it has contents about the anatomy, physiology and the histology of TMJ

1. ANATOMY ,PHYSIOLOGY AND HISTOLOGY
DR .PURNIMA .VADLA

2.  TYPES OF JOINTS
 EVOLUTION
 EMBRYOLOGY
 ANATOMY
 PHYSIOLOGY
 HISTOLOGY

3. TYPES OF JOINTS
FIBROUS CARTILAGENOUS SYNOVIAL

4. GHOMPHOSIS
SUTURE
SYNCHONDROSES
SYMPHYSES
SYNDESMOSES
DIARTHROSIS

5.  SYNOVIAL CAVITY
 JOINT CAPSULE
 ARTICULAR CARTILAGE
 ARTICULAR DISCS OR MENISCI
 ARTICULAR FAT PADS
 TENDONS
 ACCESSORY LIGAMENTS
 BURSAE

6. DIARTHROIDAL
GINGLYMOID
TRUE
COMPOUND
SYNOVIAL

7. TMJ
Two blastemas.
[condylar
&temporal]
Fibrous cartilage is
present on the
articular surfaces
which acts as a
growth centre.
OTHER
SYNOVIAL
JOINTS
Single blastema
helps in the entire
cavity formation.
Hyaline cartilage is
present on the
articular surfaces
which does not act as
the growth centre.

8. QUADRATE
DENTARY
ARTICULAR
Fig ; shows a
QUADRATE –
ARTICULAR JOINT
in early vertebrates.

9. REPTILES
DENTARY –SQUAMOSAL JOINT
QUADRATE- ARTICULAR JOINT
DENTARY BONE INCREASING
IN SIZE

10. PRENATAL TMJ DEVELOPMENT
First brachial arch

11. MECKEL’S CARTILAGE [Skeletal
support for lower jaw]
TERMINATES DORSALLY INTO
MALLEUS
[ARTICULARE]
INCUS
[QUADRATE]
Together forms primitive joint which exists till the 4th month
of IUL.

12. 10
WEEKS
CONDYLAR BLASTEMATEMPORAL BLASTEMA
GLENOID FOSSA HEAD OF CONDYLE
INTERPOSED WITH CONNECTIVE TISSUE
INFERIOR
COMPARTMENT
[10 weeks]
SUPERIOR
COMPARTMENT
[ 11 ½ weeks ]

13. TEMPORAL BLASTEMA
CONDYLAR BLASTEMA

14. Articular disk [10th week]
Fibrous capsule [11th week]

15.  STABILIZED CAPSULE
 FLAT GLENOID FOSSA
 ARTICULAR EMINENCE ABSENT

16. Condyle
 Mediolateral width
 9.6mm at birth
 12.4mm at deciduous point
 15mm in permanent dentition
 Anteroposterior
 Faster than mediolateral growth
 6.5mm - from eruption to completion of deciduous
teeth.
 7.3mm - adult size

17. New borns – head projects
posteriorly, has flat
surface
Highest peak point is in
the center – at mixed
dentition
The cartilage slowly
changes to fibrocartilage
as the age progresses

18. Glenoid Fossa
• 1.2-1.3cm – eruption of deciduous dentition
• Anterior inclination increases drastically as teeth
erupt & becomes 3 times steeper in permanent dentition
Articular Eminence
• Outline and inclination dos not change markedly from
deciduous to permanent dentition
• Growth increases after complete eruption of lateral and
central incisors
Articular Disc
• The intermediate zone – vascularity reduces as the age
progresses

19.  Stop growing at 20 years of age - continuous
adaptational responses.
Condylar head –
 Decrease in convexity
 Decrease in condylar height
 Resorption more on lateral aspect than medial
 In extreme cases, drastic changes may produce
disappearance of condyle

20. Glenoid fossa and articular eminence –
Flattening of the articular fossa.
Decrease in articular eminence.
Decrease in the vertical dimension of the glenoid fossa
Flattening of the sigmoid curve.

21. ARTICULAR
COMPONENTS
BONY
1.CRANIAL COMPONENT
2.MANDIBULAR
COMPONENT
SOFT TISSUE
1.ARTICULAR DISC
2.FIBROUS CAPSULE
3.RETRODISCAL TISSUES
PARA
ARTICULAR
COMPONENTS
LIGAMENTS
1. TRUE
2.ACCESORY
MUSCLES
A
N
A
T
O
M
Y

22. BONY COMPONENTS
GLENOID FOSSA ARTICULAR EMINENSE
CONDYLES

23. SOFT TISSUE COMPONENTS
ARTICULAR DISC
JOINT
CAPSULE
LATERAL
LIGAMENT
JOINT CAPSULE

24. ARTICULAR DISC
REES[ 1954]- FOUR ZONES
POSTERIOR BAND
SRL
INTERMEDIATE BAND
ANTERIOR BAND
IRL

25. SYNOVIAL MEMBRANE

26. • PROTEINS-MUCIN,GAGS
• MUCOPOLYSACCHARIDES
• CELLS- EPITHELIAL CELLS.
MACROPHAGESCONTENTS
• LUBRICATION
• NUTRIOTION
• SHOCK ABSORBER
FUNCTION

