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2. CONTENTS
MANDIBULAR MOVEMENTS
ENVELOPE OF MOTION
OCCLUSAL CONTACTS DURING MOVEMENTS
CENTRIC RELATION & CENTRIC OCCLUSION
FUNCTIONAL OCCLUSION
NEUROMUSCULAR SYSTEM
PHYSIOLOGY OF PAIN
MUSCLES
BIOMECHANICS OF TMJ
MASTICATION
DEGLUTITION
SPEECH
APPLIED PHYSIOLOGY
BIBLIOGRAPHY www.indiandentalacademy.com
3. Introduction
It is mandatory to appreciate the
concept of dynamic appreciation since
function can influence the overall pattern
and relationship of the parts, the very
foundations of the stomatognathic system.
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4. STOMATOGNATHIC SYSTEM
The structures involved in speech & in
receiving, chewing & swallowing food
including the oral cavity, teeth, jaws,
pharynx & related structures.
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5. Gnathology
Gnathology - Term given by: McCOLLUM (mid
1920s’)
Science that deals with biology of masticatory
system
• Science dedicated to the study of oral cavity as a
functional unit, in direct relationship to its
morphology, histology, physiology & therapy
including its vital relation with the rest of the body.
Gnathostatic model - A cast of the teeth; trimmed
so that the occlusal plane is in its normal position
in the oral cavity when the cast is set on a plane
surface. Such casts are used in the gnathostatic
technique of orthodontic diagnosiswww.indiandentalacademy.com
6. MANDIBULAR MOVEMENTS
TYPES OF MOVEMENT :
Two types of movements:-
Rotational
Translational
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7. Rotational movement
The process of turning around an axis:
movement of a body about its axis.(Dorland’s
illustrated medical dictionary)
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12. Single-Plane Border Movements
When the mandible moves through the outer range of
motion, reproducible describable limits result, which are
called border movement.
These occur in three different planes:-
Sagittal plane
Horizontal plane
Frontal plane
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13. SAGITTAL PLANE BORDER
AND- FUNCTIONAL MOVEMENTS
Mandibular motion in the sagittal plane have four distinct
movement:-
1. Posterior opening border
2. Anterior opening border
3. Superior contact border
4. Functional
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16. SUPERIOR CONTACT BORDER MOVEMENT
The superior contact border movement is determined by
the characteristics of the occluding surfaces of the
teeth:-
1. The amount of variation between CR and
maximum intercuspation
2. The steepness of the cuspal inclines of the
posterior teeth
3. The amount of vertical and horizontal overlap of
the anterior teeth
4.The lingual morphology of the maxillary anterior
teeth
5. The general interarch relationships of the teeth.
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17. Centric occlusion vs. centric relation
Centric relation: it is the maxillo-mandibular relationship in which
the condyles articulate with the thinnest avascular portion of their
respective disks with the complex in the anterior superior position
against the shapes of the articular eminences, the position is
independent of the tooth contact. (GPT-5)
Also called ligamentous positon or terminal hinge position
If Centric occlusion coincides with the centric relation they appear to
be the same.
Centric relation is bone to bone relation while centric occlusion is
tooth to tooth relation.
Centric occlusion does not coincide with the centric relation in most
of the people with natural teeth.
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18. Centric occlusion: it is
the occlusion of opposing
teeth when mandible is in
centric relation.Also
known as maximal
intercuspal position (ICP)
or habitual occlusion.
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20. Functional occlusion
It is defined as an arrangement of teeth
which will provide the highest efficiency
during all excursive movements of
mandible which are necessary during
function
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21. The slide from CR to intercuspal position is present in approx 90% of
Population & the average distance is 1.25+_ 1 mm according to Sears VH
in 1925
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25. FUNCTIONAL MOVEMENTS
Most functional activities begin at and below the
intercuspal position.
When the mandible is 2 to 4 mm below the intercuspal
position it is at rest.
This is called the clinical rest position. (Young & Meyer)
At this position the muscles have not their least
amount of activity.
