Unusual Headache Syndromes
Although known for more than a century, the BMS was not formally categorized as a distinct disorder until 2004, when the International Headache Society (IHS) included it in the ICHD-II as a disease with the following criteria:
"An intraoral burning sensation for which no medical or dental cause can be found.
Diagnostic criteria:
A few modifications were introduced recently with the new ICHD-3 Beta:
"Description:
An intraoral burning or dysaesthetic sensation, recurring daily for more than 2 hours/day over more than 3 months, without clinically evident causative lesions.
Diagnostic criteria:
This syndrome was previously known as glossopyrosis, oral dysesthesia, sore tongue, stomatodynia, stomatopyrosis, or scalded mouth syndrome.
BMS is a relatively frequent intraoral pain disorder with an often chronic and disabling course. Lipton et al stated that 0.7% of the 45,000 American households interviewed reported having BMS. In postmenopausal women, the prevalence may reach 12–18%. The intraoral discomfort (reported as burning, tender, tingling, hot, scalding, and numb sensation) may involve different intraoral sites, and the anterior part and tip of tongue are the sites most commonly affected.
Previously, Scala et al developed criteria for the diagnosis of BMS, including: daily and deep burning sensation of the oral mucosa (bilateral); burning sensation for at least 4–6 months; constant intensity, or increasing intensity during the day; no worsening on eating or drinking, although the symptoms may improve; no interference with sleep; dysgeusia and/or xerostomia; sensory or chemosensory alterations; and mood changes or psychopathological alterations.
The BMS has a multifactorial etiology with enigmatic pathophysiology. A few studies involving patients with BMS reported possible damage in both peripheral and central neuronal systems, such as: (1) a change in thermal and nociception thresholds, suggesting a neuropathic origin of the syndrome; (2) lower density of epithelial and subpapillary nerve fibers, consistent with axonal degeneration (trigeminal small-fiber sensory neuropathy or axonopathy; (3) a central deficiency in dopaminergic neurons; (4) high levels of neural growth factors in the saliva of BMS individuals; (5) changes in TRPV1 ion channels and P2X3 receptors; (6) a decrease in brain activation to heat stimuli observed by fMRI; and (7) increased excitability or inhibition of the trigeminal system, as patients with BMS have altered blink reflexes.
BMS can be divided into primary (essential or idiopathic) or secondary forms. Thus, primary BMS is a diagnosis of exclusion and all possible causes of secondary BMS must be ruled out. Some authors prefer to refer to secondary BMS as "burning mouth sensations" because, rather than being an idiopathic nosological entity, it represents the symptomatology of a myriad of causes. In more than one third of the patients with BMS, one or more possible causes can be found. Drug therapy is a major cause of the syndrome. Antihypertensive agents, anticoagulants, antidepressants, antipsychotics, antiretrovirals, benzodiazepines, hormone replacement therapy (estradiol, dydrogesterone), chemotherapy, and metoclopramide, have all been reported to cause BMS-like symptoms. Usually, the symptoms will appear within a few weeks of the onset of pharmacological treatment and the relief of symptoms occurs by suspending or decreasing the dose of the offending medication.
Subjective xerostomia (ie, dry mouth sensation without hyposalivation) is a frequent complaint in patients with idiopathic BMS. Subjects with secondary BMS may present true xerostomia (complaining of having a "cotton mouth"), due to a lack of saliva production, as in Sjögren's syndrome.
Some patients report a relief in the BMS pain symptoms after eating, suggesting that the stimulation of the gustatory system may decrease pain sensation.
