Burning mouth syndrome: a possible etiologic role for local contact hypersensitivity

Burning Mouth Syndrome and Contact Dermatitis

: Burning mouth syndrome (BMS) is a condition that remains a diagnostic challenge and is frequently difficult to treat. Rather than being a singular entity, more recent research has suggested that the diagnosis of BMS encompasses a family of syndromes. Of this family, type 3 has been identified as being related to contact dermatitis. Although this subtype has been most commonly associated with dental allergens, several food, cosmetic, and pharmaceutical products have also been identified as allergens related to the onset of BMS. Failure to identify these allergens prevents timely diagnosis and initiation of treatment for patients with BMS related to contact dermatitis. This article identifies the allergens most relevant to this type 3 and describes the commercially available allergy panels needed to ensure that all relevant allergens are included during patch testing. This study also describes approaches to diagnosis of BMS and discusses approaches to treatment based on subtypes of the condition.

An updated review on pathophysiology and management of burning mouth syndrome with endocrinological, psychological and neuropathic perspectives

Burning mouth syndrome (BMS) is a chronic oro-facial pain disorder of unknown cause. It is more common in peri- and post-menopausal women, and sex hormone dysregulation is believed to be an important causative factor. Psychosocial events often trigger or exacerbate symptoms, and persons with BMS appear to be predisposed towards anxiety and depression. Atrophy of small nerve fibres in the tongue epithelium has been reported, and potential neuropathic mechanisms for BMS are now widely investigated. Historically, BMS was thought to comprise endocrinological, psychosocial and neuropathic components. Neuroprotective steroids and glial cell line-derived neurotrophic factor family ligands may have pivotal roles in the peripheral mechanisms associated with atrophy of small nerve fibres. Denervation of chorda tympani nerve fibres that innervate fungiform buds leads to alternative trigeminal innervation, which results in dysgeusia and burning pain when eating hot foods. With regard to the central mechanism of BMS, depletion of neuroprotective steroids alters the brain network-related mood and pain modulation. Peripheral mechanistic studies support the use of topical clonazepam and capsaicin for the management of BMS, and some evidence supports the use of cognitive behavioural therapy. Hormone replacement therapy may address the causes of BMS, although adverse effects prevent its use as a first-line treatment. Selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs) may have important benefits, and well-designed controlled studies are expected. Other treatment options to be investigated include brain stimulation and TSPO (translocator protein 18 kDa) ligands.

Sublingual administration of 2-hydroxyethyl methacrylate enhances antibody responses to co-administered ovalbumin and Streptococcus mutans

OBJECTIVE

The oral mucosa of patients undergoing dental procedures is often exposed to residual monomers leaking from incompletely cured acrylic resins. We investigated whether 2-hydroxyethyl methacrylate (HEMA) monomers applied to the sublingual mucosa in mice modulate the antibody responses towards co-administered ovalbumin (OVA) or live oral bacteria.

MATERIAL AND METHODS

OVA, live mouse oral commensal Lactobacillus murinus or live human oral commensal Streptococcus mutans were administered sublingually with or without HEMA to BALB/c mice on four weekly occasions. One week after the last administration, the experiment was terminated and serum antibody levels were analyzed using ELISA.

RESULTS

Significantly increased IgG and IgE anti-OVA antibody activity was found in the sera from mice immunized with OVA together with HEMA, as compared to mice immunized with OVA alone. Likewise, S. mutans together with HEMA induced an IgG anti-S. mutans antibody response that was significantly higher than the antibody response detected after application of S. mutans alone. No IgG anti-L. murinus antibody response was detected in mice immunized with L. murinus together with HEMA, as compared to the background activity.

CONCLUSIONS

We report that HEMA monomers have adjuvant properties when sublingually administered in combination with OVA or S. mutans.

Clinically relevant patch test results in patients with burning mouth syndrome

BACKGROUND

Patients with a sore or burning mouth associated with clinically normal oral mucosa present a difficult diagnostic challenge.

OBJECTIVE

The objective of this study was to assess the value of patch testing in patients with burning mouth syndrome.

METHODS

We retrospectively reviewed the results of patch testing to an oral series in patients with burning mouth syndrome seen at Mayo Clinic, Rochester, Minnesota, between January 2000 and April 2006.

RESULTS

Of 195 consecutive patients with a burning or sore mouth, 75 had patch testing to an oral series, and 28 of these patients (37.3%) had allergic patch test reactions. The most common allergens were nickel sulfate hexahydrate 2.5%, balsam of Peru, and gold sodium thiosulfate 0.5%. On follow-up, 15 patients reported improvement, 4 removed or avoided the offending dental metal, and 6 avoided the dietary allergen. Thirteen patients did not improve; 6 avoided identified allergens, but without improvement; 1 removed dental metals without symptom change; and 5 avoided test-positive dietary allergens but without improvement. The remaining 7 nonresponders had nonrelevant patch test results or did not avoid allergens.

CONCLUSIONS

Patch testing can identify patients who may be allergic to dental metals or dietary additives and who may benefit from removal or avoidance of these.