The muscles are at their lowest level of activity when the
mandible is 8 mm inferior and 3 mm anterior to the
intercuspal position according to Stallard & Stuart in
1963
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28. Postural effects on functional movements
Final closing stroke as related to
head position.
A
the head upright- the teeth are
elevated directly into maximum
intercuspation from the postural
position
B
With the head raised 45
degrees- the postural position of
the mandible becomes more
posterior. When the teeth
occlude, tooth contacts occur
posterior to the intercuspal
position.
C
With the head angled downward
30 degrees- the postural
position of the mandible
becomes more anterior, When
the teeth occlude, tooth contacts
occur anterior to maximum
intercuspation.
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30. When mandibular
movements are viewed in
the horizontal plane, a
rhomboid-shaped pattern
can be seen
This movement has 4
components:-
1. Left lateral border
2. Continued left lateral
border with protrusion
3. Right lateral border
4. Continued right lateral
border with protrusion
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32. The opposing or the balancing condyle moves down, forward and
inward and makes an angle with the median plane when projected
perpendicularly on the horizontal plane
The lateral shift of the mandible called bennett movement is
measured by the distance of the condyle on working side.
According to Posselt this movement is 1.5 to 3 mm
This angle is called the bennett angle
The lateral movement may have a retrusive or protrusive
component or move straight laterally
The movement may end at any point in 60 degree triangle
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35. Functional movements:
During chewing the range of jaw movements begins some
distance from the maximum Intercuspal position but as the food
is broken down into smaller particle sizes the jaw action comes
closer to the ICP .
Centric relation
Intercuspal position
Area used just before swallowing
Area used in early stage of mastication
End to end position of anterior teeth
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36. FRONTAL (VERTICAL) BORDER
AND FUNCTIONAL MOVEMENTS
In the frontal plane, a shield-
shaped pattern is seen in four
distinct movement components
:-
1. Left lateral superior
border
2. Left lateral opening
border
3. Right lateral superior
border
4. Right lateral opening
border
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41. Occlusal contacts during mandibular
movements
Eccentric movement:
protrusive
laterotrusive
retrusive
Protrusive mandibular movement:-
Occurs when the mandible moves forward from the ICP.
In normal occlusion protrusive contacts occur on the
anterior teeth between the incisal edges and the labial
edges of the mandibular incisors and against the lingual
fossa areas and incisal edges of the maxillary incisors.
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42. Contacts occur between the
distal inclines of the
maxillary teeth and mesial
inclines of the opposing
fossae & marginal ridges
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43. In anterior teeth canines contact and therefore have laterotrusive
contacts, occurs between the labial surfaces and incisal edges of
mandibular canines and lingual fossa and incisal edges of maxillary
canines.
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44. Retrusive
mandibular
movement:-
Occurs when the
mandible moves
posteriorly from the ICP.
Mandibular buccal cusps
move distally across the
opposing maxillary cusps
Contacts occur between
the distal inclines of the
mandibular teeth and the
mesial inclines of the
maxillary teeth.
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45. Neuromuscular system
Neuromuscular: neuron +musculus
It’s a Greek word which pertains to the
nerves and muscles
A highly refined neurological control system
which regulates and coordinates the activity of
the entire muscular system
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46. ANATOMY AND FUNCTIONS OF
NEUROMUSCULAR SYSTEM
Neurological structures:-
Nerve cell bodies in
spinal cord are found in
gray substance of CNS
& outside are grouped
together as ganglia
Neuron
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47. Depending on their location & function neurons are
designated by different terms:
1)Afferent neurons
2) Efferent neuron
3) Interneuron
Nervous impulses are transmitted from one
neuron to another only at a synaptic junction or
synapse.
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48. Graphic depiction of the peripheral nerve input
into the spinal cord
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49. SENSORY RECEPTORS :-
Located in all body tissue and provides
information to the CNS by way of the afferent
neurons.
Some receptors are specific for discomfort and
pain these are called nociceptors.
Receptors that provide information regarding the
position and movement of the mandible and
associated oral structures are called
proprioceptors.
