In this slide we talk about temporomandibular joint disorders Its introduction,classification , anatomy , histology in details Also cover articular disorder Traumatic disturbances Non articular disorders Development disturbance etc.

1. College of Dental
Science and Hospital,
Rau
Topic :- TMJ
Guided by:- Dr. Mahesh Melkundi
M.D.S (Professor & HOD)
Dr. Sandeep Sharma M.D.S (Reader)
Dr. Reshna Roy M.D.S (Senior lecturer)
Submitted by:- Himanshu dhakad BDS 3rd Year)

2. TMJ
INTRODUCTION
TMJ is the articulation between the head of the
mandible and the mandibular fossa and articular
tubercle of the temporal bone.

3. ➤ It is considered as a synovial joint of the
condylar variety.
➤ It is classified as a compound joint because
it is made up of 3 bones:
➤ Anterior part of mandibular fossa and
articular tubercle of temporal bone.
➤ Head of the mandible.
➤ Articular disc ( serves as a nonossified
bone).

5. DEVELOPMENT OF TMJ
❖ At approximately 10 weeks the components of future joint
become evident in the mesenchyme between the condylar
cartilage of mandible and temporal bone
❖ Two slitlike joint cavities and an intervening disk make their
appearance in this region by 12 weeks.
The mesenchyme around the joint begins to form the fibrous joint
capsule.

6. Anatomy of
Temporomandibular
Joint

7. TEMPOROMANDIBULAR JOINT (TMJ) ANATOMY
➤The TMJ is a synovial bilateral joint that permits
the mandible to move as a unit with 2 functional
patterns (gliding and hinge movements)
➤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..

8. ➤ 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.

9. 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 end point
of closure that of the teeth making occlusal contact.

10. COMPONENTS
➤ (Bone/Hard components)
➤ Mandibular condyle
➤ Glenoid fossa of the temporal bone
➤ Articular eminence
➤ Soft tissue components)
➤ Capsule
➤ Articular disc
➤ Ligaments
➤ Muscular component

11. THE MANDIBULAR CONDYLE
➤It's the articulating surface of the
mandible.
➤It is convex in all directions but
wider latero-medially than antero-
posteriorly.
It has lateral and medial poles:
➤The medial pole is directed more
posteriorl
➤The long axis of the two poles
deviate posteriorly and meets at the
anterior border of the foramen
magnum.

12. HISTOLOGY
➤Composed of cancellous bone covered by a thin layer
of compact bone.
➤Trabeculae: of the cancellous bone is arranged in a
radiating manner from the neck to reach the surface of
the condyle at a right angle (to give maximum strength.
➤Bone marrow is of myeloid or cellular type and
becomes fatty with age.

13. ➤Outer layer of compact bone is covered by thick layers of fibrous
tissues composed of:
➤Superficial layer: network of strong collagen fibers,
chondrocytes and fibroblasts.
➤Deep layer: thin collagen fibers rich in chondroid cells during
growth period (hyaline cartilage).
➤Growth occur by apposition from the deepest layer - the
deepest surface of the cartilaginous plate is replaced by bone.
➤Growth continues till 21 years of age.
➤Remnants of cartilage may persist in old age.

14. MANDIBULAR (GLENOID) FOSSA
AND ARTICULAR EMINENCE
➤Glenoid fossa:
Posteriorly limited by the
squamotympanic fissure.
Anterioly bounded by the articular
eminence.
Roof: thin layer of compact bone
separating the middle cranial fossa.
➤Articular eminence:
Composed of: Spongy bone covered by
thin layer of compact bone.
Chondroid tissues commonly seen in
the eminence.

15. ➤Fibrous layer covering the articulating surface of
temporal bone.
➤Thin on the articular fossa and thickens on the
posterior slope of the eminence
➤Over the eminence the fibrous tissues are arranged in
3 zones:
Inner zone - fibers arranged at right angle to surface
Outer zone - fibers run parallel to the bone surface
Intermediate zone - transitional zone. Fibers are
interlaced.

16. INTERARTICULAR DISC
(MENISCUS)
➤ Disk is fibrous, avascular, non inverted plate
➤Shape is oval, biconcave in sagittal section. It is thin
in central part and thick at posterior borders.

17. ➤ Attachment: Medial and
lateral poles of the condyle by
medial and lateral ligaments.
➤Divide the joint into:
Upper (larger) compartment
and lower (smaller)
compartment.

18. HISTOLOGY
• Composed of dense fibrous tissue containing:
• Straight and tightly packed collagenous fibers
• Few elastic fibers.
• Some chondroid cells appear with age.
• Chondrocytes may be seen.
• The space between upper and lower posterior is
filled with highly
• vascular loose connective tissue.

19. ARTICULATING CAPSULE AND LIGAMENTS
AND SYNOVIAL MEMBRANE
➤The whole TMJ is enclosed in a
fibrous capsule.
➤It is attached to:
• Articular tubercle (in front)
• Lips of squamous tympanic
fissure (posteriorly)
• Borders of articulating glenoid
fossa
• Neck of the mandible. (below)
• ➤It is lined by synovial
membrane.
• ➤Laterally, the capsule is
reinforced by TM ligaments.

20. HISTOLOGY
➤Consists of 2 layers:
• * Outer fibrous capsule - strengthen laterally to form the
temporomandibular ligament. ➤Inner
synovial layer - composed of thin connective tissue layer
lined with:
• + Synovial cells
• Type A: secretes hyaluronic acid
• Type B: produces protein rich secretion.
• + Synovial folds and villi protrude from the surface into the
joint cavity.
• Synovial layer of cells line the entire capsule of both upper
and lower joint spaces.
• + Synovial membrane is very rich in blood supply and
contains lymphatic vessels.

21. Muscle
• Masseter
• Temporalis
• Medial pterygoid
• Lateral pterygoid

22. ➤Elevation of Mandible
Temporalis
Masseter
Medial Pterygoids
➤Depression Of Mandible
Lateral pterygoid
Digastric
Geniohyoid
➤Protrusion of Mandible
Lateral Pterygoids
Medial Pterygoids
➤Retraction of Mandible
Posterior fibres of Temporalis

23. Temporomandibular Joint
Disorders

24. ARTICULAR DISORDERS
👉DEVELOPMENTAL DISTURBANCES
Aplasia of the manibular condyle
Hypoplasia of mandibular condyle
Hyperplasia of manidbular condyle

25. TRAUMATIC DISTURBANCES
• Internal disc derangements Anterior disc
displacement
• Posterior disc displacement
• Dislocations
• Luxation (Complete dislocation)
• Subluxation (Incomplete dislocation)
• Ankylosis (hypomobility)
• Injuries of Articular disck (Meniscus)
• Fracture of condyle

26. ➤INFLAMMATORY DISTURBANCES
Arthiritis
Infectious arthritis (bacterial, viral and fungal)
Rheumatoid arthiritis
Osteoarthiritis or degenerative joint disease
➤NEOPLASTIC DISTURBANCES
Benign: osteoma, chondroma
Malignant : primary, metastatic

27. NON ARTICULAR DISORDERS
➤MUSCULAR DISORDERS
• 1. Muscle spasm
• 2. Myofacial pain dysfunction syndrome
• 3. Myotonic dystrophies
• 4. Myositis ossificans progressiva
• 5. Fibromyalgia
• ➤SYNDROME ASSOCIATED
• Costen's syndrome
• Temperomandibular joint syndrome

28. DEVELOPMENTAL DISTURBANCES
OF TMJ
• ➤APLASIA OF THE MANDIBULAR CONDYLE
• Is the failure of development of the mandibular
condyle
• Synonym
• Condylar Aplasia