SlideShare a Scribd company logo
1 of 30
TEMPORO-MANDIBULAR
       JOINT
PRESENTED BY:
 BDS/13/10
 BDS/10/10
 BDS/16/10
temporo – WHAT!!
Intro..

 The TMJ is a synovial bilateral joint that permits the mandible
  to move as a unit with 2 functional patterns (gliding and hinge
  movements).
 Translatory movement – in the superior part of the joint as the disc and the
  condyle traverse anteriorly along the inclines of the anterior tubercle to
  provide an anterior and inferior movement of the mandible.
Mouth closed                     Mouth open


 Hinge movement – the inferior portion of the joint between the head of
  the condyle and the lower surface of the disc to permit opening of the
  mandible.
 4 anatomical parts concerned with mandibular articulation:
     Mandibular condyle
     Mandibular fossa and articular eminence
     The articular disc
     The articular capsule
 The mandibular condyle articulates with the glenoid fossa and articular
  eminence of the temporal bone.
 An articular disc separates the articular surfaces so that 2 cavities are
  present:
     Upper compartment between the disc and temporal bone.
     Lower compartment between the condyle and the disc
 The joint capsule is attached below to the articular margin of the head of
  the condyle, and above to the margins of the glenoid fossa and articular
  eminence. The inner aspect of the capsule is lined by a synovial membrane.
 At the sides, the capsule is strengthened by collateral ligaments of which the
  lateral temporomandibular ligament is the strongest.
 The lateral temporo-mandibular ligament is attached above to the zygoma,
  and below, it is attached to the lateral surfaces and posterior border of the
  neck of the mandible.
 There are 2 accessory ligaments associated with the TMJ:
     The stylomandibular ligament attaches to the styloid process and to the
      posterior border of the ramus.
     The sphenomandibular ligament extends between the spine of the
      sphenoid bone and the lingula of the mandible.
 These ligaments limit the range of movement of the condyle preventing it
  from coming in contact with the tympanic plate behind and passing beyond
  the articular eminence in front.
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 posteriorly.
     The long axis of the two poles deviate
       posteriorly and meets at the anterior
       border of the foramen magnum.
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.
 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.
The fibrous articular covering of
                the condyle under the EM.



1.   Fibrous layer
2.   Cartilage
3.   Bone
4.   Bone marrow
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.
 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.
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.
 Attachment: Medial and lateral
   poles of the condyle by medial
   and lateral ligaments.




 Divide the joint into: Upper
   (larger) compartment and
   lower (smaller) compartment.
 Anterior border divides into upper and lower lamellae that run forward.
 The upper lamella fuses with the anterior slope of the articular eminence.
 The lower lamella attaches to the front of the neck of the condyle.
 Fibers of the superior head of the lateral pterygoid muscle is attached to the
  anterior border.
 Posterior border divides into upper and lower lamellae
     The upper lamella is fibrous and elastic and fuses with the capsule and is
      inserted in the squamotympanic fissure.
     The lower lamella, non elastic, attaches to the back of the condyle.
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.
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 TMJ ligaments.
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.
Synovial fluid
 It is clear, straw-colored viscous fluid.
 It diffuses out from the rich cappillary network of the synovial membrane.
Contains:
 Hyaluronic acid which is highly viscous
 May also contain some free cells mostly macrophages.
Functions:
 Lubricant for articulating surfaces.
 Carry nutrients to the avascular tissue of the joint.
 Clear the tissue debris caused by normal wear and tear of the articulating
  surfaces.
Blood supply
 4 arteries supply the joint:
     Superficial temporal
     Deep auricular
     Anterior tympanic
     Ascending pharyngeal
 Branches from the 4 approach the joint and penetrate the capsule.
Nerve supply
 Branches from the mandibular nerve
     Auriculotemporal nerve
     Masseteric nerve
     Deep temporal nerves
 Supply all surfaces of the head, fossa, capsule and part of the disk.
AGE CHANGES
   Condyle:
      Becomes more flattened
      Fibrous capsule becomes thicker.
      Osteoporosis of underlying bone.
      Thinning or absence of cartilaginous zone.
   Disk:
      Becomes thinner.
      Shows hyalinization and chondroid changes.
   Synovial fold:
      Become fibrotic with thick basement membrane.
   Blood vessels and nerves:
      Walls of blood vessels thickened.
      Nerves decrease in number
Changes could lead to:
 Dysfunction in old age
 Impairment of motion due to decrease in the extensibility of the disk and
  the capsule.
 Decrease in the secretion of the synovial fluid.
THE END!! YOU CAN NOW WAKE   UP…