Receptors that carry information regarding the
status of the internal organs are referred to as
interoceptors. www.indiandentalacademy.com
50. The masticatory system uses 4 major types of
sensory receptors:-
1. Muscle spindle
2. Golgi tendon organs
3. Pacinian corpuscles
4. Nociceptors
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51. Muscle spindle
I a, or A alpha-
primary endings or
Annulospiral endings
II, or A beta-
secondary endings or
flower spray endings
Length monitoring
system
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52. 2) Golgi tendon organs:
• They protect the muscle from excessive
or damaging tension
• Tension on the tendons stimulates the
receptors in the golgi tendon organ
therefore the contraction of the muscle
also stimulates the organ.
• Primarily monitor tension
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53. 3)Pacinian corpuscles: -
• Large oval organs made of concentric
lamellae of connective tissue
• These are the structures that serves for the
perception of the movement and firm
pressure.
• These corpuscles are found in the tendons,
joint, priosteum, tendinous insertion, fascia,
and subcutaneous tissue.
• Pressure applied to such tissues deforms
the organ and stimulates the nerve fiber.www.indiandentalacademy.com
54. 4)Nociceptor:
• These are sensory receptors that are stimulated
by injury, and transmit injury information to CNS.
• Nociceptors function to monitor the condition,
position, and movement of the tissues in the
masticatory system.
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55. Reflex action:-
It is a response resulting from a stimulus that
passes as an impulse along the afferent neuron
to a posterior nerve root or its cranial equivalent,
where it is then transmitted to an efferent neuron
leading back to the skeletal muscle
A reflex action may be monosynaptic or
polysynaptic.
monosynaptic reflex
polysynaptic reflexwww.indiandentalacademy.com
56. Two general reflex actions are important in
the masticatory system:-
(1) myotatic reflex
(2) nociceptive reflex.
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59. Clasp knife reflex or autogenic inhibition
Functional significance- protect the overload by preventing damaging
contraction
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60. Mechanism of Orofacial Pain
Pain is the physical sensation associated with
injury or disease
Nociception – noxious stimulus originating from
sensory receptor.
Pain – unpleasant sensation perceived in the
cortex, usually as a result of incoming
nociceptive input
Suffering- how the human reacts to the
perception of pain
Pain behaviour- individuals audible & visible
actions that communicate suffering to others
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61. Types of pain
Differentiate between site & source
1. Primary pain
2. Heterotopic pain
a. Central pain eg brain tumors
b. Projected pain eg. Entrapment of cervical nerve
c. Referred pain eg myocardial infarction
3 clinical rules
Passing from one branch to another in a laminated
manner okeson 1995
Sometimes outside the nerve – moves cephalad not
caudal
In head neck region never crosses the midline
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63. 2) MUSCLES
To propel human skeleton there are 639
muscles,6 billion muscle fibers.
Each fiber has 1000 fibrils…so at 1 time
or another there are 6000 billion fibrils at
work.
Two important physical properties-
Elasticity – F = AE
D L
Contraction
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64. MUSCLE FUNCTION:-
The entire muscle has three potential functions:-
Isotonic contraction (e.g)-The masseter
contracts to elevate the mandible forcing the teeth
through a bolus of food
Isometric contraction- When a number of motor
unit contract opposing a given force the function of
muscle is to stabilize the jaw. This contraction
without shortening is called Isometric contraction
(e.g occurs in the masseter when an object is held
between the teeth (pen).
Controlled relaxation-When stimulation of the
motor unit is discontinued, the fibers of the motor
unit relax & return to their normal length. (e.g).In
the masseter when the mouth opens to accept the
new bolus of food during masticationwww.indiandentalacademy.com
65. Eccentric contraction – at the precise
moment of motor vehicle accident, the
cervical muscles contract to support the
head & resist movement. If the impact is
great sudden changes in inertia of head
causes it to move while the muscles contract
trying to support it. The result is sudden
lengthening of muscles while they are
contracting
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66. Fig. 5. Lateral cephalometric tracings of mandible in open-mouth (1)
and postural resting (2) positions, occlusion (3), and overclosure (4).
