Ch. 14 Flashcards
The occipital bone contains which 3 important passageways
- The foramen magnum
- Hypoglossal canals
- Jugular foramen
Where are the hypoglossal canals located? What passes through them?
On the right and left lateral walls of the foramen magnum; the hypoglossal nn (CN XII)
Where are the jugular foramen? What passes through them
Lateral to foramen magnum between occipital and temporal bones; blood draining from the brain to the jugular foramen and the glossopharyngeal n (CN IX)
What is the hole-filled structure of the ethmoid bone? What passes through these holes?
Cribiform plate; the fibers of CN I (olfactory nerve) into the nasal cavity for smell
Inferior to the cribiform plate, the hollow ethmoid bone balloons out to form what?
the medial aspect of each eye orbit (orbital lamina of the ethmoid bone)
What is the depression on the superior surface of the sphenoid that cradles the pituitary gland
hypophyseal fossa/sella turcica
Which bones make up the temporal fossa?
Sphenoid (greater wing), frontal, parietal, and temporal bones
Which fissure is located between the greater and lesser wings of the sphenoid?
Superior orbital fissure
Which nerve runs through the superior orbital fissure? Branch off of what cranial nerve?
Ophthalmic n; trigeminal nerve
What is the extension of the medial pterygoid plate known as?
pterygoid hamulus
Which muscle attaches in the pterygoid fossa
medial pterygoid muscle (muscle of mastication)
What muscle attaches at the lateral surface of the lateral pterygoid plate?
lateral pterygoid muscle (muscle of mastication)
Which feature projects just medial and posterior to the third molars
pterygoid hamulus
Describe the location of the infratemporal space
Just lateral and posterior to the lateral pterygoid plate and just inferior to the temporal bone
which two pairs of foramina in the sphenoid are important to dental professionals
Foramen ovale and foramen rotundum
Which nn. passes through the foramen ovale? Branch of?
mandibular nn; branch of trigeminal
Where is the sphenoidal spine located?
Just posterior to the foramen spinosum
The foramen ovale is just anterior to what small foramen?
Foramen spinosum
Describe the position of the foramen rotundum
Anterior and slightly medial to the foramen ovale
Which nn pass through the foramen rotundum?
Maxillary nn; branch of trigeminal
The maxillary n exits the skull through the foramen rotundum and travels through which space as it gives off branches
Pterygopalatine space
What are the 3 branches of the trigeminal n and through what openings do they travel?
- Opthalmic; superior orbital fissure)
- Maxillary; through the foramen rotundum to the pterygopalatine space
- Mandibular; foramen ovale
The superior portion of the maxilla forms the floor of what fissure?
Infraorbital fissure
Which vessels travel from the brain to the infraorbital fissure, anteriorly through the infraorbital canal, and out the infraorbital foramen
infraorbital nn and vessels
What are the functions of the maxillary sinus (4)?
- lighten the skull
- Give resonance to the voice
- Warm the air we breathe
- moisten the nasal cavity
Where do posterior superior alveolar nn enter the maxilla and sinus lining? Where are these located?
Alveolar canals; posterior and superior to the third molars
What are the 4 processes of the maxilla
Frontal, zygomatic, alveolar, and palatine
The shallow fossa medial to the canine eminence over the root of the maxillary lateral incisor is called what?
Incicive fossa
The fossa lateral and superior to the canine eminence is?
Canine fossa
The dense inner and outer portion of the alveolar processes are called?
Cortical plate
The less dense bone sandwhiched between the inner and outer cortical plate of the alveolare processes is what?
trabecular bone
small n. branches and vessels pass through what type of bone in the alveolar processes to enter all teeth through their apical foramen?
tabecular/spongy bone
What is the thin, compact bony layer that lines the wall of each tooth socket?
lamina dura
What is the line of fusion between right and left palatine processes?
Intermaxillary suture
What is a centrally located opening at the anterior part of the intermaxillary suture? What does this opening transmit?
Incisive foramen; branches of the nasopalatine n and artery
Just posterior to the maxillary alveolar
process of the most posterior maxillary molar is a bulge
of bone called?
Maxillary tuberosity
A notch that separates the maxillary tuberosity of each maxilla from the adjacent pterygoid process of the sphenoid bone is called?
Hamular notch
What is the junction between the palatine processes of the maxillae and the horizontal processes of the palatine bones
Palatomaxillary suture/Transverse palatine suture
What do the greater palatine foramina transmit?
The greater anterior palatal nerves and the descending palatine vessels
What do the lesser palatine foramina transmit?
The middle and posterior palatine nn
The vertical processes of the palatine bones are separated from the pterygoid processes by what space?
The pterygopalatine space
Which muscle of mastication attaches to the zygomatic arch?
masseter
Where does the inferior border of the body of the mandible join the posterior border of the ramus?
The angle of the mandible
What makes up the human chin?
Two mental tubercles and a mental protuberance
The nearly horizontal ledge of bone in the molar region between the external oblique ridge and alveolar process is
Buccal shelf
Which n. is located in the cheek just superior to the buccal shelf?
Buccal n
The mental foramen is usually near the root apex of which tooth? If not, it is usually between which teeth
Mandibular 2nd premolar; between apices of 1st and 2nd premolar
Which n. exits the mental foramen? What is its role?
Mental branch of the inferior alveolar n.; supply the skin on that side of the chin
On X-rays, the mental foramen must be distinguished from what, which is an infection destroying bone near the root apex?
Periapical abscess
Which mandibular process is anterior and more pointed than the other?
Coronoid process
Which mandibular process is bulkier and posterior to the other
Condyloid process
What is located between the coronoid and condyloid?
Sigmoid notch
Where does the lateral pterygoid m attach on the mandible?
pterygoid fovea; the depression in the front portion of the neck of the condyloid process
Where does the head of the mandibular condyle fit?
The articular (glenoid) fossa of the temporal bone
What is the opening on the internal/medial surface of the mandibular ramus that enters into the mandibular canal? Which vessels travel through here?
mandibular foramen; inferior alveolar vessels and nn.
What is a small groove that runs inferior and anterior to the mandibular foramen?
Mylohyoid groove; mylohyoid n rests here
The ___ is a ridge of bone extending from the coronoid process onto the medial surface of the ramus terminating at the ___. The tendon from what muscle attaches here?
temporal crest; 3rd molar; temporalis muscle
The inferior 1/4 of the temporal crest is called what? What is its significance?
Internal oblique line; radiographic landmark importance appearing just below the external oblique line
The ___ is a roughened shallow fossa
distal to the last ___ and bounded medially by the
lowest portion of the ____ and laterally by the
_____.
retromolar fossa; molar; temporal crest; external oblique ridge
The most posterior fibers of ____ attach in the retromolar triangle on a slight ridge of bone called ____
buccinator m; buccinator crest
The ____ extends downward and forward
from the molar region to the genial tubercles; which muscle attaches here?
mylohyoid ridge; mylohyoid m.
The mylohyoid ridge separates which two fossae? ____ is superior, ____ is inferior to the mylohyoid ridge.
Sublingual fossa and submandibular fossa; sublingual; submandibular