ANATOMY,

DEVELOPMENT

&

SURGICAL

ANATOMY

Contents

• INTRODUCTION

• PECULIARITY OF TMJ

• DEVELOPMENT

• COMPONENTS

• MOVEMENTS

• VASCULAR SUPPLY

• INNERVATIONS

• AGE CHANGES

• SURGICALY ANATOMY

• REFERENCES

Introduction

• The most important functions of the temporomandibular

joint (TMJ) are mastication and speech and are of great

interest to dentists, orthodontists, clinicians, and

radiologists.

• The TMJ is a ginglymoarthrodial joint, a term that is

derived from ginglymus, meaning a hinge joint, allowing

motion only backward and forward in one plane, and

arthrodia, meaning a joint of which permits a gliding

motion of the surfaces.

• The right and left TMJ form a bicondylar

articulation and ellipsoid variety of the synovial

joints similar to knee articulation.

• The common features of the synovial joints

exhibited by this joint include a disk, bone, fibrous

capsule, fluid, synovial membrane, and ligaments.

However, the features that differentiate and make

this joint unique are its articular surface covered

by fibrocartilage instead of hyaline cartilage.

Peculiarity of TMJ

1. Bilateral diarthrosis – right & left function together

2. Articular surface covered by fibrocartilage instead of hyaline cartilage

3. Only joint in human body to have a rigid endpoint

of closure that of the teeth making occlusal contact.

4. In contrast to other diarthrodial joints TMJ is last

joint to start develop, in about 7th week in

utero.

5. Develops from two distinct blastema.

6. Non weight bearing joint

7. Depends upon the integrity of the

other structures

Peculiarity of TMJ…….

Components

• Mandibular condyle

• Articular surfaces of Temporal bone

• Capsule

• Articular disc

• Ligaments

• Muscular component

THE MANDIBULAR

CONDYLE

• An ovoid process seated atop a

narrow mandibular neck. It’s the

articulating surface of the

mandible.

• It is convex in all directions but

wider latero-medially (15 to 20

mm) than antero-posteriorly (8 to

10mm).

It has lateral and medial

poles:

• The medial pole is directed

more posteriorly.

• Thus, if the long axes of two

condyles are extended

medially, they meet at

approximately the basion on

the anterior limit of the

foramen magnum, forming

an angle that opens toward

the front ranging from 145°

to 160°

• The lateral pole of the

condyle is rough, bluntly

pointed, and projects only

moderately from the plane

of ramus, while the medial

pole extends sharply inward

from this plane.

• The articular surface lies on

its anterosuperior aspect,

thus facing the posterior

slope of the articular

eminence of the temporal

bone.

• It further continues

medially down and

around the medial pole of

the condyle to face the

entoglenoid process of

the temporal bone where

the jaw is held in an

occluded position.

Cranial Component

or

Articular surfaces of Temporal bone

• The articular surface of the

temporal bone is situated on

the inferior aspect of

temporal squama anterior to

tympanic plate.

• Various anatomical terms of

the joint are elaborated

• (a) Articular eminence:

This is the entire

transverse bony bar that

forms the anterior root of

zygoma. This articular

surface is most heavily

traveled by the condyle

and disk as they ride

forward and backward in

normal jaw function.

(b) Articular tubercle: This is a

small, raised, rough, bony knob

on the outer end of the articular

eminence.

It projects below the level of the

articular surface and serves to

attach the lateral collateral

ligament of the joint.

(c) Preglenoid plane: This is the

slightly hollowed, almost

horizontal, articular surface

continuing anteriorly from the

height of the articular eminence.

(d) Posterior articular ridge and the

postglenoid process:

The posterior part of the mandibular

fossa is an anterior margin of the

petrosquamous suture and is

elevated to form a ridge known

as the posterior articular ridge or

lip.

This ridge increases in height

laterally to form a thickened

cone-shaped prominence called

the post glenoid process

immediately anterior to the

external acoustic meatus.

E: Articular eminence; enp: entogolenoid

process; t:articular tubercle; Co: condyle;

pop: postglenoid process; lb: lateral border

of the mandibular fossa; pep: preglenoid

plane; Gf: glenoid fossa; Cp: condylar

process

(e) Lateral border of the

mandibular fossa: This structur

is usually raised to form a slight

crest joining the articular

tubercle, in front, with the

postglenoid process behind.