In Table 2, some of the risk factors or conditions related to BMS are listed and, when present, a specific management is suggested to attenuate or treat the disease. Chronic medical conditions (gastrointestinal and urogenital diseases, diabetes mellitus), psychiatric illnesses (depression, anxiety, hypochondria, cancer phobia, personality disorders, panic attacks), globus pharynges, Sjögren's syndrome, lupus erythematous, oral infections (particularly candidiasis, enterobacter, and klebsiella), drug use, dental treatment, hypovitaminosis (B1, B2, B6, B12, folic acid), mineral deficiencies (iron, zinc), dietary antigens, smoking, hormonal changes (eg, hypothyroidism, postmenopausal period), and Parkinson's disease are some of the conditions that have been associated with BMS.
There is little research support providing a clear direction for the treatment of subjects with BMS. Although BMS does not represent a risk of death to the patients, it causes a very strong negative impact on their quality of life. Although psychiatric disorders cannot be considered as a primary cause, in more than 50% of the patients BMS is associated with depression, anxiety, or personality disorders, in the latter mostly from cluster A, including paranoid and schizoid types.
BMS is an extremely difficult disorder to treat, as a result of which its management is very challenging. Often patients with BMS have a long history of unsuccessful dental and medical consultations. Different classes of medication have been used with partial success. Due to the various mechanisms implicated in the etiology of BMS, a multidisciplinary approach is required. Medications commonly prescribed include benzodiazepines, antidepressants, antipsychotic, anticonvulsants, antioxidant, pramipexol, and alpha lipoic acid. Topical clonazepam and cognitive therapy seem to work in some subjects.
BMS is a chronic illness, and a spontaneous partial recovery can be observed in part of the patients only years after the onset of the disease. In one third of the patients, the syndrome may be permanent. When recovery does occur, it is usually preceded by a change from continuous to intermittent symptomatology. In a series of 53 patients with BMS, a moderate improvement and spontaneous remission was reported by only 30% and 3% of the individuals, respectively, within 5 years of onset.
Burning Mouth Syndrome
Although known for more than a century, the BMS was not formally categorized as a distinct disorder until 2004, when the International Headache Society (IHS) included it in the ICHD-II as a disease with the following criteria:
"An intraoral burning sensation for which no medical or dental cause can be found.
Diagnostic criteria:
Pain in the mouth present daily and persisting for most of the day;
Oral mucosa is of normal appearance;
Local and systemic diseases have been excluded. Comment: Pain may be confined to the tongue (glossodynia). Subjective dryness of the mouth, paresthesia and altered taste may be associated symptoms."
A few modifications were introduced recently with the new ICHD-3 Beta:
"Description:
An intraoral burning or dysaesthetic sensation, recurring daily for more than 2 hours/day over more than 3 months, without clinically evident causative lesions.
Diagnostic criteria:
Oral pain fulfilling criteria B and C;
Recurring daily for >2 hours/day for >3 months;
Pain has both of the following characteristics: (1) burning quality; (2) felt superficially in the oral mucosa.
Oral mucosa is of normal appearance and clinical examination including sensory testing is normal;
Not better accounted for by another ICHD-3 diagnosis."
This syndrome was previously known as glossopyrosis, oral dysesthesia, sore tongue, stomatodynia, stomatopyrosis, or scalded mouth syndrome.
BMS is a relatively frequent intraoral pain disorder with an often chronic and disabling course. Lipton et al stated that 0.7% of the 45,000 American households interviewed reported having BMS. In postmenopausal women, the prevalence may reach 12–18%. The intraoral discomfort (reported as burning, tender, tingling, hot, scalding, and numb sensation) may involve different intraoral sites, and the anterior part and tip of tongue are the sites most commonly affected.
Previously, Scala et al developed criteria for the diagnosis of BMS, including: daily and deep burning sensation of the oral mucosa (bilateral); burning sensation for at least 4–6 months; constant intensity, or increasing intensity during the day; no worsening on eating or drinking, although the symptoms may improve; no interference with sleep; dysgeusia and/or xerostomia; sensory or chemosensory alterations; and mood changes or psychopathological alterations.
