Head Flashcards
Orbicularis oculi
O: Medial orbital margin, medial palpebral ligament, lacrimal bone.
I: Skin around orbit, superior & inferior tarsal plates.
N: temporal and zygomatic branches of parotid plexus.
Corrugator supercilli
O: medial end of superciliary arch.
I: skin superior to supraorbital margin and superciliary arch.
N: temporal branch of parotid plexus.
Orbicularis oris
O: Maxillae and mandible, modiolus.
I: mucous membrane of lips.
N: Buccal branch of parotid plexus.
Levator labii superioris
O: Infra-orbital margin (maxilla).
I: skin of upper lip.
N: Buccal branch of parotid plexus.
Zygomaticus minor
O: zygomatic bone.
I: skin of upper lip.
N: Buccal branch of parotid plexus.
Zygomaticus major
O: zygomatic bone.
I: modiolus.
N: Buccal branch of parotid plexus.
Buccinator
O: maxilla and mandible (alveolar processes), pterygomandibular raphe.
I: modiolus, orbicularis oris.
N: Buccal branch of parotid plexus.
Muscles contributing to modiolus (their distal attachment)
Buccinator, Zygomaticus major, Levator anguli oris, Risorius, Depressor anguli oris.
Occipitofrontalis
Frontal belly: O: epicranial aponeurosis - I: skin and sc tissue of eyebrows and forehead. N: temporal branch of parotid plexus.
Occipital belly: O: Lateral 2/3 of superior nuchal line - I: epicranial aponeurosis. N: Posterior auricular branch of parotid plexus.
Platysma
O: sc tissue of infraclavicular and supraclavicular regions.
I: mandible, modiolus.
N: cervical branch of CNVII (via parotid plexus)
CNV gives sensory respectively motor Innervation to what?
Sensory via pseudounipolar neurons in trigeminal ganglion to the face, bypassed by motor root via multipolar axons to muscles of mastication.
Main cutaneous branch of nasocilliary nerve
Infratrochlear nerve
Innervation of lacrimal gland
Lacrimal nerve, smallest branch of CNV1, receiving secretomotor fibers from zygomaticotemporal nerve (CNV2).
Innervation of parotid gland
Preganglionic parasympathetic secretomotor fibers (from the glossopharyngeal, tympanic, and lesser petrosal nerves) synapse in the otic ganglion. Postganglionic fibers travel with the auriculotemporal nerve and so reach the gland.
LR6 SO4 AO3
Lateral rectus CNVI, Superior oblique CNIV, All others CNIII.
Innervation of superior rectus and levator palpabrae superioris
Superior division of CNIII.
Innervation of medial and inferior rectus and inferior oblique.
Inferior division of CNIII
Boundaries of parotid region
Superiorly: Zygomatic arch.
Posteriorly: Sternocleidomastoid, external ear.
Medially: Ramus of mandible.
Anteriorly: Masseter.
Inferiorly: Inferior border and angle of mandible.
Contents of parotid region
Parotid gland and duct, parotid plexus, retromandibular vein, external carotid artery, m. Masseter.
Arterial supply to nose
- Anterior and posterior ethmoidal aa. - ophthalmic artery.
- Sphenopalatine a. - maxillary artery.
- Greater palatine a. - maxillary artery.
- Septal branch of superior labial a. - facial artery.
What encloses the parotid gland and from what is it derived from?
Parotid sheath, derived from investing layer of deep cervical fascia.
Where does the parotid duct enter the oral cavity?
It pierces the buccinator and enters the oral cavity through a small orifice opposite to the 2nd maxillary molar tooth.
Innervation of parotid gland and sheath
Parotid sheath: Great auricular nerve (C2. C3) and auriculotemporal nerve. Also innervates overlying skin.
Parotid gland:
Parasympathetic: CNIX supplies presynaptic secretory fibers to otic ganglion. Postsynaptic parasympathetic fibers are conveyed from otic ganglion to gland by auriculotemporal nerve. Stimulation produces thin watery saliva.
Sympathetic: Derived from cervical ganglia through external carotid nerve plexus. Vasomotor, reduces secretion of gland.
Sensory fibers by great auricular and auriculotemporal nerves.
Boundaries of temporal fossa
Posteriorly and superiorly: Temporal lines.
Anteriorly: Frontal and zygomatic bones.
Laterally: Zygomatic arch.
Inferiorly: Infratemporal crest.