(f) Medially the fossa narrows

considerably and is bounded by

a bony wall that is the

entoglenoid process, which

passes slightly medially as the

medial glenoid plane.

• The roof of the mandibular

fossa, which separates it

from the middle cranial

fossa, is always thin and

translucent, even in the

heavy skull.

• This demonstrates that,

although the articular fossa

contains the posterior rim

of the disk and the condyle,

it is not a functionally

stress-bearing part of the

craniomandibular

articulation

Articular Disc

• The articular disc is the most important

anatomic structure of the TMJ.

• It is a biconcave fibrocartilaginous

structure located between the

mandibular condyle and the temporal

bone component of the joint.

• Its functions to accommodate a

hinging action as well as the gliding

actions between the temporal and

mandibular articular bone.

• The articular disc is a roughly

oval, firm, fibrous plate.

1. anterior band = 2 mm in

thickness,

2. posterior band = 3 mm thick,

3. thin in the centre intermediate

band of 1 mm thickness.

More posteriorly there is a

bilaminar or retrodiscal

region.

• It is shaped like a peaked cap that divides the joint into a

larger upper compartment and a smaller lower

compartment.

• Hinging movements take place

in the lower compartment and

gliding movements take place

in the upper compartment.

• The superior surface of the disc - saddle-shaped

to fit into the cranial contour,

• The inferior surface - concave

to fit against the mandibular condyle.

• The disc is attached all around the

joint capsule except for the strong

straps that fix the disc directly to

the medial and lateral condylar

poles, which ensure that the disc

and condyle move together in

protraction and retraction.

• The anterior extension of the

disc is attached to a fibrous

capsule superiorly and

inferiorly.

• In between it gives insertion

to the lateral pterygoid

muscle where the fibrous

capsule is lacking and the

synovial membrane is

supported only by loose

areolar tissue.

• The anterior and posterior

bands have predominantly

transversal running fibers,

while the thin intermediate

zone has anteroposteriorly

oriented fibers.

• Posteriorly, the bilaminar

region consists of two layers

of fibers separated by loose

connective tissue.

• The upper layer or

temporal lamina is

composed of elastin and

is attached to the

postglenoid process,

medially extended

ridge, which is the true

posterior boundary of

the joint. It prevents

slipping of the disc

while yawning.

• The inferior layer of the fibers or inferior lamina curve down

behind the condyle to fuse with the capsule and back of the

condylar neck at the lowest limit of the joint space. It prevents

excessive rotation of the disc over the condyle.

• In between the two layers, an

expansile, soft pad of blood

vessels and nerves are

sandwiched and wrapped in

elastic fibers that aid in

contracting vessels and

retracting disc in recoil of

closing movements.

• The volume of retrodiscal tissue must increase

instantaneously when the condyle translates

anteriorly.

• On sagittal MR imaging, the

disk - biconcave structure with

homogeneous low signal

intensity that is attached

posteriorly to the bilaminar

zone, which demonstrates

intermediate signal intensity.

• The anterior band lies

immediately in front of the

condyle and the junction of the

bilaminar zone, and the disk lies

at the superior part of the

condyle.

• The posterior band

and retrodiskal tissue

are best depicted in

the open-mouth

position.

Fibrous

Capsule

• Thin sleeve of tissue completely surrounding

the joint.

• Extends from the circumference of the

cranial articular surface to the neck of the

mandible.

• The outline – anterolaterally to the articular tubercle,

laterally to the lateral rim of the mandibular

fossa,

posterolaterally to the postglenoid process,

posteriorly to the posterior articular ridge,

medially to the medial margin of the

temporal,

anteriorly it is attached to the preglenoid

plane

The outline of attachment on the

mandibular neck -

• Laterally- the lateral condylar pole but

• Medially - dips below the medial pole.

• On the lateral part of the joint, the capsule

is a well-defined structure that

functionally limits the forward translation

of the condyle.

• Medially and laterally-

blends with the

condylodiscal ligaments.

• This capsule is reinforced more laterally by an

external TMJ ligament, which also limits the

distraction and the posterior movement of the

condyle.

• Anteriorly, the capsule has an

orifice through which the lateral

pterygoid tendon passes. This area

of relative weakness in the

capsular lining becomes a source

of possible herniation of intra-

articular tissues, and this, in part,

may allow forward displacement

of the disk.

• The synovial membrane lining the

capsule covers all the intra-articular

surfaces except the pressure-bearing

fibrocartilage.

