1. SKULL

2. HUMAN SKULL Consists of 22 bones (also 6 tiny bones in the middle ear)
8 of these bones make up the cranium
14 form the facial skeleton.

3. PARTS OF THE SKULL: CRANIUM
The cranium encloses and protects the brain, and its surface provides attachments for muscles that make chewing and head movements possible.
There are 8 bones that make up the cranium.
Frontal Bone
Parietal Bones (2)
Occipital Bone
Temporal Bones (2)
Sphenoid Bone
Ethmoid Bone

4. FRONTAL BONE Frontal Bone
Forms the anterior portion of the skull above the eyes, including the forehead, the roof of the nasal cavity and roof of the orbits of the eyes.

5. Parietal Bones Parietal Bones
The parietal bones (2) form, by their union, the sides and roof of the cranium.

6. Occipital Bone Occipital Bone
The occipital bone joins the parietal bones.
It forms the back of the skull and the base of the cranium.
A large opening on its lower surface houses nerve fibers from the brain that pass to the spinal cord.

7. Occipital Bone

8. Temporal Bones
The Temporal bones (2) one on each side of the skull joins the parietal bone along a squamosal suture.
Forms the sides and the base of the cranium.
Houses the internal ear.
Notice how far it goes around the face before it meets the zygomatic bone “cheek”

9. Temporal Bones

10. Sphenoid Bones
The sphenoid bone is wedged between several other bones in the anterior portion of the cranium.
Helps form the base of the cranium, the sides of the skull and the floors and sides of the orbits.
This bone really has three different views:
Lateral—anterior to the temporal bone
Anterior- the back of the eye sockets
Inferior- looks like a butterfly.

11. Sphenoid Bones This bone really has three different views…
Lateral—anterior to the temporal bone
Anterior- the back of the eye sockets
Inferior- looks like a butterfly.

12. Sphenoid Bones (Inferior View)

13. Ethmoid Bone Located in front of the sphenoid bone.
Forms part of roof and walls of nasal cavity.
Floor of cranium, and walls of orbits.
In the back of the orbital cavity…longer bone
Forms the upper portion of the nasal septum

14. Ethmoid Bone

15. Facial Bones The facial consists of 14 bones
These bones provide basic shape of the face
Attachments for muscles that move the jaw and control facial expressions.

16. MANDIBLE Lower jaw bone
Only moveable bone held to the cranium by ligaments.
Horseshoe-shaped body with a flat ramus projecting upward at each end

17. MANDIBLE

18. MAXILLARY BONES They form the upper jaw.
Together they form the keystone of the face.
They form anterior roof of mouth, floors of orbits, and floor of nasal cavity.
Contains alveolar process, maxillary sinuses, palatine process.

19. Maxilla

20. Palatine Bones Palatine Bones
The L-shaped palatine bones are located behind the maxillae.
The horizontal portions form the posterior section of the hard palate and the floor of the nasal cavity.
The perpendicular portions help form the lateral walls of the nasal cavity.
This is easier to see from the bottom view of the skull.

21. Palatine Bones

22. ZYGOMATIC BONES
Responsible for the prominences of the cheeks below and to the sides of the eyes.
Help form the lateral walls and the floors of the orbits.
Again notice where it meets the temporal bone…called the Zygomatic Arch or the Zygomatic process of the Temporal

23. Zygomatic Bones

24. Lacrimal Bones Lacrimal Bones
A thin, scalelike structure located in the medial wall of each orbit between the ethmoid bone and the maxilla.
A groove in its anterior portion leads from the orbit to the nasal cavity, providing a pathway for a channel that carries tears from the eye to the nasal cavity.

25. Lacrimal Bones

26. Nasal Bones NASAL BONES
The nasal bones are long, thin, and nearly rectangular.
They lie side by side and are fused at the midline, where they form the bridge of the nose.
These bones are attachments for the cartilaginous tissue that forms the shape of the nose.

27. Nasal Bones

28. Vomer bone
Vomer Bone
The thin, flat vomer bone is located along the midline within the nasal cavity.
Posteriorly, it joins the perpendicular plate of the ethmoid bone
Together they form the nasal septum.

29. Vomer Bone

30. Inferior nasal conchae
Inferior Nasal Cavity
Inferior nasal conchae
The inferior nasal conchae are fragile, scroll-shaped bones attached to the lateral walls of the nasal cavity.
Positioned below the superior and middle nasal conchae of the ethmoid bone.

31. Inferior nasal conchae

33. Foramen
Foramen- An opening through a bone that usually serves as a passageway for blood vessels, nerves, or ligaments.
You need to be able to identify the following…
Mental Foramen, Supraorbital Foramen
Infraorbital Foramen, Foramen Magnum

34. Foramen Supraorbital foramen (notch) Infraorbital foramen Mental

35. Foramen
Foramen magnum

36. Sutures Suture- an interlocking line of union between bones
You need to be familiar with the following sutures….
Coronal Suture,
Lambdoidal Suture
Squamosal Suture
Sagittal Suture

37. Sutures
Coronal suture
Squamous suture
Lambdoid
suture

38. Sutures
Sagittal suture
Lambdoid
suture

39. Process Process- a prominent projection on a bone
You need to familiar with the following…
Styloid Process
Mastoid Process
Coronoid Process

40. Process
Mastoid process
Styloid process
Coronoid
process

41. Condyle
Condyle- is a rounded process that usually articulates with another bone
You need to be familiar with the following…
Mandibular Condyle
Occipital Condyle

42. Condyle
Mandibular
condyle

43. Condyle
Occipital
condyle

44. Inferior View
Palatine bone
Zygomatic bone
Sphenoid bone
Vomer

45. For Your Information Zygomatic process (Aka zygomatic arch
External acoustic canal

46. What have we learned so far??
Coronal Suture
Frontal Bone
Sphenoid Bone
Parietal Bone
Ethmoid Bone
Temporal Bone
Lacrimal Bones
Lamboid
suture
Squamous suture
Nasal Bone
Occipital bone
Zygomatic Bone
Maxilla
External Auditory Canal
Mastoid Process
Mandible
Styloid Process
Mandibular
condyle
Mental Foramen
Coronoid
process 46