L28a: neuroanatomy of the head

what makes up the skeleton of the head?

1. skull

2. mandible

what are the superficial muscles of the head?

muscle of facial expression, auricular, and oribital

what structures does the skull form?

1. oral cavity

2. nasal cavity

3. paranasal sinuses

4. cranium

cranial foramen

structure allows for exit of cranial nerves from the cranium

what are we typically referring to when we say the rostral part of the skull?

facial part of the skull

what are the paired bones of the cranium?

1. exoccipital

2. parietal

3. frontal

4. temporal

what are the unpaired bones of the cranium?

1. supraoccipital

2. interparietal

3. basioccipital

4. basiphenoid

5. presphenoid

6. ethmoid

what are the paired bones of the face?

1. incisive

2. nasal

3. maxilla

4. dorsal concha

5. ventral concha

6. zygomatic

7. palatine

8. lacrimal

9. pterygoid

10. mandible

what is 1?

lacrimal

what is 2?

frontal bone

what is 3?

parietal bone

what is 4?

occipital bone

what is 5?

temporal bone

what is 6?

sphenoid complex

what is 7?

pterygoid bone

what is 8?

palatine bone

what is 9?

incisive bone

what is 10?

nasal bone

what is 11?

maxilla

what is 12?

zygomatic (cut)

what is hte funciton of the coronoid process in the mandible?

provide attachment point for muscles of mastication

what is the relevance of the angular process of the mandible?

structure palpated on animal during dental nerve block

what structures in the mandible can be used in nerve blocks of the lower teeth?

1. mandibular foramen

2. mental foramina

what is 1?

condyloid process

what is 2?

coronoid process

what is 3?

angular process

what is 4?

body of mandible

what is 5?

mental foramina

what is the 1 by number 6?

ramus of mandible

what forms the skullcap in the horse?

formed mainly by parietal bone

what forms the skullcap in dogs?

formed by temporal and parietal bones

what does the maxilla in the horse have?

prominent facial crest

what is the facial crest in the maxilla of the horse used as a landmark for?

tympanation of the nasal cavity

which species is the orbit that houses the eye complete?

horses

which species is the orbit that houses the eye incomplete?

dogs and cats

what bones is more extensive in forming the skull cap in bovine?

frontal bone

what are the cornual process processes an extension of in bovine?

frontal sinus

what is the cornual process in bovine?

bony extension of the frontal bone; basically the horn

what is the lacrimal bulla in bovine?

fragile pneumatic portion of the lacrimal bone just below the eyes

what is an important landmark in the skull of bovine?

facial tuberosity

what do we use the facial tuberosity in bovine to locate?

infraorbital foramen

foramen orbitorotundum

orbital fissure and round foramen combined

MCQ: list the cranial bones of the skull

1. occipital

2. basisphenoid

3. temporal

4. frontal

5. parietal

MCQ: list the facial bones of the skull

1. nasal

2. maxillary

3. incisive

4. zygomatic

what cranial nerve innervates the facial muscles?

facial nerve (#7)

what cranial nerve innervates the muscles of mastication?

trigeminal nerve (#5)

what action do we associate the superficial muscles of the head with?

facial expression

what action do we associate with the deep muscles of the head?

muscles of mastication

what muscle closes the mouth?

orbicularis oris

what muscle upon contraction will cause the animal to smile?

zygomaticus muscle

what muscle will move the nose and upper lip?

levator nasolabialis

what muscle specific will cause puppy-eye expression in the dog?

levator anguli oculi medialis muscle

what is the function of the levator anguli oculi medialis (LAOM) muscle?

raises the eyebrow to give “puppy dog eyes” expression

what are the groups for the superficial muscles of the head?

1. mouth and nose

2. orbital muscles

3. auricular muscles

what is the function of the scutiform cartilage?

helps muscles with movement of the ear pinna

what are the muscles of mastication?

1. temporalis

2. masseter

3. pterygoideus

4. diagastricus

what is the main muscle of mastication in carnivores?

temporalis muscle

what is the main muscle of mastication in herbivores?

masseter muscle

what is the function of the temporalis and masseter muscles?

closes the jaw by elevating mandible to allow animal to chew

what is the function of the pterygoideus muscle?

1. closing the jaw

2. chewing movements

3. grinding movements

what muscle of mastication allows medial and lateral movements?

pterygoideus muscle

what muscle opens the mouth?

diagastricus muscle

what is the function of the occipitomandibularis in the horse?

synergistic muscle of the diagastric muscle to help open the mouth

MCQ: which muscle closes the eye?

orbicularis oculi