• There are four capsular or synovial sulci situated at the posterior

and anterior ends of the upper and lower compartments.

• These sulci change shape during translatory movements, which

requires the synovial membrane to be flexible.

Temporomandibular

Ligaments Complex

Collateral

Ligaments• The ligament on each side of the

jaw is designed in two distinct

layers.

• The wide outer or superficial

layer is usually fan-shaped and

arises from the outer surface of the

articular tubercle and most of the

posterior part of the zygomatic

arch.

• There is often a roughened, raised

bony ridge of attachment on this

area.

• The ligamentous fascicles run obliquely

downward and backward to be inserted on

the back, behind, and below the mandibular

neck.

• Immediately medial to this layer, a narrow

ligamentous band arises from the crest of the

articular tubercle continuously, with

attachment of the outer portion at this site.

• This narrow inner or deep band runs

horizontally back as a flap strap to the lateral

pole of the condyle.

• An upper part of this band continues on to

attach to the back of the disk, lateral to the

condylar pole.

• Medial slippage of the condyle

is prevented medially by the

entoglenoid process and

laterally by the

temporomandibular ligament.

• The outer oblique band becomes taut in the protraction of

the condyle, which accompanies the opening of the jaw,

thereby limiting the inferior distraction of the condyle in

forward gliding and rotational movements, while the inner

horizontal band tightens in retraction of the head of the

mandible, thereby limiting posterior movement of the

condyle .

Sphenomandibular Ligament

• Arises from the angular spine

of the sphenoid and

petrotympanic fissure.

• Runs downward and outward.

• Insert on the lingula of the

mandible.

• The ligament is related –1. Laterally - lateral pterygoidmuscle.

2. posteriorly - auriculotemporal nerve.

3. anteriorly - maxillary artery.

4. Inferiorly - the inferior alveolar nerve

and vessels a lobule of the parotid

gland.

5. Medially - medial pterygoid with the

chorda tympani nerve and the wall of

the pharynx with fat and the

pharyngeal veins intervening.

• The ligament is pierced by

the myelohyoid nerve and

vessels.

• This ligament is passive

during jaw movements,

maintaining relatively the

same degree of tension

during both opening and

closing of the mouth.

Stylomandibular Ligament

• This is a specialized dense,

local concentration of deep

cervical fascia extending from

the apex and being adjacent to

the anterior aspect of the

styloid process and the

stylohyoid ligament to the

mandible’s angle and

posterior border.

• This ligament then extends

forward as a broad fascial

layer covering the inner

surface of the medial

pterygoid muscle.

• The anterior edge of the

ligament is thickened and

sharply defined.

• It is lax when the jaws are closed and slackens

noticeably when the mouth is opened because the

angle of the mandible swings up and back while

the condyle slides downward and forward.

• This ligament becomes tense only in extreme

protrusive movements. Thus, it can be considered

only as an accessory ligament of uncertain

function.

Lubrication of the Joint

• The synovial fluid comes from two sources: first, from

plasma by dialysis, and second, by secretion from type A

and B synoviocytes with a volume of no more than 0.05

ml.

• However, contrast radiography studies have estimated that

the upper compartment could hold approximately 1.2 ml of

fluid without undue pressure being created, while the lower

has a capacity of approximately 0.5 ml.

Synovial fluid……

• It is clear, straw-colored viscous fluid.

• It diffuses out from the rich cappillary network of the

synovial membrane.

Contains:

• Hyaluronic acid which is highly viscous

• May also contain some free cells mostly macrophages.

Functions:

• Lubricant for articulating surfaces.

• Carry nutrients to the avascular tissue of the joint.

• Clear the tissue debris caused by normal wear and tear of

the articulating surfaces.

Muscular Component

• The masticatory muscles surrounding the joint are groups

of muscles that contract and relax in harmony so that the

jaws function properly.

• When the muscles are relaxed and flexible and are not

under stress, they work in harmony with the other parts of

the TMJ complex.

• The muscles of mastication produce all the movements of

the jaw.

• These muscles begin and are fixed on the cranium

extending between the cranium and the mandible on each

side of the head to insert on the mandible.

Teeth and Occlusion

• The way the teeth fit together may affect the TMJ

complex.

• A stable occlusion with good tooth contact and

interdigitation provides maximum support to the muscles

and joint, while poor occlusion (bite relationship) may

cause the muscles to malfunction and ultimately cause

damage to the joint itself.

