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• Types of joint
Development of TMJ
Histology of articular surfaces
Innervation of TMJ
Vascularization of TMJ
Muscles of mastication
• The Temporomandibular joint is that
which connects the mandible to the
skull and regulates mandibular
• It is a bicondylar joint in which the
condyles, located at the two ends of
the mandible, function at the same
TYPES OF JOINT
A Joint is an articulation
between two bones.
1. Fibrous Joint: immovable
–Suture - skull
–Gomphosis - teeth
–Syndesmosis – interosseous
–Primary or synchondroses
• Hyaline cartilage at ends of long
–Secondary or symphysis
• Bone-cartilage-fibrous tissuecartilage-bone; symphysis menti
3.Synovial Joint: permits free movement between two
bones; surrounded by capsule enclosing joint cavity
filled with synovial fluid. According to shape of
Craniomandibular articulation – TMJ
Complex joint in the body
Hinging movement – ginglymoid joint
Gliding movements - arthrodial joint
hence TMJ is a complex diarthrodial sliding-ginglymoid
synovial joint, which attaches the mandible to petrous
part of temporal bone of the cranium.
Seperating these two
bones from direct
articulation is the
TMJ – Classified as
articular disc – serve as
non ossified bone that
movements of the
interposed between the
condyle of the mandible
and the glenoid fossa of
the temporal bone.
The articular surface of
the temporal bone has a
posterior concave part –
Anterior convex part –
articular tubercle or
DEVELOPMENT OF TMJ
• The TMJ develops from
between the developing
mandibular condyle below
and the bone above,
• During the 12th week of IU
life ,2 clefts appear in the
the upper and lower joint
• The remaining intervening mesenchyme becomes
the intra – articular disc.
• The joint capsule develops from a condensation of
mesenchyme surrounding the developing joint
• Mandibular fossa is flat at birth and there is no
articular eminence , this becomes prominent only
following the eruption of the decidous dentition.
Bounderies• Anterior aspect articular
• Posterior non articular
fossa Is a part of
temporal squama and is
formed by tympanic
plate which also forms
the anterior bony wall of
external auditory meatus
• As temporal squama and tympanic plate
converge medially on the spine of the sphenoid
bone – intersposed is the bony edge of the roof
of the tympanic cavity –tegmen tympani
• Squamotympannic fissure - fissure between the
temporal squama and tympannic bone
• It is divided medially into anterior part petrosquamous fissure and posterior part
petrotympannic fissure/glaserian fissure.
• Laterally petrotympannic fissure allows passage of
chorda tympani nerve.
• At the posterior border of the fossa – a tubercle or
cone shaped process present laterally between
tympanic bone and fossa.
• This prevents direct impingement of condyle on the
• the medial border of articular fossa also contains a
bony lip which extends into angular spine of
sphenoid bone .
• These two bone processes or lips limit condylar
displacement distally and laterally as well as
A IKAI et al (ajodo 112;634:8)
• Studied the relationship between temporal
component of TMJ – mandibular fossa and articular
eminence) with facial bone structure.
• The angle between the line deepest point of the
fossa- the midpoint of the eminence and FH plane
(middle angle) was negatively correlated only with
ANB angle suggesting that a steeper middle angle of
eminence is related to retrusive maxilla or
Barrel shape –
measuring – 20mm –
• Perpendicular to
ascending ramus of
• Oriented 10 – 30
degrees with frontal
Medial pole more
Articular surface of
Posterior aspect >
• In the frontal view – articular eminence often is
concave and fits roughly to superior surface of
• Bony surface of condyle and articular part of the
temporal bone – covered with dense fibrous
connective tissues with irregular cartilage like cells
• The number of cells increases with age and stress on
• Biconcave oval structure –
intersposed between the
condyle and the temporal
collagenous tissue that is
avascular , hyaline and
devoid of nerve tissues in
the central area but has
vessels and nerves in the
• Divided into 3 regions
in the Saggital plane
• Intermediate zone
• Articular surface
situated in the
thicker medially than
morphology of condyle
and mandibular fossa.
• During movement the disc is
flexible to some extent and
can adapt to the functional
demands of the articular
• The disc maintains its
structural changes occur in
• If these changes occur , the
morphology of the disc can be
irreversibly altered producing
biomechanical changes during
• ATTACHMENTS OF DISC • Retrodiscal tissue highly vascularized
• Superior retrodiscal lamina – elastic fibres
• Inferior retrodiscal lamina - collagenous fibres.
