2a. facial bones, bony orbit

list the facial bones

nasal, lacrimal, palatine, maxilla, zygoma, inferior nasal conchae, vomer, mandible

how many maxillary bones

2

describe the maxilla

largest immoveable bones of the face, fuse at midline, contribute to the hard palate and the bony orbit

describe the body of the maxilla; where is it found, what structure does it contain

this is the central portion that lies lateral to the nose, contains maxillary sinuses

describe the zygomatic process of the maxilla (ie location)

projects laterally from the body and unites with the zygomatic bone

what is the alveolar process/ridge

the inferior aspect of the body, forms the tooth sockets

what is the frontal process of the maxilla

aka the nasal process, projects upwards along the lateral border of the nose towards the frontal bone

describe the palatine process of the maxilla

forms most of the hard palate, they project horizontally and posteriorly to join the palatine bones

describe the anterior nasal spine of the maxilla; what is it formed by

formed anteriorly by the fusion of the palatine processes

what does the maxilla articulate with

nasal bones, lacrimal bones, ethmoid bone, palatine bones

how many zygomatic bones are there

2

describe the zygomatic bones

form the prominence of the cheeks, contribute to the lateral and inferior walls of the bony orbit

list the components of the zygomatic bone

4 processes: maxillary, frontal, temporal, orbital

describe the maxillary process of the zygomatic bone

articulates anteriorly with the maxilla

describe the frontal process of the zygomatic bone

thick and serrated, articulates with the frontal bone and sphenoid

describe the temporal process of the zygomatic bone

long, narrow, serrated, joins with the temporal bone posteriorly to form the zygomatic arch

describe the orbital process of the zygomatic bone

forms part of the lateral and inferior wall of the orbit, articulates with the greater wing of the sphenoid

what bones does the zygomatic bone articulate with

zygomatic process of the temporal bone, maxilla, frontal bone, sphenoid bone

describe the mandible

largest and strongest facial bone, forms the oral cavity, provides structural support for the lower face, enables functions like chewing/speaking/facial expression

list the two main parts of the mandible

horizontal body, two vertical rami

describe the body of the mandible

horseshoe shaped, forms the lower jaw

what is the alveolar process of the mandible

part of the body, these are the sockets for the lower teeth

describe the rami of the mandible

makes up the vertical portion

what are the mandibular angles

formed by the junction of the rami and body

what is the coronoid process of the mandible

anterior process of the rami

what muscles attach to the coronoid process of the mandible

temporalis, masseter

what is the condyloid process/condyle of the mandible

posterior part of the rami, forms the TMJ

what makes up the TMJ

condylar process of the mandible, temporomandibular fossa of the temporal bone

what is the mandibular notch

separates the coronoid process and condylar process

what is the mental foramen

small hole on the mandibular body that serves as a passageway for nerves and blood vessels

what is the mental protuberance

the chin

what bones does the mandible articulate with

temporal bones (=TMJ), upper incisors of the maxilla

how may palatine bones

2

describe palatine bones

small, L shaped, located at the posterior aspect of the nasal cavity (between the maxilla and pterygoid process of the sphenoid)

list the 3 components of the palatine bones

horizontal plate, vertical/perpendicular plate, orbital process

structurally, what is the pterygopalatine fossa

the space between the sphenoid, maxilla, and palatine bones

what structures/vessels does the pterygopalatine fossa contain

maxillary nerve, pterygopalatine ganglion, and part of the maxillary artery

the maxillary nerve is a branch of which cranial nerve

trigeminal

describe the orbital process of palatine bones

forms part of the posterior orbital wall

describe the vertical/perpendicular plate of palatine bones

forms part of the posterior lateral wall of the nasal cavity

describe the horizontal plate of palatine bones

forms the posterior third of the hard palate

what bones do the palatine bones articulate with

orbital process with ethmoid and maxilla = medial wall of the orbit, sphenoid and nasal concha = lateral walls of nasal cavity, maxilla = posterior portion of the hard palate