More Related Content

What's hot

Muscles of facial expression
Muscles of facial expressionMuscles of facial expression
Muscles of facial expression
Dr. SHEETAL KAPSE
 
Growth & development of maxilla and mandible
Growth & development of maxilla and mandibleGrowth & development of maxilla and mandible
Growth & development of maxilla and mandible
Piyush Verma
 

What's hot (20)

TEMPOROMANDIBULAR JOINT
TEMPOROMANDIBULAR JOINT TEMPOROMANDIBULAR JOINT
TEMPOROMANDIBULAR JOINT
 
Anatomy of temporomandibular joint
Anatomy of temporomandibular jointAnatomy of temporomandibular joint
Anatomy of temporomandibular joint
 
Muscles of facial expression
Muscles of facial expressionMuscles of facial expression
Muscles of facial expression
 
Tmj anatomy
Tmj anatomyTmj anatomy
Tmj anatomy
 
Tmj
TmjTmj
Tmj
 
Mandibular nerve
Mandibular nerveMandibular nerve
Mandibular nerve
 
Muscles of mastication
Muscles of masticationMuscles of mastication
Muscles of mastication
 
Temporomandibur joint
Temporomandibur jointTemporomandibur joint
Temporomandibur joint
 
Mandibular nerve
Mandibular nerve Mandibular nerve
Mandibular nerve
 
Growth & development of maxilla and mandible
Growth & development of maxilla and mandibleGrowth & development of maxilla and mandible
Growth & development of maxilla and mandible
 
Temporomandibular joint
Temporomandibular jointTemporomandibular joint
Temporomandibular joint
 
Temporomandibular Joint
Temporomandibular JointTemporomandibular Joint
Temporomandibular Joint
 
Oral physiology - The temporomandibular joint
Oral physiology - The temporomandibular jointOral physiology - The temporomandibular joint
Oral physiology - The temporomandibular joint
 
Temporomandibular joint 1
Temporomandibular joint 1Temporomandibular joint 1
Temporomandibular joint 1
 
Theories of tooth eruption
Theories of tooth eruptionTheories of tooth eruption
Theories of tooth eruption
 
Muscles attached to the mandible
Muscles attached to the mandibleMuscles attached to the mandible
Muscles attached to the mandible
 
Muscles of mastication
Muscles of masticationMuscles of mastication
Muscles of mastication
 
tmj
tmjtmj
tmj
 
Mandible
MandibleMandible
Mandible
 
Anatomy of face
Anatomy of faceAnatomy of face
Anatomy of face
 

Viewers also liked (6)

Tmj disorders
Tmj disordersTmj disorders
Tmj disorders
 
Tmj disorder
Tmj disorderTmj disorder
Tmj disorder
 
Temporomandibular Joint Disorder
Temporomandibular Joint DisorderTemporomandibular Joint Disorder
Temporomandibular Joint Disorder
 
Temporomandibular joint disorders II
Temporomandibular joint disorders IITemporomandibular joint disorders II
Temporomandibular joint disorders II
 
Temporomandibular joint disorder
Temporomandibular joint  disorderTemporomandibular joint  disorder
Temporomandibular joint disorder
 
Tmj disorder
Tmj disorderTmj disorder
Tmj disorder
 

Similar to Temporo mandibular joint

anatomyoftemporomandibularjoint-210112114624.pdf
anatomyoftemporomandibularjoint-210112114624.pdfanatomyoftemporomandibularjoint-210112114624.pdf
anatomyoftemporomandibularjoint-210112114624.pdf
snithiyuvarajayuvara
 
TMJ surgical anatomy and applied aspects
TMJ surgical anatomy and applied aspectsTMJ surgical anatomy and applied aspects
TMJ surgical anatomy and applied aspects
Joel D'silva
 
Temporomandibular joints 20 sept '13
Temporomandibular joints 20 sept '13Temporomandibular joints 20 sept '13
Temporomandibular joints 20 sept '13
hishashwati
 

Similar to Temporo mandibular joint (20)

histology of tempromandibular joint
histology of tempromandibular jointhistology of tempromandibular joint
histology of tempromandibular joint
 
Temporomandibular joint by dr.vibhuti amin
Temporomandibular joint by dr.vibhuti aminTemporomandibular joint by dr.vibhuti amin
Temporomandibular joint by dr.vibhuti amin
 