Positional influence of mandible on strength of muscle contraction is
shown by the fact that between 2 and 3 the greatest force is created.
Magnitude falls off rapidly between 3 and 4.
Resting length
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67. Muscle strength
Maximum force of muscle when all its
fibers are stimulated to ‘fire’
Summation of contractions= 4 x ‘single
contraction’
Muscle strength is directly proportional to
cross sectional area i.e 3 to 10 kg per
square centimeter of cross section
(Ganong in 1971)
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68. Principles of muscle physiology
Best way to visualize innervaion of muscle is by use of
an electromyogram.
1. All or none law- Sherrington in 1947 pointed out that
individual fibers have no variable contraction status, but
are either relaxed or going into maximum contraction by
virtue of adequate stimulus.
Strength of muscle will depend on- frequency of stimuli &
no. of fibers involved
Not present during muscle fatigue (Merton in 1956)
2. Muscle tonus
3. Resting length
4. Myotatic reflex
5. Reciprocal innervation & inhibition- Sherrington in 1947www.indiandentalacademy.com
69. Reciprocal Innervation:
For the mandible to be elevated by the temporal, medial
pterygoid, or masseter muscles must contract while the
suprahyoid muscles must relax and lengthen.
The neurologic controlling mechanism for the antagonistic
groups is known as reciprocal innervation.
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70. • MOTOR UNIT:
When the neuron are activated the motor end
plate is stimulated to release small amounts of
acetylcholine.
This initiates depolarization of the muscle fibres
and causes the muscle fibers to shorten or
contract.
A single motor neuron may innervate only few
muscle fibers or more (e.g):inferior lateral
pterygoid & masseter
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74. A small change in the TMJ may cause Pathology
PVD & OVD disharmony- Effect on temporalis & masseter
Overclosure with excessive retrusive activity of posterior
temporalis fibers along with masseter
Pterygoid muscle under constant tension causes repeated
stretch reflex & spasms(Graber TM 1969)
This holds the disc anteriorly while condyles push it posteriorly
& upwards. So a click while condyle rides over the posterior
periphery of disc followed by impingement of postauricular
connective tissue
This condition may be mistaken for arthritis.
Shore feels that clicking or popping in TMJ is because of
jumping forward of condyle a fraction of second ahead of disc
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75. Major functions of masticatory system
1. Mastication
2. Swallowing
3. speech
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76. Mastication
Fletcher summarizes his work on masticatory stroke in the adult, using the
six phases outlined by Murphy.
a) The preparatory phase
In which food ingested and positioned by the tongue with in the oral cavity
and the mandible is moved towards chewing side.
b) Food contact
It is characterized by a momentary hesitation in movement. This Fletcher
interpreted to be a pause triggered by sensory receptors concerning the
apparent viscosity of the food and probable trans-articulator pressures
incident to chewing.
c) The crushing phase
If starts with high velocity then slows as the food is crushed and packed.
d) Tooth contact
Accomplished by a slight change in direction but not delay. According to
Murphy all reflex adjustments of the musculature for tooth contact are
completed in the crushing phase before actual contact is made.This was
supported by Moller in 1966
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77. e) The grinding phase
Which coincides with transgression of the
mandibular molars across there maxillary
counterparts and is therefore highly constant from
cycle to cycle. Messerman in 1963 termed this
phase the terminal functional orbit.
Ahelgren noted that during this phase the
bilateral musculature discharge becomes unequal
and asynchronous indicating that the person is
chewing unilaterally.
f) Centric occlusion
When movement of the teeth comes to a definite
and distinct stop at a single terminal point from which
the preparatory phase of next stroke begins.