Burning Mouth Syndrome

The aetiology of BMS remains an enigma, however novel evidence suggests a neuropathic basis, which may explain concomitant vulvodynia in some patients.The constant high level spontaneous chronic pain in BMS has significant functional and psychological repercussions for these patients.Cognitive behavioural therapy remains the sole evidence based management of this condition, whilst some patients respond to treatment with Tricyclic antidepressants, SSRIs or SNRIs, compliance with medication remains an issue due to pharma side effects.Increasing evidence suggests that there may be 3 subgroups that should be managed differently.

Cutaneous and systemic hypersensitivity reactions to metallic implants

Cutaneous reactions to metal implants, orthopedic or otherwise, are well documented in the literature. The first case of a dermatitis reaction over a stainless steel fracture plate was described in 1966. Most skin reactions are eczematous and allergic in nature, although urticarial, bullous, and vasculitic eruptions may occur. Also, more complex immune reactions may develop around the implants, resulting in pain, inflammation, and loosening. Nickel, cobalt, and chromium are the three most common metals that elicit both cutaneous and extracutaneous allergic reactions from chronic internal exposure. However, other metal ions as well as bone cement components can cause such hypersensitivity reactions. To complicate things, patients may also develop delayed-type hypersensitivity reactions to metals (ie, in-stent restenosis, prosthesis loosening, inflammation, pain, or allergic contact dermatitis) following the insertion of intravascular stents, dental implants, cardiac pacemakers, or implanted gynecologic devices. Despite repeated attempts by researchers and clinicians to further understand this difficult area of medicine, the association between metal sensitivity and cutaneous allergic reactions remains to be fully understood. This review provides an update of the current knowledge in this field and should be valuable to health care providers who manage patients with conditions related to this field.

Burning Mouth Syndrome: Will Better Understanding Yield Better Management?

"Burning mouth syndrome" (BMS) refers to a chronic orofacial pain disorder usually unaccompanied by mucosal lesions or other clinical signs of organic disease. BMS is typically characterized by a continuous, spontaneous, and often intense burning sensation as if the mouth or tongue were scalded or on fire. Burning mouth syndrome is a relatively common condition. The estimated prevalence of BMS reported in recent studies ranges between 0.7 and 4.6% of the general population. About 1.3 million American adults, mostly women in the postmenopausal period, are afflicted with BMS. The etiology of this disorder is poorly understood even though new evidence for a possible neuropathic pathogenesis of idiopathic BMS is emerging. Burning mouth syndrome may present as an idiopathic condition (primary BMS type) distinct from the symptom of oral burning that can potentially arise from various local or systemic abnormalities (secondary BMS type), including nutritional deficiencies, hormonal changes associated with menopause, local oral infections, denture-related lesions, xerostomia, hypersensitivity reactions, medications, and systemic diseases including diabetes mellitus. In more than a third of patients, multiple, concurrent causes of BMS may be identified. It is important to note that the diagnosis of BMS should be established only after all other possible causes have been ruled out. Professional delay in diagnosing, referring, and appropriately managing of BMS patients occurs frequently. Treatment should be tailored to each patient and it is recommended to practice the treatment in a multidisciplinary facility. This article discusses our current understanding of the etiology and pathogenesis of BMS. The authors have tried to emphasize new pharmacological approaches to manage this challenging disorder.

Identification of urinary metabolites of orally administered N,N-dimethyl-p-toluidine in male F344 rats

The metabolism of orally administered N,N-dimethyl-p-toluidine (DMPT) in male F344 rats was investigated. The rat urinary metabolite profile was determined by analytical reverse-phase high performance liquid chromatography (HPLC). Four radiolabeled peaks were observed, isolated, and purified by solid-phase extraction (SPE) and preparative HPLC methods. The 4 peaks were identified as p-(N-acetylhydroxyamino)hippuric acid (M1), DMPT N-oxide (M2), N-methyl-p-toluidine (M3), and parent DMPT. Metabolites M1 and M2 were identified by spectrometric and spectroscopic methods, including mass fragmentation pattern identification from both liquid chromatography/mass spectrometry and gas chromatography/mass spectrometry, and from chemical analysis of nuclear magnetic resonance spectra. Structural confirmation of metabolite M2 was accomplished by comparison with a synthetic standard. Peaks M3 and the peak suspected to be DMPT were identified by comparison of their HPLC retention times and mass fragmentation patterns with authentic standards of N-methyl-p-toluidine and DMPT, respectively. DMPT metabolism is similar to that reported for N,N-dimethylaniline.

