Group 2 Bones of the skull

GROUP 2BONES OF THE SKULLFatin, Aishah, Zafirah, Laila, Masyitah, Amalina, Aimi

BONES OF THE SKULL

SKULL

Facial14 bones

Cranial8 Bones

1 Mandible1 Vomer2 Inferior nasal conchae2 Lacrimal bones2 Maxillae2 Nasal bones2 Palatine bones2 Zygomatic bones

1 Ethmoid bone1 Frontal bone1 Occipital bone2 Parietal bones3 Sphenoid bone4 Temporal bones

FACIAL BONES

CRANIAL BONES

ADDITIONAL SKULL FEATURES

Major sutures Paranasal sinuses Hyoid bone

Major Sutures

Functions TYPE OF

BONEFUNCTIONS

FACIAL

• Form the mechanical framework of the face

• Protect and support entry points of both the digestive and respiratory systems

• Provide attachment for some muscles of facial expression

• Protect and support organs for the senses of vivion, taste, smell, hearing and equilibrium/balance

CRANIAL

• Protection of the brain• Inner-surfaces :attach to membranes

that stabilise the positions of the brain, blood vessels and nerves

• Outer surface : act as areas of attachment for muscles that move the head in various ways

• Protect and support organs for the senses of vivion, taste, smell, hearing and equilibrium/balance

MAXILLA & MANDIBLE

Maxilla Forms the majority of the skeleton of the

face and the upper jaw Contains the maxillary sinus Articulates with the frontal, sphenoid,

nasal, vomer, and ethmoid bones; inferior nasal concha, palatine, lacrimal, and zygomatic bones; and septal and nasal cartilages

Mandible Forms the lower jaw Described as horseshoe shaped All muscles of mastication attach to the

mandible Consists of body of mandible, ramus,

coronoid process, condylar process, alveolar process

LACRIMAL & NASAL BONE

Lacrimal Bone Small and rectangular in shape Very thin and fragile Forms a small portion of medial wall of the orbit Articulates with frontal process of the maxilla,

orbital plate of the ethmoid bone, frontal bone and inferior nasal concha

The region that articulates with the frontal process of the maxilla forms the lacrimal fossa → the location of the lacrimal sac

The inferior part of the lacrimal forms a small portion of the lateral wall of the nasal cavity

Nasal Septum1. Septal Cartilage2. Ethmoid bone3. Vomer

Ethmoid Bone - Perpendicular plate• A flat plate that descend from cribriform

plate to form part of nasal septum• Articulate with vomer inferiorlyVomer• Articulate with perpendicular plate of

ethmoid, maxilla, palatine and sphenoid bone and septal cartilage

• Posterior border no articulation with other bone

Base of Nasal Cavity1. Maxilla – Palatine Process of Maxilla2. Palatine Bone – Horizontal Plate of

Palatal Bone

Maxilla - Palatine Process• Extend medially to form the majority of hard

palate• Articulate with palatine process of opposite side

and horizontal plate of palatine bone• Present of incisive foramenPalatine bone – Horizontal Plate • Form posterior portion of hard palate• Nasal cavity superiorly• On medial part, form by both horizontal plate is

posterior nasal spine• Has greater palatine foramina

Posterior Border of Nasal Cavity

• The center of sphenoid bone

• Anterior portion form part of nasal cavity

• Contain sphenoid paranasal sinuses

Sphenoid Bone - Body

Superior Border of Nasal Cavity1. Nasal Bone2. Frontal Bone3. Ethmoid Bone

• Inferior portion form superior margin of nasal aperture

• Inferior portion of nasal bone attach with lateral nasal cartilage and septal cartilage

Nasal Bone

• Articulate with nasal bone and frontal process of maxilla to form root of nose

Frontal Bone – Nasal Portion

• A horizontal bone that form superior surface of ethmoid

• Contain numerious foramina for olfactory nerves

Ethmoid Bone - Cribriform Plate

Lateral Border of Nasal Cavity1. Ethmoid Bone2. Lacrimal Bone3. Inferior Nasal Concha4. Palatine Plate