• Remaining – large venous plexus which fills with
blood as condyle moves forward.
Anteriorly–superior and inferior attachments of the
disc– capsular ligament
• Superior attachment –articular surface of temporal
• Inferior attachment – articular surface of condyle
• Composed of collagen fibres
• Between the capsular ligament attachment – superior
lateral pterygoid muscles.
laterally also –
dividing joint into 2
Superior cavity –
surface of disc.
Inferior cavity –
and inferior surface
• The internal surface of the cavities are surrounded by
specialized endothelial cells that form a synovial
• This lining along with a specialized synovial fringe
located at the anterior border of the retrodiscal
tissue produces synovial fluid which fills both the
• TMJ – synovial joint.
Synovial fluid serves 2 purposes
1. Medium for providing metabolic requirements to
the non vascular articular surface of the joint.
2. Lubricant between articular surfaces during
2 mechanisms by which synovial fluid lubricates are
1. Boundary lubrication
2. Weeping lubrication
• Occurs when joint is moved and synovial fluid is
forced from one area of cavity into another.
• The synovial fluid located in the border or recess
areas is forced on the articular surface thus providing
• Weeping lubrication
• Refers to the ability of articular surfaces to absorb a
small amount of synovial fluid
• During function of a joint , forces are created
between the articular surfaces
• These forces drive a small amount of synovial fluid in
and out of articular tissues.
• This is the mechanism by which metabolic exchange
Under compressive forces therefore, a small
amount of synovial fluid is released.
This synovial fluid acts as a lubricant between
articular tissues to prevent sticking,
Weeping lubrication helps eliminate friction in
compressed but not a moving joint.
Only a small amount of friction is eliminated by
Therefore prolonged compressive forces to the
articular surfaces will exhaust this supply.
condyle and the
mandibular fossa are
composed of four
distinct layers or
• Articular zone
• Most superficial layer
• Found adjacent to the joint cavity and forms the
outermost functional surface.
• Made up of dense fibrous connective tissue .
• The collagen fibres are arranged in bundles and
oriented nearly parallel to the articular surface.
• The fibres are tightly packed and are able to
withstand the forces of movement.
• It is less susceptible to the effects of aging and
therefore is less likely to breakdown over time.
• It also has much better ability to repair than does
• The importance of these two factors is significant in
tmj function and dysfunction.
• Proliferative zone
• Undifferentiated mesenchymal tissue –
• This is responsible for the proliferation of articular
cartilage in response to the functional demands
placed on articular surfaces during loading.
• Fibrocartilagenous zone
• Collagen fibrils are arranged in bundles in a crossing
• The fibrocartilage appears in a random orientation
,providing three dimensional network that offers
resistance against compressive and lateral forces.
• Calcified zone
• Made up of chondrocytes and chondroblasts
distributed throughout the articular cartilage.
• In this zone , the chondrocytes become hypertrophic,
die and have their cytoplasm evacuated , forming
bone cells from within the medullary cavity.
• The articular cartilage is composed of chondrocytes
and intercellular matrix.
• The chondrocytes produce collagen , proteoglycans ,
glycoproteins , and enzymes that form the matrix.
• Proteoglycans – complex molecule composed of a
protein core and glycosaminoglycan chains.
• The proteoglycans are connected to a hyaluronic acid
chain , forming proteoglycan aggregates that make
up a great protein of the matrix.
• These aggregates are very hydrophilic and are
intertwined throughout the collagen network .
• Since these aggregates tend to bind water ,the matrix
expands and the tension in the collagen fibrils
counteracts the sweeping pressure of the
• In this way the interstitial fluid contributes to
support joint loading .
• The external pressure resulting from joint loading is
in equilibrium with the internal pressure of the
• As joint loading increases , tissue fluid flows outward
until a new equilibrium is achieved.
• As loading is decreased , fluid is reabsorbed and the
tissue regains its original volume.
• Joint cartilage is nourished predominantly by
diffusion of synovial fluid, which depends on this
pumping action during normal activity.
• The pumping action is the basis for the weeping
lubrication, and this action is thought to be very
important in maintaining healthy articular cartilage.