• Instability of the occlusion can increase the pressure on the

joint, causing damage and degeneration.

VASCULARISATION

• Branches of External Carotid Artery

– Superficial temporal artery

– Deep auricular artery

– Anterior tympanic artery

– Ascending pharyngeal artery

– Maxillary artery

VASCULARISATION

• The Blood supply to TMJ is only Superficial,

i.e. there is no blood supply inside the capsule

• TMJ takes its nourishment from Synovial fluid

Table 1. Muscles of Mastication

Muscle Origin Insertion Nerve Supply Action

Masseter Zygomatic arch

Lateral surface

ramus of

mandible

Mandibular

division of

trigeminal

nerve (V3)

Elevates

mandible to

occlude teeth

TemporalisFloor of

temporal fossa

Coronoid

process of

mandible

Anterior and

superior fibers

elevate

mandible:

posterior fibers

retract

mandible

Lateral

pterygoid

(two heads)

Greater wing of

sphenoid

Lateral

pterygoid plate

Neck of

mandible

Articular disc

Pulls neck of

mandible

forward

Medial

pterygoid

(two heads)

Tuberosity of

maxilla

Lateral

pterygoid plate

Medial surface

of angle of

mandible

Elevates

mandible

Innervations

Movements of synovial joint initiated & effected by muscle coordination.

Achieved in part through sensory innervation.

Hilton’s Law:The principle that the nerve supplying a joint also supplies both the muscles

that move the joint and the skin covering the articular insertion of those

muscles.

Therefore:

Branches of the mandibular division of the fifth cranial nerve supply

the TMJ (auriculotemporal, deep temporal, and masseteric)

Innervations

4 Types of nerve endings:

1. Ruffini’s corpuscles (limited to capsule)

2. Pacini’s corpuscles (limited to capsule)

3. Golgi tendon organs (confined to ligament)

4. Free nerve endings (most abundant)

PROPIOCEPTION

• Ruffini Endings

Position the mandible

• Pacinion Receptors

Accelerate movement during Reflexes

• Golgi tendon Organs

Protection of ligaments Around TMJ

• Free Nerve Endings

Pain receptors

Pacinian Corpuscle

“Onion-like

encapusulated pressure

receptors

Surrounding concentric

lamellae respond to

distortion, generate

action potential in

unmyelinated fiber in

core Bar = 100 microns

Ruffini’s & Golgi Corpuscle

Function:

Ruffini’s = Posture (proprioception), dynamic and static balance

Golgi tendon organ = Static mechanoreception, protection (ligament)

Free nerve endings = Pain (nociception) protection (joint)

HISTOLOGY

OF

ARTICULAR SURFACE OF TMJ

1. The articular zone

• Dense fibrous

connective tissue

• Poor blood supply

• Better ability to

repair

• Good adaption to sliding movement

• Shock absorber

• Less susceptible to the effect of aging

time & breakdown over time.

2. The proliferative

zone

• Mainly cellular

zone

• Undifferentiated

mesenchymal cells

• Proliferation &

regeneration

throughout life

3. The cartilagenous

zone

• Collagen fibers

arranged in criss -

cross pattern of

bundles

• Offers considerable resistance against

compressive & lateral forces

• But becomes thinner with age.

4. The calcified zone

• Deepest zone

• Chondrocytes,

chondroblasts &

osteoblasts

• Active site for remodeling activity as bone

growth proceeds.

RELATIONS

Anteriorly - Mandibular notch

Lateral pterygoid

Masseteric nerve and

artery

• A careful dissection of 16

intact human cadaveric

head specimens revealed

The location of the

masseteric artery was

then determined in

relation to 3 points

process:

1) the anterior-superior

aspect of the condylar

neck = 10.3 mm;

2) the most inferior aspect of

the articular tubercle =

11.4 mm;

3) the inferior aspect of the

sigmoid notch = 3 mm.

RELATIONS

Posteriorly - parotid gland

Superficial temporal vessels

Auriculotemporal nerve

RELATIONS

Laterally –

Skin and fascia

Parotid gland

Temporal branches of facial nerve

Medially - Tympanic plate (separates from ICA)

spine of sphenoid

Auriculotemporal & chorda tympani nerve

middle meningeal artery

maxillary artery

Superiorly –

middle cranial fossa

middle meningeal vessels

Inferiorly –

maxillary

artery

&

vein

Inferiorly –

maxillary

artery

&

vein

Inferiorly –

maxillary

artery

&

vein

Movements

• Rotational / hinge movement in first 20-

25mm of mouth opening

• Translational movement after that when the

mouth is excessively opened.

