Oral Mucosa

Question 1

Function of oral mucosa

Answer 1

Protect against shearing and compressive forces

Barrier to bacteria and toxins

Immunological defence via langerhans cells in lamina propria

Salivary ducts provide lubrication and buffering

Rich innervation for sensory perception

BRISP

Question 2

Describe masticatory mucosa

Answer 2

Found at attached gingiva, dorsal surface of tongue, hard palate

Rubbery texture, found at areas of high compression and friction

Question 3

Describe lining mucosa

Answer 3

Ventral tongue surface, soft palate, floor of mouth, alveolar mucosa

Soft texture, pliable. Mobile and distensible. Redder due to higher concentration of capillaries, thinner epithelium, less keratinisation.

Question 4

What is specialised mucosa

Answer 4

Found on dorsal tongue surface, associated with papilla

Question 5

Describe the histology of masticatory mucosa BPGK

Answer 5

Interface between epithelium and lamina propria is highly interdigitated with numerous rete pegs, which are epithelial extensions that project into connective tissue. This provides firm support

Basal layer: single cell layer, cuboidal cells, stem cells. Demarcated from lamina propria by basal lamina

Prickle cell layer: keratinocytes joined to each other by desmosomes

Granular layer: larger and flatter keratinocytes. Organelles reduced or lost. Keratohyaline release lipid rich contents into intercellular space

Keratinised layer: shed through desquamation as desmosomes weaken and disappear, resulting in constant turnover of epithelial cells. Mechanical protective function. Disulphide bond provide mechanical and chemical resistance.

Question 6

Compare lining and masticatory mucosa

Answer 6

Lining mucosa has fewer and less pronounced rete peg. Lining mucosa lamina propria has elastic fibres, making it more pliable. Lining mucosa not keratinised, lack keratinohyaline granules

Question 7

What is the function of lamina propria

Answer 7

Mechanical support for epithelium. Provide nutrition. Sensory function via nerves. Defence via saliva and immunocompetent cells

Question 8

What is the arterial blood supply to the upper lip

Answer 8

Superior labial artery

Question 9

Arterial blood supply to upper gingiva

Answer 9

Anterior: anterior superior alveolar artery

Lingual: major palatine artery

Buccal: buccal artery

Posterior: posterior superior alveolar artery

Question 10

Arterial blood supply to hard palate

Answer 10

Major palatine artery, nasopalatine artery

Question 11

Arterial blood supply of cheek

Answer 11

Buccal artery, infraorbital artery, posterior alveolar artery

Question 12

Blood supply of lower gingiva

Answer 12

Anterior buccal: mental artery

Anterior lingual: incisive artery and sublingual artery

Posterior lingual: inferior alveolar artery

Posterior buccal: inferior alveolar artery

Question 13

Blood supply to the tongue

Answer 13

Anterior 2/3: deep lingual artery

Posterior 1/3: dorsal lingual artery

Question 14

Innervation to upper lip and vestibule

Answer 14

Infraorbital branch of maxillary nerve

Question 15

Innervation to upper gingiva

Answer 15

Superior alveolar branches of maxillary nerve

Question 16

Innervation to soft palate

Answer 16

Lesser palatine branch of maxillary nerve, tonsillar branch of glossopharyngeal nerve

Question 17

Innervation to lower lip and vestibule

Answer 17

Mental branch of inferior alveolar nerve and buccal nerve (branch of CNV3)