The document provides an extensive overview of the temporomandibular joint (TMJ), focusing on its anatomy, various imaging modalities, and the techniques used for diagnosis and treatment of TMJ disorders. It discusses conventional radiography methods, including orthopantomograms and transcranial views, as well as advanced imaging techniques like CT and MRI, their indications, advantages, and limitations. Furthermore, it highlights the role of ultrasonography and arthrography in TMJ evaluation, emphasizing the need for accurate imaging to address complex pathologies associated with the joint.

2. CONTENTS
 Introduction
 Radiographic anatomy
 Types of imaging modalities
 References
 Conclusion

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

4. Radiographic
anatomy
 Extreme aspects of condyle – medial & lateral
poles
 Long axis of condyle is slightly rotated on the
condylar neck such that the medial pole is
angled posteriorly- angle of 15 to 33 degrees
with the sagittal plane.
 Two condylar axes typically intersect near the
anterior border of the foramen magnum-
submentovertex projection

5.  Complete calcification of TMJ-20 yrs
 No cortical border in children-radiograph
 Mandibular fossa & articular eminence-4 yrs-
mature shape
 Pneumatization-sometimes
 Radiographic joint space-radiolucent area
between the condyle and temporal
component

6. CONVENTIONAL RADIOGRAPHY
Orthopantomogram:
Conventional OPG machine orients the x ray
beam obliquely through the condyle.
Limited view of the fossa condyle relationship.

7. The patient’s head is displaced forward/ the
alignment of the source is altered so that the central
beam is oriented along the long axis of the condyle.
 Condyles - gross osseous changes, extensive
erosions, growths or fractures
 No information about condylar position or function
(Mandible is partly opened and protruded when this
Radiograph is exposed)

8. Dental panoramic tomograph
Indications-
 TMJ dysfunction syndrome
 Disease within joint
 Pathology-condylar heads
 Fracture of condylar head & neck
 Condylar hypo/hyperplasia

9.  Advanced high condylar panoramic
radiography
 Sagittal (lateral) plane ->several image
slices
 Closed (maximal intercuspation)
position & in maximal open position
 Condylar long axis with respect to the
midsagittal plane –submentovertex
 patient's head is rotated to an angle,
permitting alignment of image slices
perpendicular to the condylar long axis.

10. A B C
Corrected lateral (sagittal) tomograms. A represents a lateral
image slice, B represents a medial image slice of the same
joint. Condyle appears centered in the lateral image and
retruded in the medial image. C, Open view showing the
degree of condyle translation during mandibular opening.

11.  Minimizes geometric distortion of joint-
condylar position.
 Corrected tomographic technique-not
available
 20-degree head rotation toward the side
of interest is superior to image slices
parallel to the midsagittal plane.
 Bite block

12. Coronal tomographs
 Maximal open or protruded position
 Condyle to the summit of the articular
eminence
 Free of superimposition of the posterior
slope of eminence.
 Entire condylar head is visible in the
mediolateral plane

13. CONVENTIONAL RADIOGRAPHS
 TRANSCRANIAL VIEW
INDICATION AREA OF JOINT
SEEN
TMJ pain Lateral aspect of:
dysfunction Glenoid fossa
syndrome
Internal Articular eminence
derangement
Joint space
Range of
movement in joints
Condylar head

14.  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

15. Central ray
 A) Postauricular/ Lindblom Technique
-1/2 inch behind and 2 inch above auditory
meatus
-central ray should be directed posteriorly so it
passes along long axis of condyle.
 B) Grewcock approach
-central ray passes through a point 2 inches
above ext. auditory meatus.
 C) Gill’s approach
- ½ inch anterior and 2 inch above EAM

16.  Central ray aimed downwards at 25 degree to
the horizontal, across the cranium, centering
through TMJ of interest
 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
Disadvantages :
 Superimposition of ipsilateral petrous ridge
over the condylar neck

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

19. TRANSPHARYNGEAL
VIEW/Infracranial/McQueen
Dell
INDICATION AREA OF JOINT SEEN
Tmj pain dysfunction Lateral view:
syndrome Condylar head & neck
Osteoarthritis &
rheumatoid arthritis Articular surface
Pathology-condylar
head-cyst & tumor
Fracture of neck &
condyle

20.  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

21.  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.
 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

23. TRANSPHARYNGEAL
VIEW

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

25. TRANSORBITAL (ZIMMER PROJECTION)
INDICATION AREA OF JOINT SEEN
Trauma Ant view of TMJ
Fracture cases Medial displacement of
fractured condyle
Fracture of neck of
condyle

26.  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

27. 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

28. Condyle seen below articular
eminence

29. Reverse towne’s
INDICATION AREAS OF JOINT SEEN
Articular surface of Posterior view of both
condyles and disease condylar head and neck
within joint
Fracture of condylar
head & neck,
intracapsular fracture
Condylar
hypo/hyperplasia

30.  Film position-cassette placed perpendicular
to the floor
 Long axis of cassette placed vertically
 Position of patient-
-sagittal plane vertical & perpendicular to film
-lips are centered on the film
-only forehead should touch the film
-mouth wide open
-angle of negative 30 degrees to film
 Central ray-directed midsagittal plane at the
level of mandible and perpendicular to film

31. Forehead –nose
position
Appreciation of
condyle on left
side
REVERSE
TOWNE’S (Eric
Whaites)

32. Towne’s view/anteroposterior
view
 Observe occipital area of skull
 Neck of condylar process
 Film position-cassette perpendicular to floor,
long axis-vertically
 Position of patient- back of patients head
touching film. canthomeatal line
perpendicular to film
 Central ray-30 degree to canthomeatal line &
passes it at a point b/n external auditory
canals

33. TOWNE’S VIEW

34. ULTRASONOGRAPHY
Ultrasonography was described to be an
alternative method in the imaging of the TMJ
by Stefanoff et al. (1992).
High resolution ultrasonography was used to
show satisfying results in further studies by
Emshoff et al. (2002) and Jank et al. (2002).

