TMJ is a ginglymo-diarthroidal joint that is freely mobile with superior and inferior joint spaces separated by articular disc. The type of imaging technique depends upon the clinical problems associated, so either imaging of hard tissue (OSSEOUS) or soft tissue is desired. Certain protocols are to be taken care before the imaging procedure: the amount of diagnostic information available from particular imaging modality. The cost of examination The radiation dose

1. TEMPOROMANDIBULAR
JOINT EXAMINATION
&
ITS IMAGING
MODALITIES
Chetan Basnet
BDS 4th year
Roll No: 02

2. Contents
 Introduction to TMJ
 Examination
i. Clinical Evaluation Of TMJ
ii. Clinical Evaluation Of Muscles of Mastication
iii. Clinical Evaluation Of Cervical Muscles
 Imaging Modalities of TMJ
i. Imaging of osseous structures
ii. Imaging of soft tissues

3. TEMPOROMANDIBULAR JOINT
TMJ is a ginglymo-diarthroidal joint that is freely mobile with
superior and inferior joint spaces separated by articular disc.
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 .

4. Location of TMJ
TMJ are located 1.5 cm anterior to the tragus of ear. The two TMJ
considered together, comprise only one part of the total articulation between
the lower jaw and the skull facial skeleton complex.
The other important contribution is made by the inter-digitation of the
mandibular and maxillary dentition, and function, and health of the joint is
directly related to the condition of the teeth.

5. TMJ
TMJ are the two joints between the mobile mandible and a fixed
temporal bone. Each joint contain two joint spaces which are separated by a
fibro cartilaginous articular disk.
Components of TMJ
1. Glenoid Fossa & Articular Eminence/Protuberance
2. Mandibular Condyle
3. Articular Disk & Capsule
4. Synovial Fluid
5. Discal Ligaments
6. Posterior Attachment or Retrodiscal Tissue or Bilaminar Zone
7. Ligaments associated with TMJ
8. Muscles of Mastication
9. Arterial Supply, Venous Drainage & Sensory Innervation of TMJ

6. Clinical Examination of TMJ
Before moving to the clinical examination of TMJ followings are to be ruled
out :
• The history of presenting illness should comprise of onset and course of
signs and symptoms
• Past history should include the details about arthritis, infections,
degenerating diseases, parotitis, ear disorders, muscular disorders,
trauma, past dental treatment, diet/nutritional adequacy, habits like
clenching, chewing… etc. and the individual lifestyle.
• Then the examination is carried out through the series of
i. Inspection
ii. Palpation
iii. Auscultation

7. QUESTIONS TO BE ASKED:
1. Do you have pain in the face, front of ear and the temple area?
2. Do you get headaches , earaches , neckache , or cheek pain?
3. When is the pain at its worst ?
4. Do you experience pain when using the jaw?
5. Do you experience pain in the teeth?
6. Do you experience joint noises when moving your jaw or chewing?
7. Does your jaw ever lock or get stuck?
8. Does your jaw motion feel restricted?
9. Have you had any jaw injury?
10.Have you had treatment for jaw symptoms? if so , what was the
effect?
11.Do you have any other muscle , bone , or joint problem such as
arthritis?

8. Inspection

9. 1. Inspection
• The face is inspected for any obvious asymmetry, scars,
swelling/ulceration/sinus openings in the pre-auricular area.
• Observed for deviation/deflection of mandible on mouth while opening.
• Assesment of range of mandibular movements: maximum mouth opening
, lateral movement , deviation white opening , protrusive movement

10. • The maximum opening distance
between the incisal edges of
upper and lower incisor is
measured using scale , Boley
gauge or ruler
• Normal opening – 40 to 55 mm
• Normal opening can also be
estimated by patient’s own finger
• Normal : three finger end on end
• Two finger opening reveals
reduction in opening but not
necessarily reduction in function
• One finger opening indicates
reduced function

12. LATERAL RANGE OF MOVEMENT
• Normal lateral range of movement is >7mm
• Measurements are made with teeth slightly seperated,measuring the
displacement of lower midline from maxillary midline.
• Any condition (tumor, muscle spasm, fracture, ankylosis, displaced
meniscus) that prevents the normal translation of one condyle will not
prevent the contralateral condyle from sliding forward normally . The
result is deviation of the chin toward the affected side .

13. Examine the hands for signs of systemic disease (
e .g.,
• Heberden's nodes of osteo-arthrosis, ulnar deviation of rheumatoid
arthritis), which may also involve the TMJ .
• Laboratory tests (e .g., complete blood count, erythrocyte sedimentation
rate, rheumatoid factor, antinuclear antibody, serum uric acid) are helpful
when a systemic cause for TMJ disease is suspected.

