Oral Cavity Flashcards
What is the function of the oral cavity
What are the 2 sections that make up the oral cavity
Entry point to the GI tract => oropharynx
-mouth => food, drink tasted, mixed with saliva, masticated, swallowed
Vestubule => space between teeth, mucosal inner lining of cheeks, lips
Oral cavity proper => space within dental arches, filled by tongue
What are the boundaries of the oral cavity
- roof
- anterior
- floor, posterior wall
Roof => maxilla and palatine (hard palate)
Anterior => maxilla, mandible dental arches
Floor, posterior => soft tissues
What structures make up the roof of the mouth
-bones and muscles
Maxilla => separates oral and nasal cavity
-anterior 2/3 of roof
Palatine => separates oral and nasal cavity
- posterior 1/3 of roof
- soft palate attachment
Soft palate muscles
- levator palatini => elevates soft palate to prevent food entering nasopharynx
- X
- palatopharyngeus => helps form the palatopharyngeal arch
- X
- palatoglossus => helps form the glossopalatine arch, pulls soft palate towards tongue
- X
- tensor veli palatini => tenses soft palate
- medial pterygoid nerve (V3)
What structures make up the floor of the mouth
-mucus membranes and muscles
Depress the mandible and lift hyoid
Anterior belly of digastric =>digastric fossa of mandible to hyoid
-inferior alveolar nerve (V3)
Mylohyoid => paired muscle from mandible to hyoid
-inferior alveolar nerve (V3)
Geniohyoid => inferior mental spine to hyoid
-C1
What are the functions of the lips
-describe the arterial and nerve supply
Lips => grasping food, suckling, speech, act as a sphincter
-musculofibrous folds containing orbicularis oris, vessels, nerves
- Upper and lower labial arteries <= facial
- Upper labial nerves <= infraorbital (V2)
- Lower labial nerves <= mental (V3)
What are the functions of the cheeks
-describe the arterial and nerve supply
Cheeks => suckling, facial expression, speech
- continuous with lips, movable walls of oral cavity
- push cheek towards food to prevent food entering vestibule
- enclose buccinators, fat
- Buccal arteries <= maxillary branch
- Buccal nerves <= mandibular branch (VII)
What is the name of the transitional zone between the mucous membrane and skin on the lips
-what is the significance of this region
Vermillion border
-no glands, must be licked to keep it moist
Describe the nerve supply to the mucosa of the oral cavity
- roof
- lateral
- floor
Roof => maxillary nerve
Lateral wall, floor => lingual branch (V3)
Describe your teeth
- function
- structure
- innervation
32 permanent teeth
- erupt between 6-18
- incise, masticate, assist with speech
Crown => dentine and enamel
Neck => dentine
Root => dentine and cement
-alveolar branches of maxillary, mandibular nerve
Describe the tongue
- function
- structure
- innervation
Mobile muscular organ covered by mucus membrane
ALL INNERVATED BY XII EXCEPT PALATOGLOSSUS
Intrinsic => shape of tongue (XII)
- superior longitudinal
- inferior longitudinal
- transverse
- vertical
Extrinsic => change position
-genioglossus => mandibular symphysis, hyoid, entire length of tongue
- hyoglossus => hyoid, side of tongue
- styloglossus => styloid process, side of tongue
- palatoglossus => palatine aponeurosis, tongue (PHARYNGEAL PLEXUS)
Describe the sensory and taste innervation of the tongue
- anterior 2/3
- posterior 1/3
Anterior 2/3
- general sensation => lingual (V3)
- taste => chorda tympani (VII)
Posterior 1/3 and vallate pappilae
-general sensation & taste => lingual branch (IX)
Very posterior
-general sensation & taste => X
Describe the
- arterial supply
- venous supply
- lymphatic drainage of the tongue
Arterial
-ECA => lingual artery (deep to hypoglossus muscle)
Venous
- dorsum and sides => posterior lingual veins => lingual vein => IJV
- rest => deep lingual, sublingual => facial vein
Lymphatic drainage done in regions => deep cervical nodes => jugular, subclavian veins
What is the function of the salivary glands
- where are they
- what do they secrete
Keep mouth moist
Parotid => on masseter, duct pierces buccinator => opens via 2nd molar tooth, serous (IX)
Sublingual => 16-20 short ducts into floor, mucus (VII)
Submandibular => superior to digastric, each gland separated superoinferiorly by mylohyoid => floor of mouth, mixed (VII)
Minor glands maintain oral hygeine in the background