ANATOMY TEMPOROMANDIBULAR JUNCTION OF HUMAN
ANATOMY TEMPOROMANDIBULAR JUNCTION OF HUMANANATOMY TEMPOROMANDIBULAR JUNCTION OF HUMAN
ANATOMY TEMPOROMANDIBULAR JUNCTION OF HUMAN
 
anatomyoftemporomandibularjoint-210112114624.pdf
anatomyoftemporomandibularjoint-210112114624.pdfanatomyoftemporomandibularjoint-210112114624.pdf
anatomyoftemporomandibularjoint-210112114624.pdf
 
TEMPROMANDIBULAR JOINT
TEMPROMANDIBULAR JOINTTEMPROMANDIBULAR JOINT
TEMPROMANDIBULAR JOINT
 
Surgical anatomy of temporomandibular joint
Surgical anatomy of temporomandibular jointSurgical anatomy of temporomandibular joint
Surgical anatomy of temporomandibular joint
 
temporomandibular joint.pptx
temporomandibular joint.pptxtemporomandibular joint.pptx
temporomandibular joint.pptx
 
Temporomandibular joint Disorder in oral pathology
Temporomandibular joint Disorder in oral pathology Temporomandibular joint Disorder in oral pathology
Temporomandibular joint Disorder in oral pathology
 
Tmj surgical anatomy and approaches
Tmj surgical anatomy and approachesTmj surgical anatomy and approaches
Tmj surgical anatomy and approaches
 
TMJ surgical anatomy and applied aspects
TMJ surgical anatomy and applied aspectsTMJ surgical anatomy and applied aspects
TMJ surgical anatomy and applied aspects
 
1 anatomy & physiology of tmj
1 anatomy & physiology of tmj1 anatomy & physiology of tmj
1 anatomy & physiology of tmj
 
TMJ
TMJTMJ
TMJ
 
Anatomy and physiology of TMJ /orthodontic courses by Indian dental academy
Anatomy and physiology of TMJ   /orthodontic courses by Indian dental academy Anatomy and physiology of TMJ   /orthodontic courses by Indian dental academy
Anatomy and physiology of TMJ /orthodontic courses by Indian dental academy
 
DR SHAKIR New anatomy of tmj
DR SHAKIR New anatomy of tmjDR SHAKIR New anatomy of tmj
DR SHAKIR New anatomy of tmj
 
Tmj
TmjTmj
Tmj
 
Temporomandibular joints 20 sept '13
Temporomandibular joints 20 sept '13Temporomandibular joints 20 sept '13
Temporomandibular joints 20 sept '13
 
Tmj
TmjTmj
Tmj
 
TMJ
TMJTMJ
TMJ
 
Tmj
TmjTmj
Tmj
 
Temporomandibular joint
Temporomandibular jointTemporomandibular joint
Temporomandibular joint
 

Recently uploaded

Cardiac Impulse: Rhythmical Excitation and Conduction in the Heart
Cardiac Impulse: Rhythmical Excitation and Conduction in the HeartCardiac Impulse: Rhythmical Excitation and Conduction in the Heart
Cardiac Impulse: Rhythmical Excitation and Conduction in the Heart
MedicoseAcademics
 
THORACOTOMY . SURGICAL PERSPECTIVES VOL 1
THORACOTOMY . SURGICAL PERSPECTIVES VOL 1THORACOTOMY . SURGICAL PERSPECTIVES VOL 1
THORACOTOMY . SURGICAL PERSPECTIVES VOL 1
DR SETH JOTHAM
 

Recently uploaded (20)

TUBERCULINUM-2.BHMS.MATERIA MEDICA.HOMOEOPATHY
TUBERCULINUM-2.BHMS.MATERIA MEDICA.HOMOEOPATHYTUBERCULINUM-2.BHMS.MATERIA MEDICA.HOMOEOPATHY
TUBERCULINUM-2.BHMS.MATERIA MEDICA.HOMOEOPATHY
 
Pharmacology of drugs acting on Renal System.pdf
Pharmacology of drugs acting on Renal System.pdfPharmacology of drugs acting on Renal System.pdf
Pharmacology of drugs acting on Renal System.pdf
 
Hemodialysis: Chapter 2, Extracorporeal Blood Circuit - Dr.Gawad
Hemodialysis: Chapter 2, Extracorporeal Blood Circuit - Dr.GawadHemodialysis: Chapter 2, Extracorporeal Blood Circuit - Dr.Gawad
Hemodialysis: Chapter 2, Extracorporeal Blood Circuit - Dr.Gawad
 
Cervical screening – taking care of your health flipchart (Vietnamese)
Cervical screening – taking care of your health flipchart (Vietnamese)Cervical screening – taking care of your health flipchart (Vietnamese)
Cervical screening – taking care of your health flipchart (Vietnamese)
 
TEST BANK for The Nursing Assistant Acute, Subacute, and Long-Term Care, 6th ...
TEST BANK for The Nursing Assistant Acute, Subacute, and Long-Term Care, 6th ...TEST BANK for The Nursing Assistant Acute, Subacute, and Long-Term Care, 6th ...
TEST BANK for The Nursing Assistant Acute, Subacute, and Long-Term Care, 6th ...
 