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79. Although mastication occurs bilaterally, about
78% of observed subjects have a preferred side
where the majority of chewing occurs (pond & Barghi)
This normally is the side with the greatest
number of tooth contacts during lateral glide
Chewing on one side leads to unequal loading of
TMJ
Average length of time for tooth contact during
mastication is 194 msec (Suit,Gibbs & Benz)
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80. Tooth contacts during mastication
Two types-
1. Gliding
2. Single contact
Mean percentage of gliding contacts
during chewing- 60% during grinding
phase & 50 % during opening phase
(Suit,Gibbs & Benz)
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83. When the posterior teeth contact in undesirable
lateral movement, the malocclusion produces an
irregular & less repeatable chewing stroke (Suit,Gibbs & Benz)
Marked difference between chewing strokes of
normal persons & TMJ patients (Mongini, Tempia- Valenta
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84. Andersen 1956- relation of chewing stroke with different
food consistency
According to Gibbs harder the food the more lateral the
closure strokes become
The harder the food the more chewing strokes needed
(Horio & kawamura )
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86. Forces of mastication
Males
Female’s max biting load range- 79- 99 pounds( 35.8-
44.9 kg)
Male’s- 118-142 pounds(53.6- 64.4 kg) by Berkhaus in
1941
The greatest maximum biting force reported is 975
pounds(443 kg) by Gibbs et al in 1985
Molars- 91-198npounds(41.3- 89.8 kg)
Central incisors- 13.2- 23.1 kg) by Howell & Manly in
1948
With age up adolescence (Garner, Kotwal, Worner, Andersen 1944,
1973)
Can be increased with practice & exercise
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87. In a study done by Gibbs et al in 1981 reported
grinding phase of closure stroke averaged 58.7
pounds on posterior teeth- about 36.2 %
subjects maximum biting force
Bakke & mischler in 1991- tooth pain reduces
amount of force used during chewing
According to a study done by Ramjford in 1961
when teeth contact evenly & simultaneously in
the retruded position, the muscles of mastication
have decreased activities & more harmonious
during mastication
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88. Role of tongue in mastication
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89. Deglutition
It is a series of coordinated muscle
contractions that moves a bolus of food
from the oral cavity through the
esophagus to the stomach
It consists of voluntary, involuntary &
reflex muscular activities
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90. Stabilization of mandible is an important part of
swallowing
Somatic swallow- teeth for mandibular stability
The average tooth contact during swallowing lasts
about 683 msec 3x longer than mastication (Suit,Gibbs &
Benz 1975)
Force applied = 66.5 pounds- 9.8 pounds more than
mastication (Suit,Gibbs & Benz 1975)
Infantile or visceral swallow- mandible is braced by
placing tongue forward & between dental arches or
gum pads
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94. • ACTION OF THE VELOPHARYNGEAL VALVE
• ETIOLOGY
o absence of structure (e.g., cleft palate),
o disproportion of structure (e.g.. short palate, deep
nasopharynx, short functional palate).
o neurologic defects (e.g., muscle or central nervous
system)
VELOPHARYNGEAL INCOMPETENCE
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98. Fig. 14. Bar graph illustrating comparative muscle pressures during the
normal swallowing act. Only lateral and medial pterygoid, middle
temporalis, and anterior and posterior masseter fibers show moderate
activity. The remainder demonstrate slight activity.
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99. Fig. 15. Bar graph illustrating comparative muscle pressures
associated with abnormal swallowing. Note heavy mentalis and lip
activity, dominance of posterior temporalis and masseter fibers, and
increased hyoid muscle action. (See Fig. 14.)
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100. Frequency of swallowing
Flanagan et al in 1963 demonstrated
swallowing cycle occurs 590 times during
24 hr period :
146 cycles during eating
394 cycles between meals while awake
50 cycles during sleep
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101. Speech:
Speech is an expression of thoughts by production
of articulate sound, bearing a definite meaning.
