S

salivary glands Structures within the MOUTHthat
produce saliva, a watery fluid that mixes with
food during chewing and maintains the mouth as
a moist environment. The major salivary glands
are primarily along the floor of the mouth (the
sublingual and submandibular glands) and at
the back of the mouth just below the EAR
(parotid glands). These glands produce a steady
supply of saliva that trickles into the mouth to
moisturize mucous membranes. Stimuli related to
eating, such as the smell or appearance of food,
activate an increased flow of saliva to meet the
needs of mastication (chewing). Enzymes in saliva
begin to break down foods to prepare them for
digestion.
The facial and glossopharyngeal nerves, the
seventh and ninth CRANIAL NERVES respectively,
regulate the functions of the salivary glands. The
glossopharyngeal NERVE also handles nerve
impulses for the sense of taste. Small mineral cal-
culi, or stones, can block the salivary ducts that
drain saliva from the salivary glands, causing PAIN
and swelling (SIALOLITHIASIS). Excessive saliva (SIAL-
ORRHEA), or drooling, can a symptom of various
neurologic conditions, including CEREBRAL PALSY
and PARKINSON’S DISEASE, and often accompanies
SWALLOWING DISORDERS. Saliva production tem-
porarily increases in young children who are
teething, likely an attempt by the body to soothe
the discomfort of the new TEETHerupting through
the surface of the gums. The parotid glands swell
with the MUMPS.
For further discussion of the salivary glands
within the context of otolaryngologic structure
and function please see the overview section “The
Ear, Nose, Throat, and Mouth.”
See also SIALADENITIS.

septal deviation A shift from midline in the

nasal septum (wall of tissue that separates the air

pathways of the NOSE). Septal deviation can cause

various health conditions such as chronic SINUSITIS

(INFECTION), EPISTAXIS (nosebleed), and obstructed

BREATHING. It can occur as a natural defect or result

from trauma such as a blow to the nose. The treat-

ment of choice is surgical correction (septoplasty)

to restore the septum to midline. Septal deviation

often accompanies structural anomalies of the

nose that cause people to seek RHINOPLASTY(surgi-

cal reconstruction of the nose).

See also SEPTAL PERFORATION; SURGERY BENEFIT AND

RISK ASSESSMENT.

septal perforation An abnormal opening in the

nasal septum (wall of tissue within the NOSEthat

divides the nostrils), that occurs as the result of

chronic irritation, trauma, or cancer. Septal perfo-

ration may develop with long-term use of nasal

oxygen, long-term use of corticosteroid nasal

sprays (such as to treat ALLERGIC RHINITIS), inhala-

tion of illicit drugs such as COCAINEor aerosols and

glues, foreign objects in the nose, chronic digital

trauma (picking the nose), or long-term exposure

to chromates such as chromic acid and chromium

(used in electroplating and other industrial appli-

cations). Septal perforation sometimes occurs as a

consequence of RHINOPLASTY, particularly when

there have been several operations.

Symptoms of septal perforation may include a

whistling sound when BREATHING, nasal discharge,

and bleeding (EPISTAXIS). The preferred treatment

for most septal perforations is surgical repair (sep-

toplasty), though it is sometimes necessary to first

remedy the underlying cause. The doctor may

place a nasal septal prosthesis, commonly called a

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