27. • MOVING JOINT
• SYNOVIAL FLUID FORCED FROM ONE
AREA OF THE JOINT TO ANOTHER.
• PRIMARY MECHANISM
BOUNDARY
LUBRICATION
• COMPRESSED BT NOT A MOVING JOINT
• SYNOVIAL FLUID FORCED IN AND OUT
OF ARTICULAR SURFACES BECOZ OF
COMPRESSION.
• MECHANISM OF METABOLIC
EXCHANGE
WEEPING
LUBRICATION

28. LIGAMENTS –NON ELASTIC COLLAGENOUS STRUCTURES
• Sphenomandibular
• Stylomandibular
True ligamentsAccessory
• Collateral / Discal
• Capsular
• Lateral /
Temporomandibular

29. COLLATERAL LIGAMENT
CAPSULAR LIGAMENT

31. • Orientation
• Origin
• Insertion
• Function
Outer part
• oblique
• Lateral aspect of
articular tubercle
• Posterior surface
of condylar neck
• Limits inferior
distraction &
rotational
movement
Inner part
• horizontal
• Medial to outer
part
• Lateral pole of
condyle
• Limits posterior
distraction

32. SPHENOMANDIBULAR LIGAMENT
STYLOMANDIBULAR LIGAMENT

33. Attach to
ramus & neck
of condyle
Predominantly
elevators
Body &
symphysis with
hyoid bone
Predominantly
depressors
Supra
mandibular
Infra
mandibular
MUSCLES

34. MASSETER

35. Superficial head Deep head
Origin Lower border of
Zygomatic bone & ant.
2/3rd of Zygomatic arch
Inner surface entire
zygomatic arch & post
1/3rd of arch from its
lower border
Insertion Angle Lateral aspect of ramus
above insertion of
superficial head
EMG studies
Silent during
Active during
Forced retrusion
Protrusion
Protrusion
Forced retrusion
Functions
Active Contralateral
movements
Ipsilateral movements

36. TEMPORALIS
CLOSING MOVEMENTS !

37. LATERAL PTERYGOID

38. MEDIAL PTERYGOID

39. SUPRAHYOID MUSCLES INFRAHYOID MUSCLES

40. INNERVATION OF TMJ
- The trigeminal nerve , that provides both motor & sensory innervations to
muscles that control it.
- Afferent innervation – branches of mandibular nerve.
- Also by auriculo-temporal nerve as it leaves mandibular nerve behind joint &
ascends laterally & superior to wrap around posterior region of joint.
- Additional nerves – temporal & masseteric .

41. VASCULARIZATION
- predominantly
i) from posterior- superficial temporal artery
ii) from anterior- middle meningeal artery
iii) from inferior- internal maxillary artery
iv) others :
- the deep auricular
- anterior tympanic
- ascending pharyngeal arteries
- condyle, receives through its marrow spaces by “feeder vessels” from inferior alveolar
artery.

43. MOVEMENTS
HORIZONTAL
AXIS OF
ROTATION
FRONTAL OR
VERTICAL AXIS
OF ROTATION
SAGITTAL AXIS
OF ROTATION
TRANSLATION

44. AROUND THE HORIZONTAL/HINGE AXIS

45. AROUND THE FRONTAL OR
VERTICAL AXIS

46. AROUND THE SAGITTAL
AXIS

47. TRANSLATION

48.  12 O’ POSITION
 TONUS OF ELVATORS CONSTANT CONTACT
 LOW PRESSURE WEN DISC SPACE IS WIDE
 NO ELASTIC TRACTION ON DISC
 OCLLUSION- PHYSIOLOGICAL REST POSITION-
HINGE
 BEYOND PHYSIOLOGIC REST POSITION AND
EXCURSIVE MOVEMENTS-HINGE + TRANSLATORY

49. Condyle rotates on disc and inferior head of lateral pterygoid
Disc glides on the fossa down the articular eminense.
Superior retrosternal ligament stretched.
Increases forces to retract disc.
Active muscles-inf .lateral pterygoid ,suprahyoid,infrahyoid
Balancing muscles- temporalis, masseter, medial pterygoid

51. Strech in SRL retracts disc-disc guides posteriorly.
Elevator muscles bilateral
Relaxed lateral pterygoid
Condyle comes back to closed joint position.