how many lacrimal bones are there

2

describe lacrimal bones

located posterior to the nasal bones and maxilla, they sit on the medial wall of each orbit

list the components of the lacrimal bones

lacrimal groove nasolacrimal foramen

describe the lacrimal groove

this is a groove where the lacrimal bone meets the maxilla, and it holds the lacrimal sac

role of the lacrimal sac

collects and drains tears into the nasal cavity

what does the lacrimal bone articulate with superiorly (and what does this form)

frontal bone = part of the orbit roof

what does the lacrimal bone articulate with posteriorly (and what does this form)

ethmoid = part of the lateral wall of the nasal cavity

what does the lacrimal bone articulate with anteriorly and inferiorly (and what does this form)

maxilla = lacrimal groove

how many nasal bones are there

2

describe nasal bones

small, irregularly shaped, form the bridge of the nose, fuse at midline, serve as an attachment point for nose cartilage

what do the nasal bones articulate with superiorly

frontal bone

what do the nasal bones articulate with posteriorly

ethmoid

what do the nasal bones articulate with medially

the opposite nasal bone

what do the nasal bones articulate with laterally

maxilla

how many vomer bones are there

1

describe the vomer

forms the inferior part of the bony nasal septum, midline

list the components of the vomer

body (vertical plate), 4 borders: superior, inferior, anterior, posterior

what does the vomer articulate with anteriorly

septal cartilage

what does the vomer articulate with posteriorly

perpendicular plate of the ethmoid, sphenoid bone

what does the vomer articulate with laterally

maxilla, palatine bones

describe the inferior concha

scroll-like, they help divide the nasal cavity into 3 passageways (superior, middle, and inferior meatus)

list the components of the inferior concha

curved lamina (body), process: lacrimal, ethmoidal, maxillary, palatine

role of the meati formed by the inferior concha

direct airflow, condition air by trapping particles, warm air, humidify air

describe the bony orbit

cone-shaped cavities formed by a combo of facial and cranial bones, they enclose/protect the eye + extraocular muscles + nerves + blood vessels

what bones (and their components) form the roof of the bony orbit

frontal bone (orbital plate), sphenoid bone (lesser wing)

what bones form the medial wall of the bony orbit

maxilla, lacrimal bone, ethmoid, sphenoid body

what bones form the lateral wall of the bony orbit

zygomatic bone, sphenoid (greater wings)

what bones form the floor of the bony orbit

maxilla, zygomatic bones, palatine bones

what bones form the posterior wall of the bony orbit

sphenoid

name the foramen found in the base of the bony orbit

infraorbital foramen

role of the infraorbital foramen

gives passage for the infraorbital nerve + blood vessels

the floor of the bony orbit is also the roof of which structure

maxillary sinuses

describe the medial wall of the bony orbit

thinnest portion, made of the lacrimal bone + maxilla + frontal bone + ethmoid. contains the lacrimal groove

describe the posterior wall of the bony orbit

contains the sphenoid, ethmoid, and palatine bones

describe the lateral wall of the bony orbit

thickest portion, made up of the greater wing of the sphenoid + frontal process of the zygomatic

describe the optic foramen of the bony orbit

small opening in the sphenoid bone, lies 37 degrees to the median plane, this is the entrance to the optic canal

where is the optic canal found within the bony orbit

within the lesser wing of the sphenoid

role of the optic canal

passageway for the optic nerve (CN I) and ophthalmic artery

where is the superior orbital fissure found

between the greater and lesser wings of the sphenoid, located lateral to the optic foramen/canal

role of the superior orbital fissure

gives passage to the oculomotor nerve (III), trochlear nerve (IV), branches of the ophthalmic nerve (which is the first branch of the trigeminal nerve), abducens nerve (VI), and superior/inferior ophthalmic veins

where is the inferior orbital fissure found

between the maxilla, zygomatic bone, and greater wing of the sphenoid. located in the lower part of the orbit

role of the inferior orbital fissure

gives passage to the zygomatic branch of the maxillary nerve, infraorbital nerve + artery + vein