Oral Cavity Flashcards
What does the term prehension mean?
The act of getting food into the mouth
What does mastication mean?
Mechanical breakdown of food using the teeth
What does deglutition mean?
Swallowing (when food passes from the oral cavity to the oesophagus)
What is the correct anatomical term for the lips?
Labia oris - labia superius (upper lip), labia inferius (lower lip)
Where is the vestibule in the oral cavity?
Between the teeth and cheeks
What is the philtrum?
The medial line between two nostrils
Where is the medial sulcus?
- Runs along the medial line of the tongue
- A furrow in the centre of the tongue
Where is the palatine raphe?
Along the medial line of the hard and soft palate
What two structures combine to form the pharynx?
The nasopharynx and the oropharynx
What structure of the buccaneer cavity is unique to the equine head?
The guttural pouch
What are the impacts of brachycephalic breeds on the oral cavity?
- They have an elongates, thickened soft palate
- Suffer from laryngeal collapse
- Narrowing of the trachea
- Have laryngeal saccules which can block the airway
- Stenotic nares
- BOAS
What 4 key muscles are involved in prehension? What does each one do?
- Zygomaticus (opens the mouth)
- Levator labii superioris (elevates the top lip and draws it to one side)
- Buccinator (keeps food between the teeth whilst chewing)
- Orbicularis oris (closes the lips so food and water stay in the mouth)
What is the interdental space?
This is only present in horses, and is the space between the incisors and cheek teeth (good for bit)
What is the dental pad and where is it found?
Found in ruminants. No upper incisors, there is a hard palate there instead.
What does the frenulum do?
Frenulum attaches the body of the tongue to the floor of the oral cavity.
What is the difference between ruminant and pig tongues and the tongues of horses and dogs
- Horses and dogs have a U shaped tongue
- Ruminant and pigs have a V shaped tongue
What is the torus linguae and what does it do?
It is a swelling in the tongue which pushes food against the hard palate
What are the 6 functions of the tongue?
1) Grooming
2) Lapping
3) Prehension
4) Manipulation
5) Deglutition
6) Vocalisation
Where are the intrinsic muscles of the tongue? What is their function?
- Intrinsic muscles found inside the tongue
- There are dorsal and ventral longitudinal muscles
- These muscles shorten, flatten and narrow the tongue
What are the 4 extrinsic muscles of the tongue?
1) Styloglossus
2) Genioglossus
3) Hyloglossus
4) Geniohyoideus
For each of these 4 extrinsic muscles, where are they and what do they do?
- Styloglossus retracts and elevates the tongue (attaches to the styloid bone)
- Genioglossus protrudes and depresses the tongue (attaches to the chin)
- Hyloglossus retracts and depresses the tongue (attaches to the hyoid apparatus)
- Geniohyoideus pulls the tongue forward (attaches to hyoid)
For each of these 4 extrinsic muscles, where are they and what do they do?
- Styloglossus retracts and elevates the tongue (attaches to the styloid bone)
- Genioglossus protrudes and depresses the tongue (attaches to the chin)
- Hyloglossus retracts and depresses the tongue (attaches to the hyoid apparatus)
- Geniohyoideus pulls the tongue forward (attaches to hyoid)
What is the lyssa?
A cartilaginous bone medially on the ventral side of the tongue apex
It is used to curve the tongue and facilitate prehension/ lapping
What nerve is responsible for movement of the tongue?
Hypoglossal nerve
What nerve links to the senses of the tongue?
Trigeminal nerve
What nerve controls taste senses in the tongue?
Glossopharangeal nerve
What is the main blood vessel in the tongue?
Lingual artery
What are the 5 types of papillae found on the tongue?
1) Conical (Mechanical)
2) Foliate (Gustatory)
3) Valiate (Gustatory)
4) Fungiform (Gustatory)
5) Filiform (Mechanical)
What are the 4 major salivary glands in the oral cavity?
1) Parotid
2) Mandibular
3) Sublingual
4) Zygomatic
Where is the parotid gland found?
Found at the base of the ear
Where is the mandibular gland found?
- Sits ventral to the parotid gland
- Gland comes in under the tongue
Where is the zygomatic gland found?
- Found between the mucosa and buccal muscles
- Duct opens into the vestibule
- Sits around the zygomatic arch of the skull
What are the 3 minor salivary glands in the oral cavity?
Palatine
Lingual
Buccal (duct opens into the vestibule)
What are the 5 functions of saliva
1) Lubricates ingested feed and helps form a bolus
2) Contains amylase for starch digestion
3) Has antimicrobial properties
4) Contains sodium bicarbonate and electrolytes
5) Protects oral mucosa
How does the autonomic nervous system affect activity of the oral cavity?
- Activity of the sympathetic nervous system reduces saliva production and causes vasoconstriction
- Activation of the parasympathetic nervous system increases saliva production and causes vasodilation
What nerves are involved in saliva production?
Facial, Glossopharangeal, Trigeminal