Cardiac Impulse: Rhythmical Excitation and Conduction in the Heart
Cardiac Impulse: Rhythmical Excitation and Conduction in the HeartCardiac Impulse: Rhythmical Excitation and Conduction in the Heart
Cardiac Impulse: Rhythmical Excitation and Conduction in the Heart
 
TEST BANK For Lewis's Medical Surgical Nursing in Canada, 4th Edition by Jane...
TEST BANK For Lewis's Medical Surgical Nursing in Canada, 4th Edition by Jane...TEST BANK For Lewis's Medical Surgical Nursing in Canada, 4th Edition by Jane...
TEST BANK For Lewis's Medical Surgical Nursing in Canada, 4th Edition by Jane...
 
Video capsule endoscopy (VCE ) in children
Video capsule endoscopy (VCE ) in childrenVideo capsule endoscopy (VCE ) in children
Video capsule endoscopy (VCE ) in children
 
Effects of vaping e-cigarettes on arterial health
Effects of vaping e-cigarettes on arterial healthEffects of vaping e-cigarettes on arterial health
Effects of vaping e-cigarettes on arterial health
 
In-service education (Nursing Mangement)
In-service education (Nursing Mangement)In-service education (Nursing Mangement)
In-service education (Nursing Mangement)
 
Tips and tricks to pass the cardiovascular station for PACES exam
Tips and tricks to pass the cardiovascular station for PACES examTips and tricks to pass the cardiovascular station for PACES exam
Tips and tricks to pass the cardiovascular station for PACES exam
 
Retinal consideration in cataract surgery
Retinal consideration in cataract surgeryRetinal consideration in cataract surgery
Retinal consideration in cataract surgery
 
THORACOTOMY . SURGICAL PERSPECTIVES VOL 1
THORACOTOMY . SURGICAL PERSPECTIVES VOL 1THORACOTOMY . SURGICAL PERSPECTIVES VOL 1
THORACOTOMY . SURGICAL PERSPECTIVES VOL 1
 
Factors Affecting child behavior in Pediatric Dentistry
Factors Affecting child behavior in Pediatric DentistryFactors Affecting child behavior in Pediatric Dentistry
Factors Affecting child behavior in Pediatric Dentistry
 
CT scan of penetrating abdominopelvic trauma
CT scan of penetrating abdominopelvic traumaCT scan of penetrating abdominopelvic trauma
CT scan of penetrating abdominopelvic trauma
 
Vaccines: A Powerful and Cost-Effective Tool Protecting Americans Against Dis...
Vaccines: A Powerful and Cost-Effective Tool Protecting Americans Against Dis...Vaccines: A Powerful and Cost-Effective Tool Protecting Americans Against Dis...
Vaccines: A Powerful and Cost-Effective Tool Protecting Americans Against Dis...
 
TEST BANK For Huether and McCance's Understanding Pathophysiology, Canadian 2...
TEST BANK For Huether and McCance's Understanding Pathophysiology, Canadian 2...TEST BANK For Huether and McCance's Understanding Pathophysiology, Canadian 2...
TEST BANK For Huether and McCance's Understanding Pathophysiology, Canadian 2...
 
Cardiovascular Physiology - Regulation of Cardiac Pumping
Cardiovascular Physiology - Regulation of Cardiac PumpingCardiovascular Physiology - Regulation of Cardiac Pumping
Cardiovascular Physiology - Regulation of Cardiac Pumping
 
DIGITAL RADIOGRAPHY-SABBU KHATOON .pptx
DIGITAL RADIOGRAPHY-SABBU KHATOON  .pptxDIGITAL RADIOGRAPHY-SABBU KHATOON  .pptx
DIGITAL RADIOGRAPHY-SABBU KHATOON .pptx
 
Compare home pulse pressure components collected directly from home
Compare home pulse pressure components collected directly from homeCompare home pulse pressure components collected directly from home
Compare home pulse pressure components collected directly from home
 

