Week 7b TMJII and Oral Cavity

Question 1

What type of joint is the Temporomandibular joint (TMJ)?

Answer 1

modified synovial hinge joint

Question 2

What are the Articulating surfaces of the TMJ?

Answer 2

mandibular fossa of the temporal bone & the condyle of the mandible with an articular disc

Question 3

The Movements of the jaw

Answer 3

• up (elevation) / down (depression)
• forward (protraction) / back (retraction)

Question 4

What are the muscles of mastication?

Answer 4

Temporalis
Masseter
Pterygoid muscles
- Lateral Pterygoid
- Medial Pterygoid

Question 5

Where does the Temporalis attach and what does it do?

Answer 5

• from the temporal fossa to the coronoid process of the mandible
• elevates and retracts the mandible

Question 6

Where does the Masseter attach and what does it do?

Answer 6

• from the zygomatic arch to the angle and ramus of mandible
• elevates the mandible

Question 7

Where do the Pterygoid muscles attach and what do they do?

Answer 7

Originate from the pterygoid plates deep in upper posterior oral cavity

Lateral Pterygoid
 to the mediMedial Pterygoid
 to the medial border of the ramus of the mandible

Medial Pterygoid
 to the medial border of the ramus of the mandible
 elevate and protrude mandible

Question 8

Name the parts of the oral region (6 parts)

Answer 8

• Oral cavity
• Teeth
• Gums (gingivae)
• Tongue
• Palate
• Pillars of fauces

Question 9

Functions of the oral cavity

Answer 9

• Passage for food and fluids
  * hold and masticate food
  * collect food prior to swallowing
  * begin digestion of food
• Accessory airway
• Articulation and resonation for speech

Question 10

What are the parts of the oral cavity?

Answer 10

 Roof
◦ Palate & maxillary teeth
 Walls
◦ Lateral: Buccal mucosa
◦ Anterior: Oral fissure & lips
◦ Posterior: Oropharyngeal isthmus
 Floor
◦ Tongue
 Space
◦ oral cavity proper
◦ oral vestibule

Question 11

Oral cavity structures

Answer 11

Vestibule
* The vestibule is the space between the outer (facial) surfaces of the teeth and the lips and cheeks.
Frenulum
* Under your upper and lower lips is a skin attachment called a frenulum, which is a narrow band of tissue, They are responsible for connecting the lips, cheeks and tongue (lingual frenulum) to the alveolar processes.

Question 12

What do the cheeks contain?

Answer 12

muscles, nerves, fat pads and parotid saliva duct

Question 13

What lines the oral cavity?

Answer 13

Mucous membrane (or mucosa) lines the oral cavity and is continuous with the upper digestive tract.

Question 14

What does the mucous membrane contain?

Answer 14

Mucous membrane has many small mucous glands that keep it moist and lubricated.

Question 15

What is the mucosa called where it surrounds the teetch?

Answer 15

gingiva

Question 16

IS the mucosa and ginviva the same all through the oral cavity?

Answer 16

No. The gingiva and the mucosa of the hard palate and tongue are firmer than the mucosa of the lips and cheeks. This is so that these tissues can withstand the abrasion of hard foods more easily

Question 17

What is the palate

Answer 17

• Hard palate and soft palate (soft palate AKA velum)
• Hard palate forms bony roof of mouth – covered with mucosa

Question 18

What is ridge the ridge that extends down the midline of the hard palate called?

Answer 18

palatine raphe – represents the fusion of left and right maxilla

Question 19

What are palatine rugae?

Answer 19

Irregular folds or ridges of connective tissue extending from the anterior of the palate to the area of the first permanent molars  These can be felt easily with the tongue and they assist in speech and mastication.

Question 20

What are Oropharyngeal isthmus (fauces)?

Answer 20

 Area between the oral cavity and pharynx
- contains Palatine tonsils
 Formed by the ‘Pillars of Fauces’
- Palatoglossal arch
- Palatoglossal muscle covered in mucus Membrane
- Palatopharyngeal arch
- Palatopharyngeaus muscle covered in
mucus membrane

Question 21

Lips (labia oris)

Answer 21

• Surround the mouth
• Formed by musculofibrous tissue
  
  • Orbicularis oris muscle and other facial muscles
  • External surface = skin (rich vascular supply)
  • Internal surface= mucus membrane
  • Labial fraenula anchor to gingiva
• Articulation of sound and speech
• Smiling
• Sucking liquids, holding food
• Osculation (kissing shape)

Question 22

Name the salivary glands

Answer 22

Parotid gland
Submandibular gland
Sub-lingual salivary gland

Question 23

What is saliva for and how much do we produce?

Answer 23

◦ cleans & moistens mouth
◦ dissolves food chemicals for tasting
◦ moistens food (for bolus production)
◦ starts digestion (starchy food)
◦ Cleans mouth “mouthwash”

• The body produces approximately 1 - 1.5 litres per day  97- 99.5% water

Question 24

Where is the Parotid gland and what sort of saliva does it produce?

Answer 24

• Lies superficially on face, anterior to ear.
• Parotid duct passes into the oral vestibule cavity
• Produces serous secretions

Question 25

Where is the submandibular gland and what sort of saliva does it produce?

Answer 25

• Lies along body of mandible
• Submandiular duct passes into the oral cavity proper (under tongue)
• Produces both mixture of serous & mucous secretions

Question 26

Where is the sublingual gland and what sort of saliva does it produce?

Answer 26

• Smallest glands lying on the floor of the mouth (under tongue)
• mucous secretion

Question 27

What is the sensory innervation of the oral cavity?

Answer 27

• Trigeminal nerve
  
  • V2 –> hard palate & upper lip
  • V3 –> anterior tongue (general sense) & lower lip
• Facial nerve
  
  • VII –> Taste on anterior tongue (Chorda
    tympani)
• Glossopharyngeal nerve
  
  • IX –> Posterior tongue and pillars of fauces (taste & general)
• Vagus nerve
  
  • X –> Oropharynx (general & taste)