54. LEFT
LEFT LATERAL
BORDER
MOVEMENTS
CONTINUED LEFT
LATERAL BORDER
MOVEMENTS WITH
PROTRUSION
RIGHT
RIGHT LATERAL
BORDER
MOVEMENTS
CONTINUED RIGHT
LATERAL BORDER
MOVEMENTS WITH
PROTRUSION
LATERAL MOVEMENTS

55. LEFT LATERAL BORDER
MOVEMENT
CONTINUED LEFT LATERAL
BORDER MOVEMENT WITH
PROTRUSION
LEFT CONDYLE; WORKING OR ROTATORY
RIGHT CONDYLE; NON WORKING OR ORBITING

56. RIGHT LATERAL BORDER
MOVEMENTS
CONTINUED RIGHT LATERAL
BORDER MOVEMENT WITH
PROTRUSION
RIGHT CONDYLE ; WORKING OR ROTATORY SIDE
LEFT CONDYLE ; NONWORKING OR ORBITING SIDE

58. GENERAL ARRAGEMENT OF
TISSUES OF TMJ
H & E; X 3

59. BONY STRUCTURES AND THE CARTILAGE ASSOCIATED WITH THE JOINT
CODYLE OF MANDIBLE COMPOSED OF
CANCELLOUS BONE COVERED BY A THIN
LAYER OF COMPACT BONE.
ROOF OF GLENOID FOSSA IS THIN
COMPACT BONE
ARTICULAR EMINENCE COMPOSED OF
SPONGY BONE COVERED BY A THIN
LAYER OF COMPACT BONE.
ARTICULAR SURFACE COVERED BY FIBROUS TISSUE
UNDERNEATH WHICH IS FIBROCARTILAGE AKA
SECONDARY GROWTH CARTILAGE SEEN IN THE REGION
OF CONDYLE AND ARTICULAR EMINENCE
PROLIFERATIVE ZONE + HYPERTROPHIC ZONES
CREATED
FURTHER ENDOCHONDRAL OSSIFICATION TAKES
PLACE

61. ARTICULAR DISK; INWARD EXTENSION OF CAPSULE FORMS A
TOUGH FIBROUS DISK
DENSE FIBROUS TISSUE CONTAINING
TYPE 1 COLLAGEN FIBRES IS
PRESENT.RARELY TYPE 3 COLLAGEN
BUNDLES MAY ALSO BE PRESENT.
FIBROBLASTS ARE ELONGATED AND SEND
CYATOPLASMIC PROCESSES.LATER STAGES
OF LIFE CELLLS BECOME ROUNDED ARE
ARRANGED IN PAIRS RESEMBLING
CHONDROCYTES.
DISC IS VASCULAR WITH THE
PRESENCE OF NEURAL ELEMENTS IN
THE PERIPHERY BT IN THE CENTRE IT IS
AVASCULAR AND LACKS NEURAL
ELEMENTS.
CAPSULE ; FIBROUS NONELASTIC MEMBRANE CONTAINING NERVE ENDINGS

62. LIGHT MICROSCOPY

63. SYNOVIAL MEMBRANE ; CONSISITS OF INTIMAL CELLS WHICH HAV GAPS
AND SUBINTIMAL CONNECTIVE TISSUE LAYER WITH VASCULARITY..
FIRSTTYPE
RICH IN ROUGH
ENDOPLASTIC
RETICULUM
SYNONYMS;
B CELL,
FIBROBLAST
LIKE CELL,
SECRETORY
CELL
SECONDTYPE
RICH IN GOLGI
COMPLEX AND
LYSOSOMES
AND CONTAINS
LITTLE OR NO
RER
SYNONYMS;
A CELL,
MACROPHAGE
LIKE
THIRDTYPE
CELLULAR
MOSRPHOLOGY
BETWEEN A
AND B CELL.

64. MACROPHAGE LIKE CELL
FIBROBLAST LIKE CELLS
AMORPHOUS
INTERCELLULAR MATRIX

66. TRANSMISSION ELECTRON
MICROGRAPH SHOWING
FIBROBLAST IN THE FIBROUS
ARTICULAR TISSUE COVERING
FIBROBLAST.
FIBROUS TISSUE COVERING
ARTICULAR SURFACES
CHONDROCYTES MAY
BE SEEN !

67. C
O
N
C
L
U
S
I
O
N
AS DENTISTS TMJ IS THE
CLOSEST APPROACH OF A
SYNOVIAL JOINT THAT WE
CAN HAVE.
HENCE THOROUGH
KNOWLEDGE ABOUT THE
JOINT AND ITS FUNCTIONS
HELPS US THROUGH OUR
YEARS IN DENTISTRY.

68.  TENCATE’ S BOOK ON ORAL HISTOLOGY
 ORBANS TEXTBOOK OF ORAL HISTOLOGY
 BD CHAURASIA ,GRAYS ANATOMY
 NALLASWAMY TEXTBOOK OF PROSTHODONTICS
 NEELIMA MALLIK TEXTBOOK OF ORAL SURGERY
 BERKOVITZ A COLOUR ATLAS AND TEXT OF ORAL
ANATOMY , HISTOLOGY AND EMBRYOLOGY
 MAJI JOSE
 WEB PAGES