1.2 Oral Cavity and Teeth

What is Prehension?

Act of getting food in your mouth. With lips, teeth, tongue, head and jaw movements

What is Mastication?

mechanical breakdown of food and mixing with salvia

What is Deglutition?

Swallowing, voluntary then involuntary

What is the Musculature used in prehension?

1. Zygomaticus

2. Levator Labii superioris

3. Buccinator

4. Orbicularis oris

What does the Zygomaticus do?

Retract the angle of the mouth

What does the levator labii superioris do?

Elevate the upper lip and draw it to one side

What does the Buccinator do?

Keep food between the upper and lower molar teeth during mastication

What does Orbicularis oris do?

Closes the lip and assists in gathering food, drinking and mastication

What is the muscle used for mastication?

Digastricus, Jaw opening

What is the origin and insertion of the Diagatrius muscle?

O:Paracondylar process of the occipital bone

I: Angle of the mandible

What are the Divisions of the Digastric Muscle?

1. Caudal half: innervated by CN VII (facial nerve)

2. Cranial half: Innervated by CN V3 (Trigeminal nerve)

What are the muscles used in Jaw closing?

1. Masseter muscle

2. Lateral pterygoid muscle

3. Medial pterygoid muscle

4. Temporalia or temporal muscle

What is the Masseter muscle?

Closes and protrudes the jaw

What is the Lateral pterygoid muscle?

Protrudes the jaw

What is the medial pterygoid muscle?

Causes one sided contraction to close jaw

What is the Temporalis or Temporal muscle?

pulls mandible dorsally, rostrally (overbite), caudally (underbite)

Where is the Oral cavity located?

From lips to entrance into the larynx

What are the structures of the oral cavity?

1. Tongue

2. Teeth

3. Salivary glands

What is the function of the Hyoid Apparatus?

Holds the larynx in police and supports the pharynx and tongue from the skull

What is the anatomy of the Hyoid Apparatus?

Located in the larynx (voice box) after the pharynx and before the trachea

What are the 5 different bones in the Hyoid Apparatus?

1. Basihyoid

2. Stylohyoid

3. Epiphyoid

4. Keratohyoid

5. Thyrohyoid

What are the PAIRED Cartilages within the Hyoid apparatus?

Arytenoid:

1. Cuneiform

2. Cornicular

3. Vocal

4. Muscular processes

What are the UNPAIRED Cartilages within the Hyoid apparatus?

1. Epiglottis

2. Thyroid

3. Cricoid

What is the function of the cartilage in the Hyoid apparatus?

Part of the laryngeal skeleton, provide rigidity and stability

What does the musculature of the Laryngeal Muscle do?

Elevate or depress the larynx during swallowing ALSO breathing and phonation

What is the musculature of the Laryngeal?

1. Ventricularis

2. Cricoarytenoideus Dorsalis

3. Vocalis

4. Thyroarytenideus

What does Ventricularis do?

Vocal fold addition and glottis constriction

What does the Cricoarytenoideus Dorsalis do?

Abducts the arytenoid cartilage to open glottis

What do the Vocalis do?

Controls vocal cords

What do the Thyroarytenideus do?

Gives rise to ventricularis and vocalis muscle

How is innervation to the larynx provided?

Cranial and caudal laryngeal nerves, origin from vagus nerve

Where are Salivary glands found?

Cheek, tongue, lips, esophagus, soft palate and pharynx

Where are the major salivary glands located?

Away from oral cavity and function through connective ducts

What is the function of the salivary glands?

Produce serous, mucous or mixed secretion

What is the composition of saliva?

1. Water

2. Amylase

3. Sodium bicarbonate

4. Electrolytes

5. Antimicrobial agents

6. Lingual lipase

What is a monostomatic gland?

Deliver saliva to distant side through singular ducts

What is a polystomatic gland?

Produce saliva locally thought multiple openings

What are the major salivary glands?

1. Parotid

2. Mandibular

3. Sublingual

4. Zygomatic

What are the minor salivary glands?

1. Labial

2. Lingual

3. Buccal

4. Palatine

What is sympathetic innervation of the Salivary glands?

Vasoconstriction occurs and flow is decreased (fight or flight)

What is parasympathetic innervation of Salivary glands?

Facial (CN VII) and glossopharyngeal (CN IX) nerve and some branches of trigeminal nerves activated, increase flow (Rest and digest)

What is the function of the tongue?

1. Grooming

2. Lapping

3. Prehension and manipulating food

4. Deglutition reflex

5. Vocalisation

What is the anatomy of the tongue?

1. Fills oral cavity

2. Mobile

3. Supported by hyoid bone

What are the different anatomical parts of the tongue?

1. Root

2. Body

3. Apex

What is Lyssa on a tongue?

Thick cartilage that allows to form structures (cup) to drink water

What are the intrinsic muscles of the tongue?

Dorsal and ventral longitudinal muscle

What are the extrinsic muscles of the tongue?

1. Stylogosus

2. Genioglossus

3. Hyoglossus

4. Geniohyoideus

What does styloglossis do?

Retracts and elevate the tongue

What does the genioglossus do?

Protrudes and depresses the tongue

What does the hyoglossus do?

Retracts and depresses the tongue

What do the geniohyoideus do?

Draws the hyoid and tongue forward

What innervates the movement of the tongue?

Hypoglossal nerve

What innervates the sense of temperature and touch of the tongue?

Trigeminal nerve

What innervates the sense of taste in the tongue?

Glossopharyngeal nerve

How is taste detected through taste pores?

Liquid passing by activate taste pores

What is the main artery of the tongue?

Lingual artery

What are Papillae?

little bumps on tongue

What are the types of Papillae?

1. Conical

2. Foliate

3. Vallate

4. Fungiform

5. Filiform

What are Conical papillae?

Mechanical, Caudal ⅓ of tongue, no taste buds,

What are Foliate papillae

Gustatory, caudal ⅓ of tounge, taste buds, absent in ruminats

What are Vallate papillae?

Gustatory, Taste buds and lymphatics

Which animals have circumvallate papillae?

Goat

What are fungiform papillae?

Gustatory, red dots of keratinised epithelium, heat loss in dogs, rostral ⅔ of tongue, taste buds

What are filiform papillae?

Mechanical, not taste buds, very prominent in cats, rostral ⅔ of tongue

Which papillae do horses not have?

Conical

What are Teeth?

Hard, calcified structured in jaws

What is the function of teeth?

1. Mastication

2. Piercing

3. Hunting and defense

Which animals DON'T have teeth?

Birds

How are teeth divided up anatomically?

1. Crown

2. Neck

3. Root

What is HETEROdonty?

Animals with different size and shaped teeth

What do HETEROdonty specialized teeth include?

1. Incisors

2. Canine teeth

3. Premolars

4. Molars

What are carnassial teeth?

4th upper premolar and 1st lower molars. Used for tearing flesh

What are BRACHYdont teeth?

Teeth that erupt and do not grow after that. Carnivores, incisors of ruminant and teeth of pigs (not tusks)

What are HYPSOdont teeth?

Continue to grow after the eruption. Horse, rabbit tusk of pigs

What type of teeth do rabbits have?

Aradicular Hypsodont teeth