• Translatory movement – in the superior part of the joint as the

disc and the condyle traverse anteriorly along the inclines of

the anterior tubercle to provide an anterior and inferior

movement of the mandible.

Mouth closed Mouth open

Hinge movement – the inferior portion of the joint between the

head of the condyle and the lower surface of the disc to permit

opening of the mandible.

1. Depression Of Mandible

– Lateral pterygoid

– Digrastric

– Geniohyoid

– Mylohyoid

2. Elevation of Mandible

Temporalis

Masseter

Medial

Pterygoids

3. Protrusion of Mandible

– Lateral Pterygoids

– Medial Pterygoids

4. Retraction of Mandible

Posterior fibres of Temporalis

Age changes of the TMJ:

• Condyle:

– Becomes more flattened

– Fibrous capsule becomes thicker.

– Osteoporosis of underlying bone.

– Thinning or absence of cartilaginous zone.

• Disk:

– Becomes thinner.

– Shows hyalinization and chondroid changes.

• Synovial fold:

– Become fibrotic with thick basement membrane.

• Blood vessels and nerves:

– Walls of blood vessels thickened.

– Nerves decrease in number

These age changes lead to:

-Decrease in the synovial fluid formation

-Impairment of motion due to decrease in the disc

and capsule extensibility

-Decrease the resilience during mastication due to

chondroid changes into collagenous elements

-Dysfunction in older people

Development

• At week 12 of gestation:

– temporal/ glenoid blastema

• Ossifies and becomes glenoid fossa

– condylar blastema

• Becomes the condylar cartilage

• Clefts are formed

– lower joint cavity

– upper joint cavity

1. Primitive

articular disc

2. Upper cleft

3. Lower cleft

4. Temporal

blastema

5. Condylar

blastema

4

33

1. Glenoid fossa

2. Upper joint cavity

3. Articular disc

4. Lower joint cavity

5. Condyle

CLINICAL CONSIDERATIONS

SURGICAL

APPROACHES

TO

TMJ

POST/ RETRO AURICULAR

ENDAURAL

SUBMANDIBULAR

RISDON’S APPROACH

POSTRAMAL /

HIND’S

INCISION

PREAURICULAR

DINGMAN’S INCISION

PREAURICULAR

DINGMAN’S INCISION

Dingman and Grabb (1962)

PREAURICULAR

THOMA’S ANGULATED

INCISION

BLAIR’S INVERVED

HOCKYSTICK INCISION

BLAIR & IVY 1936

BLAIR’S INVERVED

PAPOWICH MODIFICATION

PAPOWICH &

CARNE 1982

• For a wider exposure.

• A question mark shaped skin incision which

avoids main vessels and nerves.

• About 2 cm above the malar arch, the temporalis

fascia splits into 2 parts, which can be easily

identified by fat globules between 2 layers which

form an important landmark.

• In this, temporal facia and superficial temporal

artery are reflected with skin flap. Later helps in

better healing of the flap.

• Under no circumstances should the inferior end

of the skin incision be extended below the lobe

of the ear as it increases the risk of damage to

main trunk of facial nerve. It is particularly

important in children where it may be quite

superficial.

AL-KAYAT & BRAMLEY 1979

• The length of the facial nerve which is visible

to the surgeon is about 1.3 cm.

• In 30 patients study of

precise location of the

temporal branch of the

facial nerve in relation to

the most anterior aspect of

the bony external acoustic

canal was done by

Miloro et al

• mean distance from most posterior ramus of the temporal

branch of the facial nerve to the most anterior aspect of the

external acoustic canal was 2.12 cm ± 0.21 cm (range, 1.68 to

2.49 cm).

• Intraoral approach: It was described by Sear

(1972) for removal of hyperplastic condyles. The

incision commences at the level of upper occlusal

plane and passes downwards and forwards

between the internal and external oblique ridges of

mandible and then forwards as necessary along

mandibular body. Upper end should not be

extended beyond the level of upper molar teeth,

otherwise buccal pad of fat is encountered and

prolapses in the wound decreasing the visibility

Arthroscopy Arthroscopy of the TMJ was first introduced by

Ohnishi in 1975.