14. Palpation

15. 2. Palpation
Palpatory examination of TMJ should include the assessment of
mouth opening, range of mandibular movements, joint tenderness, detection
of click and/or crepitus.
• The TMJ can be palpated by extra-auricular and intra-auricular methods.
• Palpation can be done standing at 10 o’clock or 11 o’clock position

16. Intra-auricular:-
Intra-auricular palpation can be achieved by placing a little finger
inside the external auditory meatus. During mandibular movement the
posterior pole of the condylar head can be palpated with the pulp of the little
finger. Intra-auricular palpation may also be used to elicit capsular
tenderness.

17. Extra-auricular:-
Extra auricular examination of TMJ is done by placing index finger in
the pre-auricular region about 1.5cm medial to the tragus of ear. The lateral
pole of the condyle is accessible during this examination.

18. JOINT SOUNDS
There are 2 types of joint sound to look out for:
 Clicks - single explosive noise of short duration.
 Crepitus - continious 'grating' noise
Auscultate TMJ noises (not routinely done)

19. Clinical Evaluation Of Muscles
of Mastication
Tenderness to muscles of mastication results from stress and fatigue
which are characteristics of temporo-mandibular dysfunction.
The muscles to be examined are:
• Masseter
• Temporalis
• Medial Pterygoid
• Lateral Pterygoid

20. EXAMINATION OF THE MUSCLES
• Functional disorders of the masticatory muscles are probably the most
common TMD complaint of the patients seeking treatment in the dental
office.
• With regard to pain , they are second to odontalgia in terms of frequency.
• They are generally grouped in large category known as “masticatory muscle
disorder”
• As with any pathologic state two major symptoms can be observed:
1.Pain
2.dysfunction

21. PAIN
• Certainly the most common complaint in patients with masticatory muscle
disorder is pain , which may range from slight tenderness to extreme
discomfort.
• Pain felt in muscle tissue is called myalgia.
• It may arise from increased level of muscle use.
• Symptoms are usually associated with a feeling of muscle fatigue and
tightness.
• Some authors suggest it is related to vasoconstriction of relevant nutrient
arteries and accumulation of metabolic waste products in the muscle tissue.
• Within the ischemic area of the muscle , certain algogenic substances (eg
bradykinin , prostaglandins) are released ,causing muscle pain.

22. • Severity of muscle pain is directly related to the extent of the functional
activity.
• Therefore patients always report that pain affects their functional activity.
• The clinician must also remember that , myogenous pain is a type of deep pain
, and if it becomes constant, can produce central excitatory effects.
• Therefore it can reinitiate more muscle pain (i.e. cyclic effect)
• This clinical phenomenon was first described in 1942 as “cyclic muscle spasm” .
• More recently , with the findings that the painful muscles are not truly in
spasm, the term “cyclic muscle pain” was coined.
• Another very common symptom associated with masticatory muscle pain is
headache.

23. DYSFUNCTION
• Usually it is seen as decrease in range of mandibular movement.
• When muscle tissues have been compromised by over-use , any contraction or
stretching increases the pain.
• Therefore to maintain comfort , patient restricts movement within a range that
doesnot increase the pain level.
• Clinically this is seen as inability to open mouth widely.

24. TEMPORALIS MUSCLE
 It is a large fan shaped muscle
that originates from temporal
fossa and lateral surface of
skull.
 Its fibers comes downward
zygomatic arch and lateral
surface of the skull to form a
tendon that inserts into
coronoid process and anterior
border of ascending ramus.

25. It can be divided into three distinct areas:
1. Anterior portion : consists of fibers that are direcrted vertically
2. Middle portion : contains fibers that run obliquely across lateral aspect
of the skull
3. Posterior portion : that are aligned almost horizontally.
When temporal muscle contracts , it elevates mandible.

26. Anterior,
Middle and
Posterior
portions of the
temporalis muscle
should be palpated

27. Temporalis muscle can be seen and readily palpated throughout entire length
and breadth when the patient’s teeth are firmly clenched.

28. MASSETER MUSCLE
ORIGIN:
Superficial portion – anterior 2/3
of lower border of zygomatic
arch
Deep portion – medial surface of
Zygomatic arch
INSERTION:
Lateral surface of ramus,
Coronoid process, and angle of
mandible
FUNCTION:
Elevates mandible, clenches
teeth

29. Palpate multiple areas of
the masseter muscle
As with temporalis muscle, it can
be located when patient’s jaw are
forcibly closed. the body of
masseter can be palpated with
thumb and index finger. index
finger can palpate the entire body
of masseter.

