Anatomy Flashcards
what are the main branches of the trigeminal nerve
opthalmic, maxillary and mandibular
what are the main functions of trigeminal nerve
general sensory to skin on face, tongue and teeth. motor to muscles of mastication
where do the branches of trigeminal exit the skull
opthalmic - supraorbital fissure
maxillary - foramen rotundum through pterygopalatine fossa to exit through the infraorbital fissure
mandibular - foramen ovale through infratemporal fossa to exit through the mental foramen
where do the nerve roots of trigeminal originate from
mesencephalic nucleus - proprioception - midbrain
chief sensory nucleus - general touch - pons
spinal nuclei - pain and temperature - medulla
where does the trigeminal ganglion lie
on the apex of the petrous temporal bone - meckel’s cave
describe the course of the opthalmic branch of trigeminal
from trigeminal ganglion, runs anteriorly along lateral border of cavernous sinus to exit through the supra orbital fissure
what are the branches of opthalmic branch
frontal - supra orbital, supra trochlear
lacrimal - one nerve
nasociliary - anterior and posterior ethmoidal nerves, external nasal, long ciliary nerves, infra trochlear
why might shingles on the nose be a problem
this virus lives in nerves, therefore, as the same nerve supplies the nose and the cornea, the virus could get into their eye
describe the course of the maxillary branch of the trigeminal nerve
runs along the lateral border of the cavernous sinus anteriorly. runs through the foramen rotundum, enters teh pterygopalatine fossa, reaches the infraorbital fissure - exits skull and branches
what are the branches of the maxillary branch of trigeminal
zygomatic - zygomatic-facial, zygomatic-temporal
infra-orbital - anterior and middle superior alveolar nerve
posterior superior alveolar, greater and lesser palatine nerves, nasopalatine
what nerves innervate the teeth and gingiva of maxillary
teeth - anterior, middle and posterior superior alveolar
gum - buccal - anterior middle and posterior superior alveolar
lingual - greater palatine at posterior, nasopalatine anteriorly
describe the course of the mandibular division of the trigeminal nerve
through foramen ovale, through infratemporal fossa where it branches, and posterior branch can run down mandible through mental foramen
what are the boundaries of the infratemporal fossa
lateral - ramus of mandible
medial - lateral border of ptergoid plate of sphenoid
superior - infratemporal crest of sphenoid
inferior - angle of mandible
anterior - posterior border of mandible
posterior - tympanic plate or mastoid
what branches come off mandibular nerve prior to anterior and posterior trunks
meningeal nerve - dura mater, sensory
tensor tympani - muscle in ear controlling vibrations
tensor palatini - elevates soft palate
nerve medial ptergoid muscle - elevates and rotates mandible
what are the nerves branching from anterior trunk of mandibular branch of trigeminal nerve
masseteric nerve - masseter muscle
deep temporal nerve - temporalis
nerve to lateral pterygoid muscle - depresses mandible
buccal nerve - sensory innervation to cheek, mucosa and gingiva
what are the nerves branching from posterior trunk of mandibular branch of trigeminal nerve
auriculotemporal nerve
lingual nerve - sensory innervation to mucosa, gingiva and skin
inferior alveolar nerve - sensory innervation to all mandibular teeth, motor innervation to mylohyoid and anterior belly of digastric
what are the branches of inferior alveolar nerve
motor - branches just before entering mandible - innervation to mylohyoid and anterior belly of digastric
sensory - main trunk to posterior teeth
anteriorly divides into incisive nerve and mental nerve
incisive - anterior teeth
mental - sensory to anterior mucosa, and gingiva
what nerves supply the tongue
anterior 2/3rds - general somatic - lingual nerve of posterior trunk of mandibular branch of trigeminal nerve,
special sensory - facial nerve - chordi tympani
posterior 1/3rd - glossopharyngeal nerve
what structures arise from the 1st pharangeal arch
trigeminal nerve, muscles of mastication, meckel’s cartilage (forming mandible)
what are the 5 prominences essential in facial development
frontonasal - forehead, covering forebrain
medial and lateral nasal prominence - midline of nose and alae of nose
maxillary prominence - cheeks and upper lip
mandibular prominence - lower lip and jaw
what develops from the medial nasal prominence and what does this go on to form
intermaxillary process - important for philtrum of lip and primary palate (as secondary is forming)
what structure does the maxillary process give rise to
palatal shelves - these grow downwards from maxillary prominence and then forwards, until they meet at midline and fuse to form secondary palate
how does a cleft lip and a cleft palate
cleft lip - failure of fusion between intermaxillary process (nasal prominence) and the maxillary prominence
cleft palate - failure of fusion of palatal shelves
what are some differences between adult and fetus skulls
fetus - presence of fontanelles, sutures not completely fused, obtuse angle of mandible, tympanic ring instead of plate
what fontanelles are present in a fetus
anterior, posterior, 2 sphenoid, 2 mastoid
what sutures are present
coronal, sagital, lamboidal