Temporo mandibular joint

  • 2. PRESENTED BY: BDS/13/10 BDS/10/10 BDS/16/10
  • 4. Intro..  The TMJ is a synovial bilateral joint that permits the mandible to move as a unit with 2 functional patterns (gliding and hinge movements).
  • 5.  Translatory movement – in the superior part of the joint as the disc and the condyle traverse anteriorly along the inclines of the anterior tubercle to provide an anterior and inferior movement of the mandible.
  • 6. Mouth closed Mouth open  Hinge movement – the inferior portion of the joint between the head of the condyle and the lower surface of the disc to permit opening of the mandible.
  • 7.  4 anatomical parts concerned with mandibular articulation:  Mandibular condyle  Mandibular fossa and articular eminence  The articular disc  The articular capsule
  • 8.  The mandibular condyle articulates with the glenoid fossa and articular eminence of the temporal bone.  An articular disc separates the articular surfaces so that 2 cavities are present:  Upper compartment between the disc and temporal bone.  Lower compartment between the condyle and the disc
  • 9.  The joint capsule is attached below to the articular margin of the head of the condyle, and above to the margins of the glenoid fossa and articular eminence. The inner aspect of the capsule is lined by a synovial membrane.
  • 10.  At the sides, the capsule is strengthened by collateral ligaments of which the lateral temporomandibular ligament is the strongest.  The lateral temporo-mandibular ligament is attached above to the zygoma, and below, it is attached to the lateral surfaces and posterior border of the neck of the mandible.
  • 11.  There are 2 accessory ligaments associated with the TMJ:  The stylomandibular ligament attaches to the styloid process and to the posterior border of the ramus.  The sphenomandibular ligament extends between the spine of the sphenoid bone and the lingula of the mandible.  These ligaments limit the range of movement of the condyle preventing it from coming in contact with the tympanic plate behind and passing beyond the articular eminence in front.
  • 12. 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 posteriorly.  The long axis of the two poles deviate posteriorly and meets at the anterior border of the foramen magnum.
  • 13. 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.
  • 14.  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.
  • 15. The fibrous articular covering of the condyle under the EM. 1. Fibrous layer 2. Cartilage 3. Bone 4. Bone marrow
  • 16. 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.
  • 17.  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.
  • 18. 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.
  • 19.  Attachment: Medial and lateral poles of the condyle by medial and lateral ligaments.  Divide the joint into: Upper (larger) compartment and lower (smaller) compartment.
  • 20.  Anterior border divides into upper and lower lamellae that run forward.  The upper lamella fuses with the anterior slope of the articular eminence.  The lower lamella attaches to the front of the neck of the condyle.  Fibers of the superior head of the lateral pterygoid muscle is attached to the anterior border.
  • 21.  Posterior border divides into upper and lower lamellae  The upper lamella is fibrous and elastic and fuses with the capsule and is inserted in the squamotympanic fissure.  The lower lamella, non elastic, attaches to the back of the condyle.
  • 22. 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.
  • 23. 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 TMJ ligaments.
  • 24. 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.
  • 25. Synovial fluid  It is clear, straw-colored viscous fluid.  It diffuses out from the rich cappillary network of the synovial membrane. Contains:  Hyaluronic acid which is highly viscous  May also contain some free cells mostly macrophages. Functions:  Lubricant for articulating surfaces.  Carry nutrients to the avascular tissue of the joint.  Clear the tissue debris caused by normal wear and tear of the articulating surfaces.
  • 26. Blood supply  4 arteries supply the joint:  Superficial temporal  Deep auricular  Anterior tympanic  Ascending pharyngeal  Branches from the 4 approach the joint and penetrate the capsule.
  • 27. Nerve supply  Branches from the mandibular nerve  Auriculotemporal nerve  Masseteric nerve  Deep temporal nerves  Supply all surfaces of the head, fossa, capsule and part of the disk.
  • 28. AGE CHANGES  Condyle:  Becomes more flattened  Fibrous capsule becomes thicker.  Osteoporosis of underlying bone.  Thinning or absence of cartilaginous zone.  Disk:  Becomes thinner.  Shows hyalinization and chondroid changes.  Synovial fold:  Become fibrotic with thick basement membrane.  Blood vessels and nerves:  Walls of blood vessels thickened.  Nerves decrease in number
  • 29. Changes could lead to:  Dysfunction in old age  Impairment of motion due to decrease in the extensibility of the disk and the capsule.  Decrease in the secretion of the synovial fluid.
  • 30. THE END!! YOU CAN NOW WAKE UP…