30. MEDIAL PTERYGOID / INTERNAL PTERYGOID
ORIGIN:
Medial surface of lateral pterygoid
plate and tuberosity of maxilla and
can not be palpated
INSERTION:
lower medial surface of ramus of
mandible
FUNCTION:
Elevation and protraction

31. • Anterior part of insertion can be palpated by placing the finger at 45
degrees in the floor if the patients mouth near base of the relaxed tongue.
• The opposite hand can be used to extra-orally to palpate posterior and
inferior portions of insertion.
• Body of the muscle can be palpated by rotating the index finger upwards
against the muscle to near its origin on the tuberosity.

32. LATERAL / EXTERNAL PTERYGOID
ORIGIN:
It originates in two parts:
Superior head from the greater wing
of sphenoid
Inferior head the lateral surface of
the pterygoid plate
INSERTION:
Neck of condyle and articular
disc of TMJ.
FUNCTION:
protraction

33. PALPATION OF LATERAL PTERYGOID MUSCLE
The muscle is palpated by using the little or index finger and placing it
lateral to maxillary tuberosity and medial to coronoid process. The finger
presses upwards and inwards and a painful response can be determined .

34. • Demonstration of the lateral pterygoid’s attachment anterior articular
disc has led to the theory that some anterior disc displacements may be
related to its dysfunction.
• Hyperactivity of the muscle is capable of pulling the disc forward from its
normal position.

35. Clinical Evaluation Of Cervical
Muscles

36. STERNOCLIEDOMASTOID MUSCLE
The sternocleidomastoid passes
obliquely across the side of the neck.
It is thick and narrow at its central
part, but broader and thinner at
either end.
medial or sternal head , which arises
from the upper part of the anterior
surface of the manubrium sterni , and
is directed superiorly, laterally, and
posteriorly.
lateral or clavicular head arises from
the superior border and anterior
surface of the medial third of
the clavicle ; it is directed almost
vertically upward.

37. DIGASTRIC
ORIGIN
anterior belly - digastric fossa
(mandible)
posterior belly - mastoid
process of temporal bone
INSERTION:
Intermediate tendon (hyoid
bone)
ACTION:
When the digastric muscle contracts,
it acts to elevate the hyoid bone.
If the hyoid is being held in place), it
will tend to depress
the mandible (open the mouth).

38. The SCM is effectively palpated on each side of the neck when the patient
moves the head to the contralateral side
PALPATION OF THE MUSCLES

40. Diagnostic Imaging Of TMJ

41. 
The type of imaging technique depends upon the clinical
problems associated, so either imaging of hard tissue (OSSEOUS)
or soft tissue is desired.
Certain protocols are to be taken care before the imaging
procedure:
 the amount of diagnostic information available from particular
imaging modality.
 The cost of examination
 The radiation dose
NOTE:- when selecting the imaging modality the strength and
weakness of each imaging modality should be considered.
Diagnostic Imaging
Of TMJ

42. IMAGING OF TMJ
 OSSEOUES STRUCTURES
1. Panoramic Projection
2. Plain Film Imaging Modalities
3. Conventional Tomography
4. Computed Tomography (CT)
 SOFT TISSSUE STRUCTURES
1. Arthrography
2. Magnetic Resonance Imaging (MRI)

43. IMAGING OF
OSSEOUS STRUCTURES

45. The panoramic projection is often included as a part of examination
as
 it provides an overall view of the teeth and the jaws,
 provides a means of comparison between left and right sides of mandible,
 serves as screening projections to identify certain odontogenic diseases,
 certain disorders that may be source of TMJ symptoms

46. Panoramic machines have specific TMJ programs which are of limited
usefulness.
 Thick image layers
 Oblique view/distorted view of the joints
 Low image quality
However this imaging modality gives a gross osseous change of condyle
such as:-
Asymmetries
Extensive erosions
Large osteophytes
Tumors
Fractures

47. However panoramic projections doesn’t provide information's about
condylar positions or function as the mandible is partly opened or
protruded when radiograph is exposed.
Mild osseous changes may be obscured, and only marked changes in
articular eminence morphology can be seen as a result of super
imposition by the skull base and zygomatic arch.
For these reasons, the panoramic view should not be
considered as a sole in imaging modality and be
supplemented.

48. Plain Film Imaging
Modalities

49. Plain Film Imaging
Modalities
The plain film usually consists of combinations of following projections
and allows visualization in various planes:-
 Transcranial Projections
 Transpharyngeal Projections
 Transorbital Projections
 Submentovertex Projections

50. TRANSCRANIAL PROJECTION

51. TRANSCRANIAL VIEW
It is a view that aids in visualizing the sagittal view of the
lateral aspects of condyle and temporal component. It is
taken in both open and close mouth positions.

