Miranda Kadis, Divya Agarwal, Max Lee

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 Functions: 1. Protect the brain 2. Support delicate sense organs involved with vision, hearing, balance, olfaction and gestation 3. Eating (Jaw) 4. Aid with sensory information (eyes, ears, nose, mouth) 5. Aid with communication (mouth, facial expressions)

1. Frontal – air filled to make the bone lighter; produces muscous to clean and moisten nasal cavities 2. Ethiodal - lightens ethiodal bone 3. Sphenoidal – lightens sphenoidal bone 4. Maxillary – lighten the portion of the maxillary bones above the embedded teeth.

 forms forehead and roof of orbits (body recesses that contain eyes)  Supraorbital foramen - opening that pierces ridge above each orbit forming passageway for blood vessels and nerves  above orbit, there are frontal sinuses that make the bone lighter and produce mucus.  infraorbital foramen - opening for a major sensory nerve from the face

 Paired left and right  Posterior to frontal bone  Form roof and superior walls of cranium  Each has a superior and inferior temporal line to which temporal muscle is attached  joined together by midsagittal suture, with the frontal bone anteriorly by coronal suture, with the occipital bone by lambdoid suture, with temporal bone by squamosal and parietomastoid sutures

 forms posterior and inferior portions of cranium  joins two parietal bones at the lambdoid suture  foramen magnum connects cranial cavity with spinal cavity  on either side of this are the occipital condyles - joint between skull and vertebral column

 Below parietal bones  contact parietal bones along the squamous suture on each side  Anatomical landmarks: ○ External acoustic canal leads to the typanum ( eardrum) ○ Eardrum separates external acoustic canal from middle ear cavity which contains ear bones ○ anterior to acoustic canal is a transverse depression ( mandibular fossa) which marks the joint with lower jaw ○ mastoid process is posterior and inferior to entrance to acoustic canal ■ provides a site for attachment of muscles that rotate or extend the head ○ styloid process attached to ligaments that support hyoid bone and anchors muscles associated with tongue and pharynx

 forms part of floor of cranium and unites cranial and facial bones and braces sides of skull  contains pair of sinuses called sphenoidal sinuses

 anterior to sphenoid bone  forms part of cranial floor, contributes to medial surfaces of the orbit of each eye, and forms roof and sides of nasal cavity.  ridge called crista galli projects above superior surface of ethmoid  lateral portions contain ethmoidal sinuses which drain into nasal cavity

 maxillary bones joined with all other facial bones except mandible  form floor and medial portion of rim of orbit, walls of nasal cavity, and anterior roof of mouth  contain maxillary sinuses – lighten portion of bones above teeth  palatine bones form posterior surface of roof of mouth

 inferior margin of vomer joins with palatine bones  supports partition that forms part of nasal septum along with ethmoid bone  one each side of skull zygomatic bones  join with the frontal bone and maxilla to complete lateral wall of orbit

 nasal bone forms bridge of the nose midway between the orbits and joins with the frontal bone and maxillary bones  lacrimal bones within orbit on medial surface  inferior nasal conchae project from lateral walls of nasal cavity

 nasal complex includes bones that form superior and lateral walls of nasal cavities  nasal septum separates left and right portions of nasal cavity  mandible is bone of lower jaw  anterior coronoid process is the attachment point for temporalis muscle (muscle that closes jaw)

 small and u-shaped  ● suspended below skull  ● serves as a base for muscles associated with the larynx, tongue, and pharynx  ● supports and stabilizes portions of larynx

 Common causes: car crashes, collision with object, assaults, falls  Falls most common with children, collisions most common with athletic teens  Head injuries are incredibly dangerous  May lead to permanent disability, mental impairment, or death.

 Concussions: most common (TBI) – brain is shaken hard enough to bounce against skull  Contusion: bruise on the brain that can cause swelling  Hematoma: internal bleeding that causes a clot in the brain  Skull fracture: sometimes a piece of bone may cut the brain and cause internal bleeding

 Sutures=flexi ble joints (fibrous – also known as fontanelles)

 When a baby is growing, the brain grows faster than the skull  At birth: cranial bones are connected by fontanels (“soft spots”)  They permit distortion of the skull without damage

The skull has four joints. Two that attach the mandible to the temporal bone and two that attach the atlas vertebra to the occipital bone. The mandible and occipital condyle joints are hinge joints.