Vincent .P. Willard Archieves of oral biology (2012) 599606
• Vincent concluded that although the TMJ disc and its
attachments form a seamless complex within the
joint ,a closer look at the biochemical constituents
reveals that these 2 components are distinct .
• While the disc and attachments both contain the
same major constituents ,the relative amounts of
these components vary based on functional
requirements of the tissue
• Disc region have more higher sulfated GAG and
collagen content than the attachment regions.
• In contrast attachment regions –contains more DNA
content than disc region.
INNERVATION OF TMJ
• Most innervation is provided
by the auriculotemporal nerve
as it leaves the mandibular
nerve behind the joint and
ascends laterally and
superiorly to wrap around the
posterior region of the joint
• Additional innervations by –
deep temporal and massetric
VASCULARIZATION OF TMJ
Predominant vessels are
Superficial temporal artery - from the posterior
Middle meningeal artery - from the anterior
Internal maxillary artery – from the inferior
Other important arteries are – the deep auricular
,anterior tympanic and ascending pharyngeal
• The condyle – through marrow spaces by way of the
inferior alveolar artery .
• Ligaments play an important role in protecting the
• The ligaments of the joints are made up of
collagenous connective tissue, which do not stretch.
• They do not enter actively into joint function but
instead act as a passive restraining devices to limit
and restrict border movements.
• Collateral (discal) ligaments
• Attach the medial and lateral
borders of the articular disc
to the poles of the condyle
• Commonely called as discal
ligaments – medial and
• Medial discal ligament –
attaches the medial edge of
the disc to the medial pole of
• Lateral discal ligament –
attaches the lateral edge of
the disc to the lateral pole of
• These ligaments are responsible for dividing the joint
mediolaterally into the superior and inferior joint
• The discal ligaments are true ligaments ,composed of
collagenous connective tissue fibres , therefore they
do not stretch.
• They allow the disc to move passively with the
condyle as it glides anteriorly and posteriorly on the
articular surface of the condyle
• Thus these ligaments are responsible for the hinging
movement of the TMJ , which occurs between the
condyle and the articular disc.
• These ligaments have a vascular supply and are
• Strain on these ligaments produces pain.
• The entire TMJ is
encompassed by the
capsular ligament .
• The fibres of the
capsular ligament are
attached superiorly to
the temporal bone
along the borders of the
articular surface of the
mandibular fossa and
• Inferiorly the fibers of the capsular ligament attach to
the neck of the condyle.
• The capsular ligament -resist any medial, lateral or
inferior forces that tend to separate or dislocate the
• 1 significant function – to encompass the joint thus
retaining the synovial fluid.
• Capsular ligament is well innervated and provides
proprioceptive feedback regarding position and
movement of joint.
The lateral aspect of the
capsular ligament is
reinforced by strong ,
tight fibres – lateral
TM ligament has 2 parts
• Outer oblique portion
• Inner horizontal portion
• Outer portion – extends
from outer surface of the
articular tubercle and
posteroinferiorly to the
outer surface of the
• Inner horizontal portion –
extends from the outer
surface of the articular
tubercle and zygomatic
process posteriorly and
horizontally to the lateral
pole of the condyle and
posterior part of articular
• Oblique portion – resists excessive drooping of the
condyle – limiting the extent of mouth opening.
• During the initial phase of opening ,the condyle can
rotate around a fixed point until the TM ligament
becomes tight as its point of insertion on the neck of
the condyle is rotated posteriorly.
• When the ligament is taut , the neck of the condyle
cannot rotate further .
• If mouth were to be opened wider- the condyle has
to move downward and forward across the articular
• Clinically tested by – closing the mouth and applying
mild posterior force to the chin-jaw easily rotates
until teeth are 20 – 25mm apart after which a
resistance is felt when the jaw is opened wider.
• This resistance is brought about by the tightening of
This unique feature of TM ligament which limits
rotational opening is found only in humans.
• The inner horizontal portion of TM ligament limits
posterior movement of condyle and disc.
• When force applied to the mandible it displaces the
condyle posteriorly , this portion of ligament
becomes tight and prevents the condyle from
moving further into the posterior region of the
• Hence it protects the retrodiscal tissues from trauma
created by posterior displacement of the condyle.
• Also protects the lateral pterygoid muscle from
overextension or overlengthening.