1. Superior posterolateral

2. Superior anterolateral

3. Inferior posterolateral

4. Inferior anterolateral

5. Endaural approach

Approaches for the arthroscopic

lysis and lavage of the TMJ

1 = Superior anterolateral approach;

2 = endoaural approach;

3 = superior posterolateral approach;

C= condyle;

G= glenoid fossa.

The superior posterolateral

approach is the most common.

In this technique, the mandible

is distracted downward and

forward, producing a triangular

depression in front of the tragus.

The trocar is inserted into the roof of this depression to

outline the inferior aspect of the glenoid fossa. This provides

visualisation of the superior joint space.

1 = Superior anterolateral approach;

2 = endoaural approach;

3 = superior posterolateral approach;

C= condyle;

G= glenoid fossa.

In the superior anterolateral

approach the trocar is directed

superiorly, posteriorly, and

medially, along the inferior

slope of the articular

eminence. This approach

allows visualisation

of the anterosuperior joint

compartment.

1 = Superior anterolateral approach;

2 = endoaural approach;

3 = superior posterolateral approach;

C= condyle;

G= glenoid fossa.

In the inferior posterolateral

approach, the trocar is

directed against the lateral

posterior surface of the

mandibular head. This

provides visualisation of the

posterior condylar surface and

the inferoposterior synovial

pouch.

1 = Superior anterolateral approach;

2 = endoaural approach;

3 = superior posterolateral approach;

C= condyle;

G= glenoid fossa.

In the inferior anterolateral

approach the trocar is inserted

at a point anterior to the lateral

pole of the condylar head

and immediately below the

articular tubercle. This

technique

allows observation of the

lower anterior synovial pouch.

1 = Superior anterolateral approach;

2 = endoaural approach;

3 = superior posterolateral approach;

C= condyle;

G= glenoid fossa.

The endaural approach is initiated

by entering the posterosuperior

joint space with a trocar from a

point 1 to 1.5 cm

medial to the lateral edge of the

tragus through the anterior

wall of the external auditory

meatus. The trocar is directed

in an anterosuperior and slightly

medial direction toward

the posterior slope of the eminence.

The posterior superior

joint space and medial and lateral

paradiscal troughs can be

examined with this technique

LC = lateral canthus; T = tragus; A = 10mm from the middle of

the tragus and 2mm below the canthotragal line. B = 10mm

further along the canthotragal line and 10mm below it; C= 7mm

anterior from the middle of the tragus and 2mm inferior along

the canthotragal line; and D= 2–3mm in front of point A.

Ankylosis & Kaban’s protocol

• The 7-step protocol consists of

1) Aggressive excision of the fibrous and/or bony ankylotic

mass,

2) Coronoidectomy on the affected side,

3) Coronoidectomy on the contralateral side, if steps 1 and 2

do not result in a maximal incisal opening greater than 35

mm or to the point of dislocation of the unaffected TMJ,

4) Lining of the TMJ with a temporalis myofascial flap or

the native disc, if it can be salvaged,

5) Reconstruction of the ramus condyle unit with either

distraction osteogenesis or costochondral graft

6) Rigid fixation,

7) Early mobilization of the jaw.

• If distraction osteogenesis is used to

reconstruct the ramus condyle unit,

mobilization begins the day of the

operation. In patients who undergo

costochondral graft econstruction,

mobilization begins after 10 days of

maxillomandibular fixation. Finally (step 7),

all patients receive aggressive

physiotherapy

Dislocation

Conclusion

• The temporomandibular joint (TMJ), also known

as the mandibular joint, is an ellipsoid variety of

the right and left synovial joints forming a

bicondylar articulation.

• The common features of the synovial joints

exhibited by this joint include a fibrous capsule, a

disk, synovial membrane, fluid, and tough

adjacent ligaments.

• Not only is the mandible a single bone but the cranium is

also mechanically a single stable component; therefore, the

correct terminology for the joint is the craniomandibular

articulation.

• The term temporomandibular joint is misleading and seems

to only refer to one side when referring to joint function.

• Magnetic resonance imaging has been shown to accurately

delineate the structures of the TMJ and is the best

technique to correlate and compare the TMJ components

such as bone, disk, fluid, capsule, and ligaments with

autopsy specimens.

T H A N K Y

O

U