TMJ details and easy to understand it.ppt

easy to understand with pics tmj

1. THE TEMPROMANDIBULARJOINT
(TMJ)
By:
Nour-Eldin A. Nour-Eldin Mohammed

2. Normal Anatomy
Mandibularcondyle(head)
Glenoidfossa
Articulartubercle
(eminence)

3. Lateral pterygoid muscle raphe
Lower head of lateral pterygoid muscle
Anterior band of articular disc
Mandibular condyle (head)
Posterior band of articular disc
Posterior disc attachment

4. Mandibular condyle (head)
Articular disc

5. MRI and autopsy
sections: upper row
oblique sagittalMRI,
asymptomatic
volunteer: left lateral,
middle medial, right
opened mouth

6. Internal Derangements
General orthopedic term implying a mechanical fault
that interferes with the smooth action of a joint
The most common internal derangement is disc
displacement
Clinical Features
Clicking sounds from joint(s)
Restricted or normal mouth opening capacity
Deviation on opening
Pain

7. Imaging Features
Anterior disc displacement: posterior band of the
disc located anterior to the superior portion of
the condyleat closed mouth on oblique sagittal
images
Disc may have normal (biconcave) or deformed
morphology
In opened mouth position disc may be in a
normal position (“with reduction”) or continue to
be displaced (“without reduction”)
Internal Derangements

8. lateral sections central sections open-mouth
Partial anterior disc displacement at baseline

9. Complete anterior disc displacement
Open-mouth MRImedial section Autopsy

10. Lateral disc displacement and normal bone

11. Medial disc displacement
Oblique coronal MRIcoronal MRI

12. Posterior disc displacement

13. Osteoarthritis
Definition
Non-inflammatory focal degenerative disorder of
synovial joints, primarily affecting articularcartilage and
sub-condylarbone; initiated by deterioration of articular
soft-tissue cover and exposure of bone.
Clinical Features
Crepitationsounds from joint(s)
Restricted or normal mouth opening capacity
Pain or no pain from joint areas and/or of mastication
muscles
Occasionally, joints may show inflammatory signs
Women more frequent than men

14. anteriorlydisplaced and deformed, degenerated disc and irregular
cortical outline with osteophytosisand sclerosis of condyle.

15. Advanced osteoarthritis and anterior disc
displacement, with joint effusion

16. Bone Marrow Abnormalities
Definition
Bone marrow edema: serum proteins within
marrow interstitium surrounded by normal
hematopoietic marrow.
Osteonecrosis: complete loss of
hematopoietic marrow.

17. Imaging Features
•Abnormal signal on T2-weighted image from
condylemarrow: increased signal indicates
marrow edema; reduced signal indicates
marrow sclerosis or fibrosis
•Combination of marrow edema signal and
marrow sclerosis signal in condylemost reliable
sign for histologicdiagnosis of osteonecrosis
•Marrow sclerosis signal may indicate advanced
osteoarthritis without osteonecrosis, or
osteonecrosis

18. Arthritides
Definition
Inflammation of synovial membrane characterized by
edema, cellular accumulation, and synovial proliferation
(villous formation).
Clinical Features
Swelling of joint area, not frequently seen in TMJ
Pain (in active disease) from joints
Restricted mouth opening capacity
Morning stiffness, in particular stiff neck
Dental occlusion problems; “my bite doesn’t fit”
Crepitation due to secondary osteoarthritis

19. Rheumatoid arthritis.
After 1 year

20. Rheumatoid arthritis. A MRI shows completely destroyed disc, replaced
by fibrous or vascular pannus and cortical punched-out erosion (arrow)
with sclerosis in condyle.

21. Psoriatic arthropathy. Obliquecoronal and oblique sagittal
CT images show punched-out erosion in lateral part of
condyle (arrow).
Psoriatic arthropathy. MRI shows contrast enhancement
within bone erosion and in joint space, consistent with thickened
synovium/pannus formation. Openmouth
MRI shows reduced condylar translation but normally
located disc (and normal bone in this section)

22. Inflammatory arthritis

23. Ankyloses
Definition
Fibrous or bony union between joint
components.

24. Growth Disturbances (Anomalies)
Definition
Abnormal growth of mandibular condyle; overgrowth,
undergrowth, or bifid appearance.

25. Normal TMJ
Condylar Hypoplasia
Condylar hypoplasia and
facial asymmetry

26. Bifid condyle.

27. Inflammatory or Tumor-like Conditions
Calcium Pyrophosphate Dehydrate Crystal
Deposition Disease (Pseudogout)

28. Benign Tumors
Synovial Chondromatosis
Benign tumor characterized by cartilaginous metaplasia
of synovial membrane, usually in knee, producing small
nodules of cartilage, which essentially separate from
membrane to become loose bodies that may ossify.

29. Synovial Chondromatosis

30. Osteochondroma
Definition
Benign tumor characterized by normal bone and
cartilage, near growth zones.

31. Osteoma

32. Malignant Tumors
Osteosarcoma mandible; 18-yearold female

33. Malignant tumor, mandible; 70-year-old male
with metastasis from lung cancer

34. Thank you