Norma lateralis

1. The Lateral View of the Skull Norma Lateralis

2. The Bones Involved in Norma Lateralis Temporal Bone Parietal Bone Occipital Bone Frontal Bone Zygomatic Bone Maxilla Mandible Nasal Bone Sphenoid Bone Lacrimal Bone.

3. The Two Divisions of the Skull in Norma Lateralis Cerebral Portion - located above the zygomatic arch. Facial Portion - located below the zygomatic arch.

4. The Characteristic Features of the Cerebral Portion

5. Temporal Lines Supramastoid Crest Temporal Fossa Zygomatico -temporal foramen Zygomatic arch Infratemporal fossa Suprameatal triangle Pterion Asterion .

6. Pterion - the thinnest part of the lateral wall of the skull. - an important area because it overlies the anterior division of the middle meningeal artery and vein.

7. - point where the posteroinferior angle of the parietal bone meet the occipital bone and the mastoid part of the temporal bone. Asterion

8. The Characteristic Features of the Facial Portion

9. Zygomatic arch Articular tubercle External acoustic meatus Mandibular fossa Styloid process Mastoid temporal Mastoid process Mastoid foramen Gonion .

10. 10. Pterygo -maxillary fissure 11.Pterygo-palatine fossa 12.Spheno-palatine foramen.

11. The Temporal Bone

12. 1. Squamous part 2. Mastoid part 3. Tympanic part 4. Petrous part Four Parts of the Temporal Bone

13. The Three Fossae in Norma Lateralis Temporal Fossa Infratemporal Fossa Pterygopalatine Fossa

14. The Temporal Fossa

15. A flat, fan-shaped depression on the lateral surface of the skull. Bones involved: Zygomatic Bone Frontal Bone Greater Wings of Sphenoid Temporal Bone Parietal Bone

16. Boundaries of the Temporal Fossa

17. Boundaries Structure Superior Inferior Temporal Line Anterior Frontal Process of Zygomatc Bone Medial Surface of parietal bone,Temporal Bone , frontal bone and GWS

18. Lateral Zygomatic Arch Inferior Infratemporal Crest of Sphenoid Bone Posterior Inferior Temporal line

19. Temporalis muscle is attached to its floor. Pterion – a small circular area where the frontal, parietal, sphenoid, and temporal bones are close together. Contents of the Temporal Fossa

20. The Infratemporal Fossa

21. A paired depression that is inferior to anterior part of the temporal fossa . Divided from the temporal fossa by the crest of the greater wings of sphenoid.

22. Boundaries of the Infratemporal Fossa

23. Boundaries Structure Superior Greater wings of sphenoid Anterior Maxillary tuberosity Medial Lateral pterygoid plate

24. Lateral Mandibular ramus and zygomatic arch Inferior No border Posterior No border

25. The mandibular division of the trigeminal nerve, Contains pterygoid plexus and the pterygoid muscles, Maxillary artery and its branches, middle meningeal artery, Inferior alveolar artery, Posterior alveolar artery. Contents of the Infratemporal Fossa

26. The Pterygopalatine Fossa

27. A cone-shaped depression, deep into the infratemporal fossa.

28. It is located between the pterygoid process and the maxillary tuberosity near the apex of the orbit.

29. Boundaries of the Pterygopalatine Fossa

30. Boundaries Structure Superior Inferior surface of the body of the sphenoid Anterior Maxillary tuberosity Medial Vertical plate of the palatine bone

31. Boundaries Structure Lateral Pterygomaxillary fissure Inferior Pterygopalatine canal Posterior Pterygoid process of the sphenoid bone

32. Maxillary artery and its branches, Pterygopalatine ganglion, Maxillary nerve. Contents of the Pterygopalatine Fossa

33. The Temporomandibular Joint

34. - is a complex articulation of the movable mandible and the base of the skull. Articulation takes place in two areas: Between maxillary and mandibular teeth ( interjaw dental occlusion ), and Between the mandibular condyle and the temporal bone.

35. Bones Involved in the TMJ Condylar process or condyle of the mandible Mandibular fossa Articular emminence of the temporal bone

36. Components of the TMJ

37. Articular or Fibrous Capsule Temporo-mandibular (lateral) Ligament

38. 3. Articular Disc 4. Joint Cavities

39. 1. Articular or Fibrous Capsule

40. - encloses the joint surfaces like a sleeve that runs from the temporal bone superiorly, to the condyle of the mandible inferiorly. The enclosed space between the articular surfaces is the joint cavity

41. Superior attachment : area surrounding the mandibular fossa and articular eminence of the temporal bone. Inferior attachment: periphery of the mandibular condyle .

42. 2. T emporomandibular (lateral) Ligament

43. - is a lateral thickening of the joint capsule and is similar to the collateral ligaments of other joints. - It prevents posterior and inferior displacement of the condyle but allows limited anterior movements of the condyle .

44. 3 . Articular Disc

45. - it is composed of dense fibrous tissues and lies within the joint capsule, intervening between the condyle and the mandibular fossa . - It is a biconcave disc that serves to provide reciprocal articular surfaces between its inferior surface and the condyle , and its superior surface and the mandibular fossa and eminence.

46. Three zones of the articular disc: Posterior thickening – sits atop the condyle and fills the mandibular fossa above when the mandible is at rest . Anterior thickening - lies just below the posterior slope of the articular eminence . Intermediate zone - lies between the two previous zones.

47. 4. Joint Cavities

48. The disc effectively divides the joint cavity into two distinct upper and lower compartment that allow two types of joint movements. These cavities are also filled with synovial fluid which nourishes the articular disc.

49. Joint Cavities

50. Accessory Ligaments

51. Two accessory ligaments span the joint but do not significantly limit mandibular movements: Sphenomandibular ligament - it runs from the spine of the sphenoid bone to the lingula of the mandible . Stylomandibular ligament - it runs from the styloid process of the temporal bone to the angle of the mandible.

52. The Synovial Membrane

53. A layer of synovium lines the inner aspects of the joint capsule. This relatively dense membrane does not line the actual articular surfaces of the joints because synovial joints are generally weight-bearing joints. The pressure in the TMJ is provided by the occluded maxillary and mandibular teeth. Synovium secretes synovial fluids for lubrication and nourishment of the opposing articular surfaces.

54. An intimal cellular layer - contains type A cells which are phagocytic , and type B cells which synthesize hyaluronate found in synovial fluid . A vascular subintimal layer - Contains blood vessels, and lymphatics within the loose connective tissue matrix. Two Layers of the Synovial Membrane

55. Nerve Supply of the TMJ

56. Branches of the temporalis N . Branches of the auriculotemporal N . Branches of the masseteric N.

57. Blood Supply of the TMJ

58. Superficial temporal artery Muscular branches of the maxillary artery

59. Temporomandibular Joint in Action

60. Muscles Acting on the TMJ

61. Masseter Temporalis Lateral Pterygoid Medial Pterygoid

62. Protrussion : 1 . Lateral pterygoid m. 2. Medial pterygoid m.

63. Retraction Temporalis M. Synergists: Masseters Digastric Geniohyoid

64. Elevation Temporalis Masseter Medial pterygoid

65. Depression Lateral pterygoid Synergists: Digastric Geniohyoid Mylohyoid

66. Lateral movements Medial pterygoid m. Lateral pterygoid m.