35. MARCELLO MELIS et al. Use of ultrasonography for the
diagnosis of temporomandibular joint disorders: A review .
Am J Dent2007;20:73-78
 Noninvasive and inexpensive Advantages
 Disc displacement and joint effusion
 Scarce accessibility of the medial part of the
TMJ structures Disadvant
ages
 Need for trained and calibrated operators

36. Positioning of the transducer and consequent visualization of the
temporomandibular joint (TMJ). A. Horizontal positioning,
transverse image of the TMJ. B. Vertical positioning,
coronal/sagittal image of the TMJ (depending on the angulation of
the transducer).

37. TMJ ARTHROGRAPHY
 Norgaard (1940)
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

38. Therapeutic :
To delineate loose bodies in the joint spaces
Diagnostic aspiration of joint fluid.
Intraarticular injections of steroids
 Contraindications:
Infections in the preauricular region.
Patients allergic to contrast media.
Patients with bleeding disorders and on
anticoagulant therapy

39. Disk is anteriorly positioned and thickened
Techniques
Single contrast – lower compartment
arthrography is most commonly done
Double contrast – contrast medium into
the lower compartment and injection of
air into the upper compartment.

40. STEPS
 Contrast media – non ionic agents such as
iopamidol-370,iodohexol-350
 Fluoroscopy aids in accurate positioning of
needle
 Primary record-video-allows imaging of
joint compartments as they move
 Only lateral parts seen

41.  Medial aspect of joint-thin section
multidirectional hypocycloidal tomography
 5-6 slides ,2-3 mm apart, patient mouth open
and closed
 If further info-contrast –upper joint space-
repeat investigation

42. ARTHROSCOPY
Contraindications
Absolute
Bony ankylosis.
Advanced resorption of the glenoid fossa.
Infection around the joint area.
Malignant tumors.
Relative
Patients at increased risk of hemorrhage.
Patients at increased risk for infection.

43. Arthroscopes:
Types
Classic thin lens
Rod lens
Coherent bundle
Graded refractory index system
Field of vision is increased by rotating the
instrument.

44. EQUIPMENT
Arthroscopic sheath :
 Fits on the
arthroscope- protects
the tip.
 Used for irrigation ,
suction of any loose
fragment.
 Light source : xenon
arc illuminator.
 T.V camera and video.
 Biopsy forceps

45. TECHNIQUE
Three primary approaches to the upper
compartment
Lateral posterior
Lateral anterior
End aural

46. Areas visualized
 Loss of well defined boundary b/w PDA
and posterior part of the disk seen in
degenerative changes : Osteoarthritis
 elongation of the PDA
 Medial capsule

47. Arthroscopic biopsy
Two approaches
1.Blind technique.
2.Direct vision technique.
triangulation method
double channel sheath method.

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

49. Computed Tomography (CT)
 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

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

51. 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

53. Panoramic radiograph displaying
duplication of both condyles.
Coronal computed tomography
GUNDUZ, K.; AVSEVER, H.
& KARACAYLI, U. Bilateral
bifid condylar process. Int.
J. Morphol., 28(3):941-944,
2010.

54. MAGNETIC RESONSNCE IMAGING
(MRI)
 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
Oblique sagittal/oblique coronal scans with t1, t2
Closed mouth, partially open and fully open
positions

55.  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 ")

56. 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

57. 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.

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

59. Osteophyte
lipping of condyle-
osteoarthritis

60. Complete anterior disc displacement
medial section Autopsy Open-mouth MRI

61. anteriorly displaced and deformed, degenerated disc and irregular
cortical outline

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

63. BONE SCINTIGRAPHY
 Sensitive technique
Bone and joint pathology
Intravenous injection of tracer dose of radionuclide-
technetium methylene diphosphonate.
Planar and tomographic images are obtained in all
planes.
Indication-to rule out tumors, condylar
hypoplasia,internal derangement

64. Advantages of bone scintigraphy :
Bone changes are demonstrated before they
are depicted by radiographic examn up to 6 to
12 months earlier in neoplastic involvement.
Up to 2 weeks earlier in bone infection.
Disadvantage
Lack of specificity.
Radionuclide imaging of a patient with
condylar hyperplasia of the left TMJ

65. CONCLUSION
 Complex joint
 Multiple pathologies
 Superimposition and clear view-correct
positioning
 Proper diagnosis and treatment plan

66. References
 White & Pharoah
 Eric whaites
 Karjodkar
 R. Gray.Risk management in clinical practice.
Part 8. Temporomandibular disorders. British
Dental Journal 209, 433 - 449 (2010)