• Largest part of ethmoid bone• Descend inferiorly from the cribriform plate• Ethmoid paranasal sinuses located within• Form 2 major structure within nasal cavity

• Superior nasal concha• Middle nasal concha

Ethmoid Bone – ethmoid labyrinth

• Small and rectangular in shape• Inferior part of lacrimal form small portion

of lateral wall of nasal cavity

Lacrimal Bone

• A curved bone that form part of lateral wall of nasal cavity

• Articulate with maxilla and perpendicular plate of palatine, lacrimal, and ethmoid bone

Inferior Nasal Concha

• Shape of vertical rectangle• Superior border is a notch articulate with sphenoid

bone, form sphenopalatine foramen• Form part of lateral wall of nasal cavity

Palatine Bone – Perpendicular plate

FORAMENS OF THE BASE OF THE SKULL

What is foramen?- A foramen (pl. foramina) is an opening.- Foramina allow muscles, nerves, arteries,

veins, or other structures to connect one part of the body with another.

Superior view of

the cranial base

Inferior view of

the cranial base

Foramen Located in or

Formed by

Structures Passing through

Incisive foramen Maxilla

(palatine process)

Nasopalatine n., sphenopalatine a.

Greater palatine foramen Palatine

Greater palatine n. and vessels

Lesser palatine foramina

Lesser palatine n. and vessels

Foramen ovale

Sphenoid

Mandibular division of thetrigeminal n., accessory meningeala., lesser petrosal n., emissary v.

Foramen spinosum

Middle meningeal vessels andmeningeal branch of themandibular division of thetrigeminal n.

Foramen rotundum

Maxillary division of thetrigeminal n.

Sphenoid foramen

Emissary v.Foramen lacerumArticulation of the sphenoid (greater wing

and body), temporal

(petrous portion), and occipital

(basilar portion) bones

Nothing passes through itsphenoid Filled with fibrocartilage duringbody), temporal (petrous life (although the anterior wall of the foramen has an opening for the pterygoid canal and the posteriorwall has an opening for the carotid canal)

Mastoid foramen Temporal (mastoidportion)

Emissary v. (sometimes branches of the occipital a.)

Opening for auditory tube

Temporal and sphenoid

Cartilaginous portion of theauditory tube

Tympanic canaliculus Temporal Tympanic branch of the

glossopharyngeal n.

Jugular foramenTemporal (petrous

portion) and occipital

Glossopharyngeal n., vagus n., spinal accessory n., inferiorpetrosal sinus, sigmoid sinus,posterior meningeal a.

Mastoid canaliculus

Temporal (within the jugular fossa)

Auricular branch of the vagus n.

Petrotympanic fissure

Temporal

Chorda tympani n., anterior tympanic a.

Stylomastoid foramen

Facial n., stylomastoid a.

Tympanomastoid fissure

Auricular branch of the vagus n.Hypoglossal canal

Occipital

Hypoglossal n.Condylar canal Emissary v.,

meningeal branches ofascending pharyngeal a.

Foramen magnum

Medulla oblongata, vertebralarteries, spinal roots of the spinalaccessory n.

Foramen cecum Between the frontal and ethmoid bones

Emissary v. from nasal cavity tothe superior sagittal sinus

Anterior ethmoid foramen

Anterior ethmoid n. and vessels

Posterior ethmoid foramen

Posterior ethmoid n. and vessels

Carotid canal Temporal (petrous portion)

Internal carotid a., internal carotidn. plexus (sympathetics)

Hiatus for the lesser petrosal n.

Lesser petrosal n.

Hiatus for the greater petrosal n.

Greater petrosal n.

Internal acoustic meatus

Facial n., vestibulocochlear n.,labyrinthine a.

Opening of the vestibular aqueduct

Endolymphatic duct

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