Oral Cavity and Tongue Flashcards
Oral region
* Includes: (5)
o Oral cavity
o Teeth and gingivae
o Tongue
o Palate
o Region of the palatine tonsils
Oral region:
Functions: (4)
o Formation of food bolus by mastication and
lingual manipulation
o Voluntary deglutition
o Manipulation of sound from the larynx (sound)
o Opening of the respiratory system
Divisions of the oral cavity: (2)
- Oral vestibule
- Oral cavity proper
What are the features of the Oral vestibule? (3)
- Slit-like space between the teeth & gingivae, and the lips & cheeks
- Communicates with the exterior through the oral fissure
- Size of the oral fissure is controlled by the peri-oral muscles
Peri-oral muscles: (4)
o Orbicularis oris
o Buccinator
o Risorius
o Depressors and elevators of the lips (dilators of the oral fissure)
What is the Oral cavity proper?
- The space between the upper and lower dental arches/arcades
- When the mouth is closed and at rest, the tongue fully occupies the cavity
What are the boundaries of the oral cavity proper? (4)
o Lateral and anterior- dental arches
o Superior (roof)- hard and soft palate
o Inferior (floor)- mylohyoid m., geniohyoid m. and tongue
o Posterior- oropharyngeal isthmus and oropharynx
What are the lips?
Mobile, musculofibrous folds surrounding the mouth lined externally by skin and internally by mucosa.
Lips
Extent: (2)
o Laterally and superiorly- nasolabial sulci and nares
o Inferiorly- mentolabial sulcus
What do the lips contain? (3)
o Orbicularis oris
o Superior and inferior labial muscles
o Superior and inferior labial nerves and vessels
What is the function of the lips?
o Valve of the oral fissure
What is the lymph drainage of the lips? (2)
o Upper lip and lateral lower lip drains into submandibular nodes
o Medial part of lower lip drains into submental nodes
What is the blood supply of the lips?
o Superior and inferior labial arteries from facial artery
What is the innervation of the lips? (2)
o Upper lip- superior labial br. of infraorbital br. of maxillary nerve (CN V2)
o Lower lip- inferior labial br. of mental br. of inferior alveolar n. from mandibular nerve (CN V3)
What are the cheeks? (2)
- Movable walls of the oral cavity that are continuous with the lips
- Functions in keeping food between teeth when chewing
Extent- the buccal region: (4)
Anterior-
Superior-
Posterior-
Inferior-
o Anteriorly- oral and mental regions
o Superiorly- zygomatic region
o Posteriorly- parotid region
o Inferiorly- inferior border of the mandible
What is the principle muscle of the cheek?
Principle muscle of the cheek is the buccinator
o Superficial to buccinator is the buccal ____-____
o Deep to buccinator are buccal _____
fat-pad
glands
What is the blood supply to the cheeks?
o Buccal branches of 2nd part of maxillary artery
What is the innervation to the cheeks? (2)
o Sensory- buccal branches of mandibular nerve (CN V3)
o Motor (to buccinator)- buccal branch of facial nerve (CN VII)
What is the Gingivae?
- Composed of fibrous tissue covered with mucous membrane
What is the Gingiva proper (attached gingiva)? (2)
- Firmly attached to the alveolar part of the mandible,
alveolar process of maxilla and necks of teeth - Pink, stippled and keratinized
What is the Alveolar mucosa (unattached gingiva)? (2)
- Continuation of the mucous membrane of the cheeks, lips and floor of the mouth
- Shiny red and nonkeratinizing
What is the innervation of the Gingivae? (2)
o anterior superior alveolar, middle superior alveolar and posterior superior alveolar br. from maxillary nerve
o buccal and mental br. of mandibular nerve
What are the features of the teeth? (3)
- Housed in alveolar bone
- 32 in adults, 20 in children
- Structure is dependent on position and function
o Incisors-
o Canines-
o Premolars-
o Molars-
o Incisors- chisel-shaped for cutting
o Canines- longest with single pointed cusp to grasp
o Premolars- 2 pointed cusps to grind
o Molars- 3 to 5 cusps to grind
Vasculature of the teeth: (2)
o superior and inferior alveolar aa. from the maxillary a.
o Alveolar vv. and pterygoid venous plexus to maxillary v.
Upper arcade- maxillary nerve:
Anterior superior alveolar
Teeth innervated:
Incisors and canines