• The effectiveness of TM ligament is demonstrated
during cases of extreme trauma to the mandible.
• In such cases the neck of the condyle is seen to
fracture before the retrodiscal tissues are severed.
• Sphenomandibular ligament
• Accesory ligament of the TMJ
• Arises from the spine of the
sphenoid bone and extends
downwards to a small bone
prominence on the medial
surface of the ramus of the
mandible called the lingula.
• It does not have any
significant limiting effects on
• Stylomandibular ligament
• It arises from the styloid
process and extends
downwards and forward to the
angle and posterior border of
the ramus of the mandible.
• It becomes taut when the
mandible is protruded but is
most relaxed when the
mandible is opened.
• The stylomandibular ligament
therefore limits the excessive
protrusive movements of the
MUSCLES OF MASTICATION
The skeletal components of the body are held
together and moved by the skeletal muscles.
fibers ranging between 10 – 80mm
According to amount of myoglobin
slow/type1 muscle fibers
fast/type ll fibers.
• Slow muscle fibers• Deeper in red color due to higher concentration of
• Capable of slow but sustained contraction
• Well developed aerobic metabolism therefore
resistant to fatigue.
• Fast muscle fibers –
• Whiter due to lower concentrations of myoglobin
• Have fewer mitochondria and rely more on
anaerobic activity for function.
• Capable of quick contraction but fatigue more
• All skeletal muscles contain a mixture of fast and slow
fibers in varying proportions, which reflect the function
of that muscle.
• Muscles that respond quickly – predominantly white
• Muscles for slow continuous activity –
higher concentration of slow fibers
• 4 pairs of muscles – muscles of mastication
3. Medial pterygoid
4. Lateral pterygoid
• Orgin -Rectangular muscle that originates from the
zygomatic arc and extends downward to the lateral
aspect of the lower border of the ramus of the
• Insertion - extends from
the region of the second
molar in the mandible at
the inferior border
posteriorly to include the
• 2 portions –
• superficial portion (fibers
run downward and
• Deep portion (fibers run
predominantly in vertical
Function – elevation of mandible and teeth brought
• Superficial portion – aid in protruding the mandible
• When the mandible is protruded and biting force is
applied ,the fibers of deep portion stabilize the
condyle against the articular eminence.
Acta Odontologica Scandinavica, 2008; 66: 2330
Studies concluded that there is a significant
association between the posterior-to-anterior facial
height ratio and the masseter muscle in children,
indicating that subjects with stronger masseter
muscles have an increased posterior facial height
for a given anterior facial height.
Girls show greater associations than boys between
the masseter muscle and vertical craniofacial
Stavros Kiliaridis et al ,European Journal of
Orthodontics 25 (2003) 259–263
Studied the relationship between thickness of
masseter muscle and width of maxillary dental arch
and results showed that -
• Masseter muscle thickness was greater in older
individuals and in males.
• In the female group, maxillary intermolar width
showed a direct, significant association with
masseter thickness both during contraction and
relaxation i.e. females with thicker masseter muscles
had a wider maxillary dental arch.
• The findings of this study indicate that the functional
capacity of the masticatory muscles may be
considered as one of the factors influencing the
width of the maxillary dental arch.
• Temporal muscle
• Orgin-Large fan shaped
muscle that originates
from the temporal fossa
and lateral surface of
• Divided into 3 distinct
areas according to fiber
direction and ultimate
middle and posterior
• Anterior portion –
• Middle portion obliquely across
lateral aspect of
• Posterior portion –
Function - elevates
teeth brought into
• Contraction of anterior portion – mandible raised
• Contraction of middle portion –elevates and retrudes
• Contraction of posterior portion – elevation and
• Because the angulation of its muscle fibers varies ,
the temporal muscle is capable of co ordinating
closing movements. It thus is a significant
positioning muscle of mandible.
• Clinical examination:
• "Ask the patient to clench their teeth while you
palpate both masseter muscles above the angles of
the jaw and then while you palpate both temporalis
muscles over the temples."
• Medial pterygoid
• Origin - from the
pterygoid fossa and
backward and outward
to insert along the
medial surface of the
masseter muscle ,it
forms a muscular sling
Function – mandible elevated and teeth brought into
- also active in protruding the mandible.