It is very sophisticated, autonomous, & unconscious
activity
Its production involves neural, muscular,
mechanical, aerodynamic, acoustic, & auditory
factors
It is one of the highest functions of brain
It is brought about by the coordinated activity of
different parts of brain, particularly the motor &
sensory www.indiandentalacademy.com
102. It occurs when a volume of air is forced from the
lungs by diaphragm through the larynx & the oral
cavity
Vocal cords create sounds with desired pitch &
then precise form assumed by mouth
determines the resonance & exact articulation of
sound
Expiration & inspiration
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103. Mechanism of speech:
Speech depends upon the coordinated activities
of central & peripheral speech apparatus
The central speech apparatus consists of higher
centres- the cortical & subcortical centres
The peripheral speech apparatus includes
larynx, pharynx, mouth, nasal cavities, tongue, &
lips
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104. Speech production; structural & functional
demands:
Controlling airstream that is initiated in the
lungs & passes through the larynx & vocal
cords produces all speech sounds
Adjustments in the airflow contribute to
variations of pitch & intensity of the voice
The structural controls for the speech sounds
are the various articulations or valves made in
pharynx & the oral & the nasal cavities
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105. Each sound is affected by the length, diameter
& elasticity of the vocal tract & by the locations
of constrictors along its length
Because nearly all speech sounds are emitted
from the mouth, the nasopharynx is closed off
from the oropharynx during speech
Closure is performed by an upward lift of the
soft palate
Intimacy of the pharyngeal wall contact, as well
as magnitude of movement by the soft palate,
varies with the nature & sequence of the
speech sounds
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106. As the outgoing air passes through the mouth,
tongue, lips, & mandibular oscillations modify
it.
The tongue has a critical impact on speech
production & needs optimal mobility to lift,
protrude, flatten, forms a groove & contact
adjacent tissues freely.
Jaw and tooth relationship enable the tongue
to articulate against the maxillary teeth or
alveolus.
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107. The 1st
speech sounds are the bilabial sounds
‘m, p & b’
Somewhat later the tongue tip consonants like
‘t’ & ‘d’ appear
The sibilant ‘s’ and ‘z’ sounds which require
that the tongue tip be placed close to but not
against the palate, come later still & the last
speech sound ‘r’ which requires precise
positioning of the posterior tongue, often is not
acquired until age 4-5
Tongue & palate for ‘d’
Articulations of sound
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109. Speech difficulties related to
malocclusion:
s,z (sibilants) - Ant. Open bite, large gap
between incisors
t,d (Linguoalveolar stops) - Irregular
incisors
f,v (Labiodental fricatives) - Skeletal
class III
th,sh,ch (linguodental fricatives) - Anterior
open bite
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110. Lisping
This speech defect involves change of sound of letters and
wards.
Etiology
Main cause is continuity of infantile mode of speech.
If the tongue is moved forward without mandible and lies on
top of lower incisors lisping may result.
Certain malocclusions like openbite, maxillary protrusion,
mandibular retrusion and malaligned tooth also cause lisping.
Stammering
In stammering the child fails to produce any sound for
sometime. These create emotional tension and difficulty in
social adjustment.
Etiology
Hereditary
Due to emotional tension
Lack of balance among two hemispheres of the brain.
Auditory amnesia www.indiandentalacademy.com
114. BUCCINATOR MECHANISMBUCCINATOR MECHANISM
Winders has shown that during mastication & deglutition tongue exerts
2-3 times as much force on dentition as lips & cheeks at 1 time
Sphincter like
Purse string effect
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115. The integrity of the dental arches and the relations
of the teeth to each other within each arch and with
opposing members are the result of the morphogenic
pattern, as modified by the stabilizing and active
functional forces of the muscles.
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118. The tongue has amazingly versatile functional
possibilities by the virtue of the fact that it is
anchored at only one end.
This very freedom permits the tongue to deform
the dental arches when function is abnormal.
When the tongue activity is abnormal, irrespective
of its cause which may be a compensatory
response to abnormal morphogenetic pattern or
retained infantile or visceral swallow, the balance
between the outside and inside force is disturbed
Leads to development of malocclusion like
maxillary anterior protrusion, open bite and
narrowing of maxillary arch.
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119. Mature tongue posture:
During mandibular posture, the dorsum touches
the palate slightly and the tongue tip normally is
at rest in the lingual fossa or at the crevices of
the mandibular incisors.
