patient close on the opposing wear facets
and visualize the mandibular position. If the mandibular position is
close to the intercuspal position it is likely to be functional wear.
However if eccentric position is assumed the cause is more often
parafunctional activity

Occlusal examination
The occlusal contact pattern of teeth is examined in
all possible positions and movement of the
mandible.
1. Centric relation contacts – occlusal examination begins by
locating the centric relation position. The patient lies on his back
relaxed with the chin pointed upwards. The dentist sits behind the
patient, four fingers of each hand are placed on the lower border of
the mandible and the thumbs on the chin. The mandible is guided
by an upward force placed on its lower border and angle while at the
same time the thumb press downwards and backwards on the chin.

The overall force on the mandible is directed so that the
condyle will be seated in the most antero-superior
position braced against the posterior slopes. This is
said to be the most orthopedically stable position of the
condyle in the glenoid fossa. When doing this
maneuver anterior teeth should not move more than
ten mm apart.

Once the centric relation is located the mandible is
arced in a closing movement very slowly until the
first tooth contact occurs very lightly. The patient is
asked to identify the location of these contacts.
The teeth on this side are dried , articulating paper
is positioned between the teeth and the mandible
is again guided and closed until contact is
established. Exercise is repeated to confirm the
contact the exact location is recorded.

2. Centric slide - The patient now holds the
mandible securely on this contact and is
requested to apply force on the teeth. Any
shifting of the mandible is observed. Such a
shifting is normal upto a distance of 1 – 1.5 mm.
3. Protrusive contacts – the patient is asked to
move the mandible from centric occlusion into a
protrusive position. The occlusal contacts are
observed until the mandibular anteriors have
passed completely over the incisal edges of the
maxillary anteriors or a distance of 8 – 10 mm
whichever comes first.

Blue articulation paper is placed between the teeth
as the patient is asked to close and protrude
several times. Red paper is next placed and the
patient closes again and taps in centric occlusion.
The red marks will denote the centric occlusion
contacts and any blue marks left uncovered by the
red will denote protrusive contacts which are then
recorded.

4. Laterotrusive contacts – the patient is asked to
move the mandible until the canines have passed
beyond end to end occlusion or 8 – 10 mm
whichever comes first. The buccal lateral contacts
are visible and the type of guidance is noted which
can be canine guidance, group function on
posterior teeth only. Lingual cusp contacts have to
be located using articulating paper.

5. Mediotrusive contacts – these are perceived by the
neuromuscular system as damaging and there is a
reflex movement the attempts to disengage these
teeth by lowering the condyle ion the fossa. Since
these contacts may play a significant role in
functional disturbance it is important that they be
identified and not masked by the neuromuscular
system. Firm force placed on the mandibular angle
in the superio-medial direction is often adequate to
overcome the neuromuscular protection. Contacts
are identified by placing articulating paper between
the teeth on that side.

Clinical significance of occlusal
examination
The teeth causing functional shifts can be identified
and the appropriate treatment to correct those can
be planned. The rule of thirds is applied to decide
the appropriate treatment.
Rule of thirds:
 The inner inclines of the posterior centric cusps are
divided into three. The opposing cusp tip contact decides
the treatment.
1. When opposing cusp tip contacts on the third closest to
the centric fossa selective grinding is the treatment.
2. Middle third – crown or fixed prosthodontic procedure.
3. Third closest to the cusp tip – orthodontic treatment

Occlusal equilibration is necessary during active
facial growth and occlusal development. Balanced
function is the desired factor in normal occlusal
development since functional crossbite or functional
class II or class III malocclusions may in time create
skeletal complications and tempero-mandibular
dysfunctions.
Occlusal examination should be carried out even
after orthodontic therapy in order to stabilize the
occlusion. This helps in retention of the treatment
results.

Conclusion
how a dysfunction contributes to the creation &/or
aggravation of a malocclusion.
assess the prognosis of treatment. All functional
problems cannot be corrected
selecting the treatment modality

Thank you

Funtional analysis 5

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