- unilateral contraction brings about a
mediotrusive movement of the mandible
Lateral pterygoid muscle
• Divided into 2 –since their functions are nearly
opposite - inferior lateral pterygoid muscle
superior lateral pterygoid muscle
Inferior lateral pterygoid
• Origin- at the outer surface
of the lateral pterygoid
backward, upward and
outward to its insertion
primarily on the neck of the
• function – when the
inferior right and left lateral
pterygoid muscle contracts
are pulled down their
articular eminences and
mandible is protruded.
• Superior lateral
• Smaller than inferior
temporal surface of the
greater sphenoid wing ,
horizontally , backward
and outward to insert
capsule, the disc and
the neck of the
• While the inferior lateral pterygoid muscle is active
during opening ,the superior lateral pterygoid muscle
remains inactive ,becoming active only in
conjugation with the elevator muscles.
• Function -Superior lateral pterygoid muscle is
especially active during power stroke (movements
that invovle closure of mandible against resistance,
such as chewing or clenching the teeth together)
• Approximately 80% of the fibers that make up both
lateral pterygoid muscles are slow muscle fibers
/type I which suggest that these muscles are
relatively resistant to fatigue and may serve to brace
the condyle for long periods of time without
• Clinical examination of pterygoid muscles
• by forcefully opening the jaw against resistance
• with unilateral lateral pterygoid weakness the jaw
deviates to the ipsilateral side as it opens.
• As a person yawns ,the head is
brought back by contraction of
the posterior cervical muscles ,
which raises the maxillary teeth .
• This simple example shows that
normal functioning of the
masticatory system uses many
more muscles than those of
• Muscles of mastication is only a
part of this complex system
Other accesory muscles are –
• Though not a masticatory
on the function of mandible.
• Divided into 2 –
posterior belly of digastric
anterior belly of digastric
Orgin• Posterior belly –originates from mastoid notch ,
medial to mastoid process – fibers run forward ,
downward and inward to intermediate tendon
attached to hyoid bone.
• Anterior belly - originates at a fossa on the lingual
surface of mandible ,close to the midline – fibers
run downward and backward to insert at the same
intermediate tendon as does the posterior belly.
• Function –
• When the right and left digastric muscle contract and
the hyoid bone fixed by suprahyoid and infrahyoid
muscles ,the mandible is depressed and pulled
backward and teeth are brought out of contact.
• When the mandible is stabilized the digastric muscles
with the suprahyoid and infra hyoid muscles elevate
the hyoid bone ,which is a necessary function for
• The digastric are one of the many muscles that
depress the mandible and raise the hyoid bone.
• STERNOCLEIDO MASTOID MUSCLE
• Large superficial muscles of the
neck that also play a role during
• Orgin –
• the sternal head is tendinous
and arises from the superolateral
part of the front of the
• The clavicular head is
musculotendinous and arises
from the medial one – third of
the superior surface of the
• It passes deep to the sternal head and the 2 heads
blend below the middle of the neck.
Function • When one muscle contracts it turns the chin to
opposite side .
• When both muscles contract together they draw the
head forwards as in eating and in lifting the head
BIOMECHANICS OF TMJ
• The TMJ is an extremely complex joint system -2 TMJ
connected to the same bone.
• TMJ structure can be divided into 2 systems1. Joint system – surrounds the inferior synovial cavity
– condyle and the articular disc(condyle –disc
Since disc is tightly bound to condyle by lateral and
medial discal ligaments, the only physiologic
movement that can occur between these surfaces
is rotation of on the articular surface of condyle .
This joint system responsible for rotational movement
2 Second system is made up of the condyle – disc
complex functioning against the surface of the
• Since the disc is not tightly attached to the
mandibular fossa , free sliding movement is
possible between these surfaces in the superior
• This movement occurs when the mandible is moved
forward – transalation.
• Transalation – occurs between superior surface of
articular disc and mandibular fossa.
• Thus articular disc – non ossified bone – hence TMJ
classified as compound joint.
• The articular surfaces of the joint have no structural
attachment or union-yet contact must be maintained
for joint stability.
• Joint stability-maintained by constant activity of
muscles that pull across the joint.
• Even in resting state ,these muscles are in mild state
of contraction –tonus.
• as muscle activity increases –condyle forced against
disc and disc against mandibular fossa - resulting in
increase in interarticular pressure .
• In the absence of interarticular pressure- articular
surfaces separate and joint dislocates.