52. Film position:
• flat against patients ear
• Centered over TM joint of interest
• Against facial skin parallel to sagittal plane
Position of patient:
head adjusted so sagittal plane is vertical & ala
tragus line parallel to floor
View :
3 positions- open, close, rest mouth

53. Central Ray
1. the central ray is direct at an angle of 250(+ve angulation)
from the opposite side, through the cranium and above
the petrous ridge of the temporal bone.
2. The horizontal angulation can be individually corrected for
the condylar long axis, or an average 200 anterior angle
may be used.
Closed view- size of joint space, position of head of condyle,
shape & condition of glenoid fossa & articular eminence
Open view- range & type of movement
Comparison of both sides

54. Disadvantages :
• Superimposition of ipsi-lateral petrous ridge over the
condylar neck

56. Transcranial projections of the left TMJ. degree of translatory movement
between the closed view (A) and the open view(B)
(A) (B)

57. Transpharyngeal View

58. Transpharyngeal View
(Parma projection, Macqueen-Dell Technique)
This technique provides a sagittal view of the medial pole of the
condyle. It is taken in open mouth position.

59. Film placement-
patient holds the cassette flat against patients ear
Centered over TM joint of interest
Against facial skin parallel to sagittal plane
½ inch anterior to EAM
Position of patient-
Occlusal plane parallel to transverse axis of film-soft parts are in a
line with nasopharynx and joint.
 Patient instructed to inhale slowly through nose, filling of nasopharynx
with air
 Open mouth-condyles move away from base of skull and mandibular
notch is enlarged on opp side.

60. Central ray-
directed from opp side cranially at angle(-5 to -10 degrees)
Beneath the zygomatic arch, through sigmoid notch posteriorly across
pharynx at the condyle
Comparison of both condylar heads

62. Parma modification
Lead lined open ended cone is removed and tube head is brought closer
to skin surface producing magnification of structure reducing superimposition

63. Transorbital Projections
(ZIMMER PROJECTION)

64. It is taken in the open or protruded position and depicts
the entire medial lateral aspect of condyle in frontal plane.
Transorbital Projections

65. Film position-
behind patients head at an angle of 45 degree to sagittal pane
Position of patient-
-sagittal pane vertical
-Canthomeatal line should be 10 degree to the horizontal with head tipped
downwards
Central ray-
-tube head-front of patients face
-directed to joint of interest at an angle of +20 degrees to strike cassette at
right angles

66. Point of entry may be taken as-
- Pupil of the same eye-asking patient to look straight ahead
- Medial canthus of the same eye
Disadvantage :
if the patient cannot open wide, areas of the joint articulating surfaces will
be obscured because of mutual superimposition

68. Condyle seen below articular eminence

69. Submentovertex Projections

70. Submentovertex Projections
A submentovertex projections provides a view of skull base
and condyles in a horizontal plane. It is often used to determine the
angulations of the long axis of the condylar head so for corrected
tomography.

71. Conventional Tomography

72. Conventional Tomography
(CT)
CT provides more information about the 3- Dimensional
shapes and internal structures of the osseous components of
joints by providing detailed image slices and 3D images.
Two types of CT are available:-
1. Conventional CT
2. CBCT
Both modalities can give excellent image of osseous structures,
but only conventional CT can give images of surrounding soft
tissues.

73. ….
Tomography is a radiographic technique that produces multiple
thin image slices, permitting visualization of the osseous structures
essentially free of super-impositions of overlapping.
This technique can provide multiple image slices at right angles
through the joint depicting true condylar position revealing the osseous
changes. However conventional tomography is gradually being replaced by
CONE-BEAM COMPUTED TOMOGRAPHY.

74. NOTE:-
Tomographs typically are exposed in sagittal (lateral)
planes corrected to the condylar long axis, with several image
slices in closed (maximal inter-cuspation) position and usually
one image in maximal open position
It is desirable to supplement sagittal images with coronal
(frontal) tomographs particularly when morphologic
abnormalities or erosive changes of condylar head are
suspected.

75. 
Computed Tomography

76. 
CBCT is the recent technology developed for
angiography in 1982 and subsequently applied to
maxillofacial imaging.
 CBCT has the advantage of reduced patient overdose
compared to medial CT and is likely to replace Conventional
Tomography. In CBCT the patient is scanned in closed
position and low resolution scan done in open or other
positions.