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121. Fig. 1. Normal
structural relationship.
Note proximity of
tongue and palate;
gentle, un-strained lip
contact; normal
overbite and overjet.
Fig. 20. Sagittal section illustrating Class
II, Division 1 relationship.Note lowered
tongue posture, narrowed buccal dental
segments in maxillary arch, and lower lip
cushioning to lingual aspect of maxillary
incisors during rest and active function. Lip
and tongue team up to accentuate
deformity.www.indiandentalacademy.com
122. Fig. 26. Tongue and lip adaptation to Class III malocclusion. Relatively
functionless lower lip in marked contrast to excessive activity
associated with Class II, Division 1 malocclusion. Lower tongue
position is similar, but with no anterior thrust on deglutition. Greater
upper lip activity is in evidence in the attempt to "close off" during
swallowing.
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123. FRANKEL PHILOSOPHY
Frankel believes that active muscle & tissue mass
has a potential restraining effect on the outward
development of the dental arches
Abnormal perioral musculature exerts a deforming
action that prevents full accomplishment of the
optimal growth & development pattern
Frankel visualizes his vestibular constructions as
“ought to be” matrix that allows the muscles to
exercise & adapt.
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124. CPG & MUSCLE ENGRAM
Within the brainstem is a pool of neurons
that controls rhythmic muscle activities.
This pool of neurons is collectively known
as central pattern generator (CPG)
For precise timing of activity
With the feedback information that allows
CPG to determine the most appropriate &
efficient chewing stroke
It becomes a learned pattern & is
repeated. This learned pattern is muscle
engram
www.indiandentalacademy.com
125. SUMMARY AND CONCLUSION
Before the orthodontist appreciates abnormal
functions of the oro-facial muscles he must have
a knowledge of their normal development and
maturation.
A malocclusion is dynamic balance at that
particular time.
In Orthodontics whenever a patient comes his
teeth will be in the most stable position with the
contiguous structures
As form is related to function, the function
should be corrected for achieving the best form
& stability in the long runwww.indiandentalacademy.com
126. BIBLIOGRAPHY
Jeffrey P.Okeson management of temporomandibular
disorders and occlusion,5th
edition, 29-44,93-107.
Major M. Ash, Sigurd Ramfjord; Occlusion; 4th
edition;164-168.
Aurthr C Gyton, John E Hall; text book of medical
physiology; 9th
edition; W.B. Saunders; pg 803-805,
1048-1050
Robert E Moyers; Handbook of orthodontics; 4th
edition;year book medical publishers; pg 84-85, 173-
174, 203-205, 209-212),
GraberVolume The "three M's": Muscles, Malformation
and Malocclusion,1963 Jun (418 - 450):
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127. T.M.Graber; Thomas Rakosi; Alexander Petrovic;
Dentofacial orthopedic with functional appliance;2nd
edition,
mosby; pg 143-145, 126-130.
T.M.Graber; Bedrich Neumann; Removable orthodontic
appliances; 2nd
edition; W.B.saunders company; pg 145-
154, 167-169.
Chien-Lun Peng, DDS, PhD,a Paul-Georg Jost-Brinkmann,
Priv Doz, Dr med dent,b Noriaki Yoshida, DDS,PhD,c Hsin-
Hua Chou, DDS, PhD,d and Che-Ton Lin, DDS,
PhDe,Comparison of tongue functions between mature and
tongue-thrust swallowing—an ultrasound investigation,
American Journal of Orthodontics and Dentofacial
Orthopedics,Volume 125, Number 5
William R Profitt; contemporary orthodontics; 4th
edition;
mosby Elsevier publication; pg 84-86.
K Sembulingam, Prema Sembulingam; essentials of
medical physiology; 4th
edition; jaypee brothers; pg 244-
246, 847-848.
George A Zarb, Charles L Bolender; prosthodontic
treatment for edentulous patients;12th
edition; Mosby
Elsevier publication; pg 379-385.www.indiandentalacademy.com