The BMS has a multifactorial etiology with enigmatic pathophysiology. A few studies involving patients with BMS reported possible damage in both peripheral and central neuronal systems, such as: (1) a change in thermal and nociception thresholds, suggesting a neuropathic origin of the syndrome; (2) lower density of epithelial and subpapillary nerve fibers, consistent with axonal degeneration (trigeminal small-fiber sensory neuropathy or axonopathy; (3) a central deficiency in dopaminergic neurons; (4) high levels of neural growth factors in the saliva of BMS individuals; (5) changes in TRPV1 ion channels and P2X3 receptors; (6) a decrease in brain activation to heat stimuli observed by fMRI; and (7) increased excitability or inhibition of the trigeminal system, as patients with BMS have altered blink reflexes.
BMS can be divided into primary (essential or idiopathic) or secondary forms. Thus, primary BMS is a diagnosis of exclusion and all possible causes of secondary BMS must be ruled out. Some authors prefer to refer to secondary BMS as "burning mouth sensations" because, rather than being an idiopathic nosological entity, it represents the symptomatology of a myriad of causes. In more than one third of the patients with BMS, one or more possible causes can be found. Drug therapy is a major cause of the syndrome. Antihypertensive agents, anticoagulants, antidepressants, antipsychotics, antiretrovirals, benzodiazepines, hormone replacement therapy (estradiol, dydrogesterone), chemotherapy, and metoclopramide, have all been reported to cause BMS-like symptoms. Usually, the symptoms will appear within a few weeks of the onset of pharmacological treatment and the relief of symptoms occurs by suspending or decreasing the dose of the offending medication.
Subjective xerostomia (ie, dry mouth sensation without hyposalivation) is a frequent complaint in patients with idiopathic BMS. Subjects with secondary BMS may present true xerostomia (complaining of having a "cotton mouth"), due to a lack of saliva production, as in Sjögren's syndrome.
Some patients report a relief in the BMS pain symptoms after eating, suggesting that the stimulation of the gustatory system may decrease pain sensation.
In Table 2, some of the risk factors or conditions related to BMS are listed and, when present, a specific management is suggested to attenuate or treat the disease. Chronic medical conditions (gastrointestinal and urogenital diseases, diabetes mellitus), psychiatric illnesses (depression, anxiety, hypochondria, cancer phobia, personality disorders, panic attacks), globus pharynges, Sjögren's syndrome, lupus erythematous, oral infections (particularly candidiasis, enterobacter, and klebsiella), drug use, dental treatment, hypovitaminosis (B1, B2, B6, B12, folic acid), mineral deficiencies (iron, zinc), dietary antigens, smoking, hormonal changes (eg, hypothyroidism, postmenopausal period), and Parkinson's disease are some of the conditions that have been associated with BMS.
There is little research support providing a clear direction for the treatment of subjects with BMS. Although BMS does not represent a risk of death to the patients, it causes a very strong negative impact on their quality of life. Although psychiatric disorders cannot be considered as a primary cause, in more than 50% of the patients BMS is associated with depression, anxiety, or personality disorders, in the latter mostly from cluster A, including paranoid and schizoid types.
BMS is an extremely difficult disorder to treat, as a result of which its management is very challenging. Often patients with BMS have a long history of unsuccessful dental and medical consultations. Different classes of medication have been used with partial success. Due to the various mechanisms implicated in the etiology of BMS, a multidisciplinary approach is required. Medications commonly prescribed include benzodiazepines, antidepressants, antipsychotic, anticonvulsants, antioxidant, pramipexol, and alpha lipoic acid. Topical clonazepam and cognitive therapy seem to work in some subjects.
BMS is a chronic illness, and a spontaneous partial recovery can be observed in part of the patients only years after the onset of the disease. In one third of the patients, the syndrome may be permanent. When recovery does occur, it is usually preceded by a change from continuous to intermittent symptomatology. In a series of 53 patients with BMS, a moderate improvement and spontaneous remission was reported by only 30% and 3% of the individuals, respectively, within 5 years of onset.