Skull and Mandible - Review Flashcards

A set of practice questions (Q&A style) covering the skull and mandible topics from the notes, designed to aid exam preparation.

How many bones make up the skull?

22 bones (8 in the cranium and 14 in the facial skeleton).

What are the two main parts of the skull and their functions?

The cranium protects the brain; the facial bones provide facial structure and form the oral/nasal cavities and orbits.

What is calvaria?

The portion of the cranium that surrounds the brain; the calvaria is the cranial vault roof.

Name the eight cranial bones.

Frontal, Occipital, Right Parietal, Left Parietal, Right Temporal, Left Temporal, Sphenoid, Ethmoid.

Which sutures connect the cranial bones and what do they join?

Coronal suture joins frontal with the parietal bones; Sagittal suture joins the two parietal bones; Lambdoid suture joins the occipital with the parietals.

What are fontanelles and where are the two major ones?

Fontanelles are gaps in neonates where sutures are incompletely fused; Frontal fontanelle at the coronal-sagittal junction; Occipital fontanelle at the sagittal-lambdoid junction.

Which five bones form the base of the skull?

Ethmoid, Sphenoid, Occipital, Frontal, and Temporal bones.

Which bone forms the cheekbones?

Zygomatic bone.

Which bone forms the medial wall of the orbit and is one of the smallest facial bones?

Lacrimal bone.

Which bone forms the bridge of the nose?

Nasal bone.

Which bones are the inferior nasal conchae and what is their function?

Inferior nasal conchae; located within the nasal cavity; increase surface area to humidify and warm inspired air.

Which bones form the hard palate?

Maxilla and Palatine bones.

Which bone forms the posterior aspect of the nasal septum?

Vomer.

What is the mandible and its basic description?

The largest and strongest facial bone; the lower jaw with a horseshoe-shaped body that houses the teeth via the alveolar process.

What is the temporomandibular joint (TMJ)?

The hinge-type joint between the mandible (condyle) and the temporal bone (mandibular fossa).

Where is the mental foramen located and what passes through it?

On the external surface of the mandible body, inferior to the second premolar; transmits the mental nerve and vessels.

What are the key features of the ramus of the mandible?

External surface for masseter attachment; inner surface contains the mandibular foramen; lingula near the foramen; posterior border thick; anterior border continuous with the oblique line; mandibular notch separates coronoid and condylar processes; angle at the junction with the body.

What are the three main processes of the mandible?

Alveolar process (houses teeth), Coronoid process (attachment for temporalis), Condylar process (articulation with temporal bone forming the TMJ).

What does the anterior cranial fossa involve regarding the ethmoid bone?

Ethmoid forms the upper nasal cavity and the medial walls of the orbits; crista galli for falx cerebri; cribriform plate foramina transmit olfactory nerves; foramen caecum transmits emissary veins.

What is the sella turcica and which bone contains it?

A saddle-shaped depression on the sphenoid bone that houses the pituitary gland (hypophysis).

Which nerve passes through the optic canal?

Optic nerve (CN II).

Which nerves and vessels pass through the superior orbital fissure?

Ophthalmic nerve (V1), oculomotor (III), trochlear (IV), abducens (VI) nerves and ophthalmic veins.

Which nerve passes through the foramen rotundum?

Maxillary division of the trigeminal nerve (V2).

Which nerve passes through the foramen ovale?

Mandibular division of the trigeminal nerve (V3).

What passes through the foramen spinosum?

Middle meningeal artery.

Where is the carotid canal located and what is its relation to foramen lacerum?

The carotid canal opens in the upper aspect of the foramen lacerum; the internal carotid artery lies just to the side of the body of the sphenoid, above the foramen lacerum.

What bones form the posterior cranial fossa and what marks it?

Formed by the posterior surface of the petrous temporal bone and the occipital bone, with the clivus; marked by dural venous sinuses; contains the internal acoustic meatus for CN VII and VIII; foramen magnum transmits the spinal cord.

Which nerves pass through the jugular foramen?

Glossopharyngeal IX, Vagus X, Accessory XI (spinal portion), and the internal jugular vein.

What is the embryologic origin of the mandible?

Develops from the first pharyngeal arch with Meckel cartilage; Meckel cartilage serves as a template; two halves fuse at the mandibular symphysis during infancy; full fusion by about age one; gonial angle changes from ~160° at birth to ~120° in adulthood.

What is the primary blood supply to the mandible and related vessels?

Inferior alveolar artery (branch of maxillary); peri-mandibular branches of maxillary, facial, external carotid, and superficial temporal arteries; dental branches from inferior alveolar artery.

Where do lymphatics from the mandible primarily drain?

Submandibular lymph nodes; mandibular symphysis region drains to submental nodes.