77. 
Data from the axial slices can be manipulated to
produce corrected lateral and frontal images of the
TMJ. PANOROMIC and 3-D reformatted images can
also be produced. These are useful for assessing
osseous deformities of the jaws or surrounding
structures.
NOTE:- Conventional and CBCT can not produce accurate
images of the articular disk.

78. 
 Three-dimensional shape and internal structure of the
osseous components
 Surrounding soft tissue
 Both axial & coronal images
 Reformat images in sagittal plane
 Not diagnostic for disk
…

79. 
Indications:
 Extent of ankylosis
 neoplasms-bone involvement
 Complex fractures
 Complications -polytetrafluoroethylene or silicon sheet
implants -erosions into the middle cranial fossa
 Heterotopic bone growth

80. DIRECT SAGITTAL CT
SCANS
3 scans/joint-closed, half,
open-2mm slice thickness
Neck bent- 45 to 55 degree
so that the plane of ramus
is parallel to the imaging
plane

82. Soft Tissue Structures
Imaging

83. Soft tissue imaging is indicated when the TMJ pain and
dysfunction are present and when clinical findings suggest disk
displacement along with symptoms that arte unresponsive to
conservative therapy. Imaging should be prescribed only when the
anticipated results are expected to influence the treatment plan.
The imaging modalities for soft tissues are:
1. Arthrography
2. Magnetic Resonance Imaging (MRI)

84. Arthrography

85. Arthrography
Norgaard (1940)
It is a technique in which an indirect image of the disk is
obtained by injecting a radiopaque contrast agent into the joint spaces
under fluoroscopic guidance.
However MRI has replaced Arthrography in todays
context and is now the imaging technique of choice for soft
tissues.

86. Indications:
Position and function of disk -pain and dysfunction-long
standing
History of locking-persistent
Perforations of the disk and retrodiskal tissue.
Joint dynamics
Disc displacement-ant/anteromedial

87. Contraindications:
Infections in the preauricular region.
Patients allergic to contrast media.
Patients with bleeding disorders and on anticoagulant therapy

88. Contrast Media Arthroscopes
Arthroscopic sheath
Arthroscopic biopsy

89. • Vascular injury
• Extravasation of irrigation
fluid into the surrounding
tissue
• Broken instruments in the
joint
• Intracranial damage
• Infection
• Nerve injury
Complications

90. MAGNETIC RESONANCE
IMAGING
(MRI)

91.  Uses Magnetic field and radiofrequency pulses
 Tissue with greater water content emit a higher signal
 Bilateral dual surface coils- 0.5 to 2 tesla-Improve image
resolution
 MRI produces excellent image qualities so is the principle
imaging choice for soft tissue.
Oblique sagittal/oblique coronal scans with t1, t2
Closed mouth, partially open and fully open positions

92.  images in the sagittal and coronal planes without repositioning
the patient
 T1-weighted images best –osseous & diskal tissues
 T2-weighted images- inflammation and joint effusion.
 Motion MRI studies-during opening and closing the patient
open in a series of stepped distances and using rapid image
acquisition. ("fast scan ")

93. Disk is of low signal intensity (dark grey or black) and can be
distinguished from surrounding tissue that has high signal
intensity.
Posterior disk attachment (PDA) shows higher than the disk
and the junction between the posterior band of the disk and
PDA is distinct.
Medial disk displacements-best seen

94. NOTE:-
It is contraindicated in patient who are pregnant or have
pacemakers, intra-cranial vascular clips, or metal particles
in vascular structures. Some patients may be unable to
tolerate the procedure due to claustrophobia( or inability
to remain motionless.)

95. MRI of a normal TMJ.
A. Closed view showing the condyle and temporal component. The biconcave disk is
located with its posterior band (arrow) over the condyle.
B. Coronal image showing the osseous components and disk (arrows) superior to
the condyle.
A. B.

96. This sagittal MR image shows anterior disk displacement in the
closed mouth position. Disc is deformed

97. Advantages of CT
 Direct delineation of
bony structures-
surgical anatomy
 Reconstruction in all
planes
 Some soft tissues-
lateral pterygoid
muscle
 3-D images from
any angle
 Disadvantages-
-high radiation
exposure
-soft tissues cant be
appreciated
Advantages of MRI
 Soft tissues-esp disk
and its association
 Information in short
acquisition time
 Disadvatages-
-expensive
-claustophobia

98. References
 Oral Radiology- 6th edition
Stuart C. White, Michael J. Pharoah
 Burket’s Oral Medicine – 11th edition
Giclk , Ship, Greenberg,
 Textbook Of Oral Medicine Oral Diagnosis and Oral Radiology- 2nd
edition
Ravikiran Ongole, Praveen B N
 Other Sources- Internet, Google, Wikepedia

99. THANK YOU