1. Skull D.Rania Gabr D.Sama

2. Objectives Identify the different bones forming the skull with important foramina. Differentiate between the bony features of the skull of an adult and infant.

3. The Skull It consists of flat and irregular bones Divides into: Cranial bones which encase the brain Facial bones which form the bones of the face The following must be identified: Nasion Inion Bregma Lambda External occipital protuberance Parietal eminence Zygomatic arch

4. Cranial bones include: (Neurocranium) Frontal Ethmoid Sphenoidal Occipital Parietal Temporal Facial bones include: (Viscerocranium) Maxilla Zygomatic Nazal Palatine Lacrimal Inferior concha Vomer Mandible The Skull

5. Frontal Maxilla Zygomatic Nazal Mandible Lacrimal

6. The Skull Parietal Temporal Squamous Mastoid Styloid Tympanic Petrous Sphenoid Greater wing Lesser wing Pterygoid process Body Occipital

7. The Skull Petrous part of temporal Lesser wing of sphenoid Body of sphenoid Pterygoid process Ethmoid bone Crista galli Cribriform plate Perpendicular plate Vomer Palatine bone

8. Cranial Fossa It is the cavity of the skull Divides into: Anterior cranial fossa Middle cranial fossa Posterior cranial fossa

9. Anterior Cranial Fossa Formed of: Orbital plate of frontal bone Cribriform plate of ethmoid Crista galli Lesser wing of sphenoid Occupies: Frontal lobe of the cerebrum Optic nerves Olfactory bulb and tract

10. Middle Cranial Fossa Formed of: Greater wing of sphenoid Body of sphenoid Squamous part of temporal bone Anterior part of petrous bone It occupies: Temporal lobe of the cerebrum

11. Posterior Cranial Fossa Formed of: Sphenoid part of clivus Posterior part of petrous bone Occipital bone It shows the following land marks: Groove for transverse sinus Groove for segmoid sinus Internal occipital protuberance It occupies: Cerebellum Brain stem

12. Base of The Skull Most of the bones are seen in other views Fracture base of the skull why?

13. Foramina of the Skull Foramina are found within the skull bones They vary in size and shape They transmit nerves, blood vessels and dura matter

14. Foramina of the Skull

15. Supraorbital Infraorbital Mental

16. Sutures of the Skull Sutures are fibrous joints articulating the skull bones They include: Coronal Sagittal Lambdoid Pterion

17. Skull Fontanel Fontanels are spaces between some of the skull bones of infants They permit easy growth of the brain They permit overlapping of skull bones during labor They are anterior, posterior, anterolateral, and postero- lateral They close later in life at 6-18 months

18. The Mandible It is a flat bone Identify the following: Head(condylar process) Mandibular notch Coronoid process Ramus Angle Body Mylohyoid line Submandibular fossa Digastric fossa Mandibular foramen Mental foramen