1. 2 Divisions Cranium Face
THE SKULL
2 Divisions
Cranium
Face

2. Most complex bony structure
22 bones in all
Mostly flat bones, but not all!

5. Cranial Bones: 8 Friday Find and describe: 1. frontal bone
2. occipital bone
3. sphenoid bone
4. ethmoid bone
5. parietal bones (2)
6. temporal bones (2)

6. Functions of Cranial Bones
Enclose and protect the brain
Attachment sites for head and neck muscles

7. Functions of Facial Bones
1. form framework of face
2. contain cavities for special sense organs
3. openings for food/air passage
4. secure the teeth
5. anchor the facial muscles of expression

8. ALL BONES OF THE SKULL ARE FIRMLY LOCKED IN PLACE BY JOINTS CALLED SUTURES
Four major sutures

9. THE CRANIUM (8) 1 frontal bone 2 parietal bones 2 temporal bones
1 occipital bone
1 sphenoid bone
1 ethmoid bone

10. THE FRONTAL BONE

11. Parietal Bones: Form most of the superior and lateral aspects of the skull
Figure 7.3a

12. Parietal Bones
Curved, rectangular bones forming majority of the cranium
All four major sutures articulate with this bone

13. Look up the 4 major sutures of the skull

15. Parietal Bones and Major Associated Sutures
Four sutures mark the articulations of the parietal bones
Coronal suture – articulation between parietal bones and frontal bone anteriorly
Sagittal suture – where right and left parietal bones meet superiorly
Lambdoid suture – where parietal bones meet the occipital bone posteriorly
Squamosal or squamous suture – where parietal and temporal bones meet

16. Occipital Bone and Its Major Markings
Forms most of skull’s posterior wall and base
Major markings include the posterior cranial fossa, foramen magnum, occipital condyles, and the hypoglossal canal
Figure 7.2b

18. Temporal Bones Lateral sides of the skull
Zygomatic process connects with zygomatic arch
External auditory meatus (external ear)
Styloid process muscle attachment for tongue and neck
Mastoid process neck muscles

19. Temporal Bones
Figure 7.5

20. Sphenoid Bone Spans width of middle cranial fossa
Articulates with all other cranial bones
Three parts greater wing, lesser wing and pterygoid processes
Sella turcica enclosure for pituitary gland

25. Ethmoid Bone Complex shape Nasal cavity and orbital cavity
Cribriform plate roof of the nasal cavity
Crista galli- outermost covering of the brain cover connects here

28. Maxillary Bones
Medially fused bones that make up the upper jaw and the central portion of the facial skeleton
Facial keystone bones that articulate with all other facial bones except the mandible
Their major markings include palatine, frontal, and zygomatic processes, the alveolar margins, inferior orbital fissure, and the maxillary sinuses

29. Maxillary Bone
Figure 7.8b