Burning Mouth Syndrome is characterized by a burning pain
in the tongue, lips, or other oral sites, usually without any known
source. About 1.3 million American adults suffer from burning mouth
syndrome, most being pre-menopausal women. Symptoms that are also
experienced by affected patients are dry
mouth and taste alterations. Most patients will awaken without
pain or symptoms, but note increasing sensations throughout their
day. In addition to the symptoms experienced, chronic anxiety or
depression, nutritional deficiencies, type 2 diabetes, and changes
in salivary function are other conditions that have been reported.
However, according to the February 2002 article written by Grushka,
Epstein, and Gorsky of the American Academy of Family Physicians,
these conditions have not been consistently linked to the syndrome
and their treatment has had little impact on burning mouth symptoms.
Studies have pointed to the dysfunction of several cranial nerves
associated with taste sensation as a possible cause of burning mouth
syndrome. Some effective treatments for patients include low dosages
of benzodiazepines, tricyclic antidepressants, or anticonvulsants,
and topical capsaicin (American Family Physician 2002;65:615).
Etiologic Factors of BSM:
Psychologic Dysfunction: Anxiety and depression have been
consistently reported in patients with burning mouth syndrome. Personality
and mood changes; however, is common in patients suffering from
chronic pain which suggests that the conditions maybe a result of
pain rather than the burning mouth syndrome. The use of tricyclic
antidepressants and some benzodiazepines as pain coping treatments
have proven effective due to their analgesic and anticonvulsant
properties (American Family Physician 2002;65:616-617).
Hormonal Changes: Hormonal changes are considered to be
a prominent source of burning mouth syndrome, even though significant
evidence of the effectiveness of hormone replacement therapy in
women with the disorder has yet to be founded (American Family Physician
2002;65:617). However, it is known that changes in hormone levels
can affect the composition of one’s saliva (Mayo Foundation for
Medical Education and Research, 2006).
Dry Mouth: Dry mouth (Xerostomia)
has often been suggested as an etiologic factor of burning mouth
syndrome due to its high occurrences in suffering patients. Although
studies have shown alterations in salivary components, salivary
flow rate tests have shown no decrease in neither stimulated nor
unstimulated salivary flow (American Family Physician 2002;65:617).
Dry mouth can also be related to the
use of certain medications, including tricyclic antidepressants,
central nervous system depressants, lithium, diuretics, and medications
used to treat high blood pressure. The condition can also occur
with aging or Sjogren’s syndrome,
and autoimmune disease that causes both
dry mouth and dry eyes (Mayo Foundation for Medical Education
and Research, 2006).
Taste Function: Although there is an increased prevalence
of so-called “supertasters” (persons with enhanced abilities to
detect taste) among patients with burning mouth syndrome, the role
of taste is not straightforward. Supertasters are more likely to
be affected by the burning sensations because of their higher density
of taste buds, each of which are encased by pain neurons of the
trigeminal nerve. (American Family Physician 2002;65:617) According
to Grushka, Epstein, and Gorsky of the American Academy of Family
Physicians, it has been suggested that damage to taste may also
be associated with loss of central inhibition of trigeminal-nerve
afferent pain fibers, which can lead to oral burning symptoms (American
Family Physician 2002;65:618).
Other Possible Causes: Nutritional deficiencies-lack of
nutrients such as iron, zinc, folate (vitamin B-9), thiamin (vitamin
B-1), riboflavin (vitamin B-2), pyridoxine (vitamin B-6) and cobalamin
(vitamin B-12), may affect one’s oral tissue and cause burning mouth
syndrome (Mayo Foundation for Medical Education and Research, 2006).
Endocrine disorders: Oral tissues often react to high
blood sugar levels that occur with conditions such as diabetes and
under active thyroid (hypothyroidism). Angiotensin-converting enzyme
(ACE) inhibitors which are used to treat high blood pressure can
also cause the burning sensation (Mayo Foundation for Medical Education
and Research, 2006).
Allergies: The burning sensation may be a result of an
allergic reaction to foods, food flavorings, and other food additives
such as dyes and fragrances (Mayo Foundation for Medical Education
and Research, 2006).
Oral habits: Oral irritation can be a result of unconscious
activities such as tongue thrusting or
teeth grinding (bruxism) (Mayo Foundation for Medical Education
and Research, 2006).