This document discusses various imaging techniques used to image the temporomandibular joint (TMJ). It describes imaging modalities for both osseous and soft tissue structures of the TMJ. For osseous structures, it details panoramic radiography, plain film radiography, computed tomography, and cone beam computed tomography. It provides details on positioning and exposure parameters for transcranial, lateral transcranial, anterior transcranial, and open mouth views used in plain film radiography of the TMJ. Magnetic resonance imaging and ultrasound are mentioned for imaging soft tissues of the TMJ.

1. Temporomandibular Joint
Imaging
Samruddhi Bengal
Roll no- 04
Batch -A

2. Diagnostic Imaging Of TMJ
• The type of imaging technique depends upon the clinical
problems associated, so either imaging of hard tissue
(OSSEOUS) or soft tissue is desired.

3. TMJ Imaging
• Osseous Structure Soft tissue structure
Plain film radiography
Panoramic Radiograph
CT
CBCT
Arthrography
MRI
USG

4. IMAGING OF OSSEOUS STRUCTURES
Panoramic Radiograph
Plain Film Radiograph:
Conventional Tomography
Computed Tomography (CT)

5. Panaromic Radiographs
 The panoramic projection is often included as part of the examination
because it provides an overall view of the teeth and jaws, provides a
means of comparing left and right sides of the mandible, and serves as a
screening projection to identify odontogenic diseases and other disorders
that may be the source of TMJ symptoms.
 Some panoramic machines have specific TMJ programs, but these are of
limited usefulness because of-
thick image layers and the oblique, distorted view of the joint they provide,
which severely limits image quality
 Gross osseous changes in the condyles may be identified, such as
asymmetries, extensive erosions, large osteophytes, tumors or fractures.

7. Plain Film Imaging Modalities
• The plain film usually consists of combinations of
following projections and allows visualization in various
planes:-

8. Structures Shown-
This technique is most useful in detecting arthritic changes
on the articular surface. It helps to evaluate the joint’s bony
relationship.
Film Position-
The cassette is placed flat against the patient’s ear and
centered over the TM joint of interest, against the facial skin
parallel to the sagittal plane.

9. • Position of Patient
The patient’s head is adjusted so that the sagittal plane is
vertical.The ala tragus line is parallel to the floor.
Central Ray
Point of entry of the central ray is ½” behind and 2" above the auditory meatus.
The central ray enters through a point 2" above the external auditory meatus.
The central ray enters through a point ½” anterior and 2" above the external
auditory meatus

10. • Transcranial view is taken with the patient’s mouth in three
positions:
1. Open mouth.
2. Rest position.
3. Closed mouth.
*Exposure Parameters
Intra Oral X-ray Machine
kVp – 70, current 07 mA, time- 1.5 sec

12. • Structures Shown
This view is a lateral projection showing medial surface of
the condylar head and neck, usually taken in the mouth
open position
Film Placement
The cassette is placed flat against the patient’s ear and is
centered to a point ½” anterior to the external auditory
meatus, over the TM joint of interest, against the facial skin
parallel to the sagittal plane.

13. Position of the patient-
• sagital plane parallel to film
• occlusal plane parallel to the long
axis of the film
• pt instructed to slowly inhale during
exposure
• pt should open his mouth
Central Ray
• Is directed from the opposite side
cranially, at an angle of 5 to 10°
posteriorly.

14. *Exposure Parameters
• Using Intra Oral X-ray
Machine
kVp – 65-70, 7-10 mA
current, time- 0.8sec
• Using Extra Oral X-ray
Machine
kVp – 40, 40 mA current,
time- 1 sec.

15. • Structures Shown-
The anterior view of the temporomandibular joint and
medial displacement of fractured condyle and fracture of
neck of condyle are clearly seen in this view.
Film Position-
The film is positioned behind the patient’s head at an angle
of 45°to the sagittal plane.

16. • Position of Patient-
The patient is positioned so that the sagittal plane is vertical.
The canthomeatal line should be 10° to the horizontal, with
the head tipped downwards.
The mouth should be wide open.
Central Ray-
The tube head is placed in front of the patient’s face. The central ray is directed to
the joint of interest, at an angle of +20°, to strike the cassette at right angles.
The point of entry may be taken at:
A. Pupil of the same eye, asking the patient to look straight ahead.
B. Medial canthus of the same eye.
C. Medial canthus of the opposite eye

17. *Exposure Parameters-
Using Intra Oral X-ray
Machine
kVp – 65-70 , current 7-10
mA, time -0.8 sec
Using Extra Oral X-ray
Machine
kVp – 40, current-40 mA,
time- 1 sec

18. • Structures Shown-
This view is primarily meant for viewing the condylar neck
and head. High fractures of the condylar necks,
intracapsular fractures of the TMJ, quality of articular
surfaces, condylar hypoplasia or hypertrophy.
Film Position
The cassette is placed perpendicular to the floor in a
cassette holding device.

19. • Position of Patient
– The sagittal plane should be
vertical and perpendicular to the
film.
– The film is adjusted so that the
lips are centered to the film.
– Only the patient’s forehead
should touch the film
*Exposure Parameters
Using Extra Oral Machine
kVp – 70-80, 60-50 mA current,
time-1.6 sec

20. Thank you