• Width of articular disc space varies with
• When pressure is low- closed rest position – disc
• When pressure is high – clenching of teeth – disc
• As interarticular pressure increases – condyle seats
itself on the intermediate zone
• When pressure is decreased –disc space widens and
thicker portion of disc is rotated to fill the space.
• Since anterior and posterior bands are thicker than
intermediate zone – disc rotates anteriorly or
posteriorly to accomplish the task.
• Disc attached posteriorly – retrodiscal tissues which
are highly elastic- hence condyle can move out of
fossa without creating damage to superior retrodiscal
• During mandibular opening –condyle is pulled
forward down the articular eminence ,the superior
retrodiscal lamina becomes increasingly stretched ,
creating increased forces to retract the disc.
• The interarticular pressure and the morphology of
the disk prevent the disc from being overetracted
• Superior retrdiscal lamina –only structure capable of
retracting the disc posteriorly on the condyle.
• Anterior border of articular disc attached to -superior
• Constantly maintained in a mild state of contraction
or tonus –exerts slight anterior and medial force on
• In the resting closed joint position thus anterior and
medial force will normally exceed that of
nonstretched Superior retrodiscal lamina.
• Therfore in the resting closed joint position when the
interarticular pressure is low and disc space widened
–disc will occupy most anterior rotary position on the
condyle and the condyle in contact with intermediate
and posterior zones of the disc.
• This disc relationship is maintained during minor
passive rotational and transalatory mandibular
• As condyle moves more forward – Superior
retrodiscal lamina gets stretched –greater force than
the superior lateral pterygoid – allows disc to be
rotated posteriorly to extent permitted by width of
articular disc space.
At rest condyle rests on posterior band; beginning of translation, it lies over the intermediate zone;
when mouth is fully open, it lies over the anterior band.
Power stroke –
• When resistance is met during mandibular closure
(biting hard food) – interarticular pressure on biting
side is decreased –because force of closure applied
to food not to joint .
• With condyle forward and disc space increased –
tension of Superior Retrodiscal lamina will tend to
retract the disc from a functional position-resulting
in separation of articular surfaces leading to
• To avoid this –superior lateral pterygoid becomes
active during power stroke rotating disc forward on
condyle so thicker posterior border of disc maintains
articular contact-therfore joint stability maintained.
• As teeth pass through the food and approach
intercuspation –interarticular pressure is increased –
disc space decreased – disc rotated posteriorly so
thinner intermediate zone fills the space.
• When the force of closure is discontinued the resting
closed joint position is once again assumed.
• Joseph H. Kronman et al (ajodo 1994;105:257-64.)
• Investigated the site of lateral pterygoid muscle
insertion into the TMJ disk, and the relationship
between that attachment and the disk.
• Results indicated a statistically significant
relationship between functional muscle attachment
and disk displacement.
• the SLP can maintain disk displacement only when it
inserts directly into the disk.
• In cases of normal disk arrangement and condylar
attachment, the muscle may not play a clinically
significant role in disk displacement because disk
attachment at the medial and lateral poles of the
condyle allows the disk to move freely with the
• This movement of the condyle and the disk may
overcome the pull of the SLP when normal disk
attachment is maintained.
• It is impossible to comprehend the fine points of
occlusion without an in depth awareness of the
anatomy ,physiology ,and biomechanics of the TMJ.
• The first requirement for successful occlusal
treatment is stable, comfortable TMJ.
• The jaw joints must be able to accept maximum
loading by the elevator muscles with no signs of
• It is only through an understanding of how the
normal, healthy TMJ functions that we can make
sense out of what is wrong when it isn't functioning
• This understanding of TMJ is foundational to
diagnosis and treatment.
1. Gray’s Anatomy
2. Fundamentals of occlusion and TMJ disorders
3. Grant’s Atlas of Human Anatomy
4. Occlusion – Ash RamfJord
5. Orthodontics Principles and Practice
6. Joseph H. Kronman et al (ajodo 1994;105:257-64.)
7. Stavros Kiliaridis et al ,European Journal of
Orthodontics 25 (2003) 259–263
8. Acta Odontologica Scandinavica, 2008; 66: 2330
9. Vincent .P.Willard Archieves of oral biology (2012)
10. A IKAI et al (ajodo 112;634:8)