Oral and Esophageal Physiology

Question 1

Importance of bicarb in saliva

Answer 1

neutralizes lactate made by oral flora bacteria

protects tooth enamel

Question 2

Secretions of:

parotid

submandibular

sublingual

Answer 2

parotid: serous (25% of total)
submandibular: mixed (70%)
sublingual: mucus (5%)

Question 3

Parasympathetic salivary control

Answer 3

facial and glossopharyngeal n.

glossopharyngeal above palate

facial below palate

increase watery secretions

VIP and ACh

Question 4

Sympathetic salivary control

Answer 4

cervical sympathetic chain

increase mucus secretions at low levels

stop secretions at high levels

NE on a1 and b1 receptors

Question 5

Pregnancy/menapause and dry mouth

Answer 5

pregnancy: hypersalivation
menapause: hyposalivation

Question 6

Xerostomia

Answer 6

subjective oral dryness

Question 7

Dental complications of dry mouth

Answer 7

opportunistic infections

tooth decay (pH)

dysphagia

Question 8

Salivary amylase function

Answer 8

cleave alpha-1,4 glycocytic linkages until reaches stomach acid

Question 9

Tongue motor

Answer 9

CNXII hypoglossal

Question 10

Tongue sensory

Answer 10

CNIX glossopharyngeal

CNVII facial

Question 11

Dysguesia

Answer 11

inability to taste

infection, aging, nutritional deficiencies

Question 12

UES and LES close between swallows to prevent

Answer 12

air entering stomach

acid entering esophagus

(thorax is a negative pressure!)

Question 13

Steps in swallowing

Answer 13

tongue contacts hard palate

→ push bolus back

bolus passes over epiglotis

→ breathing inhibited

peristalis + gravity

→ moves bolus toward stomach

Question 14

Coordination of swallowing with respiraration

Answer 14

medullary swallowing centers

CNIX and X

Question 15

Primary peristalsis in esophagus

Answer 15

parasympathetic nerves and enteric neurons

circular and longitudinal muscles

food may get stuck ⇒ secondary peristalsis

Question 16

Secondary peristalsis

Answer 16

enteric neurons

creat strong peristaltic wave if something gets stuck

or acid in esophagus

Question 17

Retrograde esophageal movements

Answer 17

relaxation of UES and LES, no reverse peristalsis

Question 18

Diffuse esophageal spasms

Answer 18

uncoordinated contractions ⇒ regurgitation

Question 19

Nutcracker esophagus

Answer 19

painful contractions

Question 20

Achalasia primary cause

Answer 20

loss of myenteric (Auerbach) plexus

inability to relax LES

Question 21

Appearnach of achalasia on barium swallow

Answer 21

bird’s beak

Question 22

Dysphagia in achalasia

Answer 22

progressive

solids and liquids

not just solids like obstruction

Question 23

Severe GERD

Answer 23

epithelial erosion, Barrett’s esophagus

Question 24

Innervation of LES

Answer 24

enteric plexus neurons