Disposition of [14C]N,N-dimethyl-p-toluidine in F344 rats and B6C3F1 mice

N,N-Dimethyl-p-toluidine (DMPT) is used as a polymerization accelerator, in industrial glues, and as an intermediate in dye and pesticide synthesis. There is potential for human exposure to DMPT. The disposition of oral and intravenous (i.v.) doses of [14C]DMPT in F344 rats and B6C3F1 mice was investigated. A single i.v. (2.5 mg/kg) or oral (2.5, 25, or 250 mg/kg) dose of [14C]DMPT (1-25 microCi) was administered in an aqueous vehicle to male rats and mice. The 25-mg/kg oral dose was administered to females to investigate possible gender differences in disposition. However, no striking gender differences were observed. Since toxicity studies conducted elsewhere used a corn oil vehicle, the 250-mg/kg oral dose also was administered in corn oil to male rats; disposition was not dependent on vehicle. Excreta (through 24 h) and tissues collected at sacrifice were analyzed for total radioactivity. Dose-dependent differences in toxicity and disposition were observed. Toxicity at the 250-mg/kg oral dose to male mice was consistent with acute renal failure. At the same dose, male rats exhibited clinical signs of toxicity through 12 h but were clinically normal by 24 h. At lower oral doses, [14C]DMPT-derived radioactivity was well absorbed and rapidly excreted, primarily in urine.

Investigation of reactions to dental materials

Patients undergoing dental treatment can be exposed to a wide range of potential allergens, but adverse events seem infrequent. Patients with symptoms or signs of stomatitis, burning, tingling, cheilitis, oral lichenoid lesions, lip and facial swelling may relate their problems to dental treatment or to the use of dental products. Investigation for immediate type or delayed type hypersensitivity is indicated using patch testing, prick testing and blood tests for allergen-specific IgE. The main allergic reactions found in patients include contact allergy to metals, cosmetics, food additives, flavours and acrylates, and immediate type allergy to latex. Adverse reactions following the administration of local anaesthetics are seen in about 0.5% of cases, but immediate type allergy to these agents is rare. In dental staff, occupationally related problems are common and usually take the form of hand or facial dermatitis or respiratory disease. The most common allergic reactions in dental staff are immediate type allergy to latex, and contact allergy to rubber additives, fragrances, acrylates and formaldehyde. Occupational irritant problems causing hand dermatitis are probably more common in dental personnel than is dermatitis caused by contact allergy. Patch testing and tests for immediate type allergy are useful investigative methods in the investigation of patients who present with oral or facial symptoms possibly related to dental treatments and are also beneficial in dental personnel who present with hand or facial dermatitis or respiratory symptoms.

Gold trichloride and gold sodium thiosulfate as markers of contact allergy to gold

The usefulness of a trivalent gold salt, gold trichloride (GTC), was evaluated as a marker of contact allergy to gold. Patients patch test-positive or patch test-negative to gold sodium thiosulfate (GSTS), 13 subjects of each, were patch tested with dilution series of GTC and equimolar concentrations of GSTS. In order to avoid false-positive and false-negative test reactions, the salts were buffered and placed on polypropene chambers. Allergic reactions were registered in 9/13 gold-allergic patients with GSTS and in 2/13 with GTC. The sum of positive reactions was 18 with GSTS and 5 with GTC. Irritant reactions were none with GSTS and 2 with GTC in the gold-allergic patients. It is concluded that GTC can elicit positive patch test reactions in patients with gold allergy but to a lesser degree when compared with GSTS. Thus, GTC cannot be recommended in patch testing, and GSTS is still the test agent of choice.

Treatment of glossodynia with olanzapine

A 73-year-old white male with a 6-month history of glossodynia, unresponsive to clotrimazole troches, cevimeline, triamcinolone dental paste, paroxetine, and lorazepam presented to the dermatology clinic for consultation. Work-up revealed no oral abnormalities and no underlying systemic disorder. He denied symptoms consistent with a psychiatric disorder. A detailed free amnestic assessment by a board certified Geriatric Psychiatrist (John S. Kennedy, MD) found that the patient was oppressed by the pain. He did not meet the criteria for major depression nor did he have any anxiety disorder or delusions. Because of the presence of dysphoria and anticipatory anxiety secondary to glossodynia, the patient was started on olanzapine. Improvement of pain symptoms were noted within 3 days with full resolution of symptoms at 1- and 3-month follow-ups. Dysphoria and anticipatory anxiety remitted fully upon pain relief.

Update on burning mouth syndrome: overview and patient management

Burning Mouth Syndrome (BMS) is a chronic pain syndrome that mainly affects middle-aged/old women with hormonal changes or psychological disorders. This condition is probably of multifactorial origin, often idiopathic, and its etiopathogenesis remains largely enigmatic. The present paper discusses several aspects of BMS, updates current knowledge, and provides guidelines for patient management. There is no consensus on the diagnosis and classification of BMS. The etiopathogenesis seems to be complex and in a large number of patients probably involves interactions among local, systemic, and/or psychogenic factors. In the remaining cases, new interesting associations have recently emerged between BMS and either peripheral nerve damage or dopaminergic system disorders, emphasizing the neuropathic background in BMS. Based on these recent data, we have introduced the concepts of "primary" (idiopathic) and "secondary" (resulting from identified precipitating factors) BMS, since this allows for a more systematic approach to patient management. The latter starts with a differential diagnosis based on the exclusion of both other orofacial chronic pain conditions and painful oral diseases exhibiting muco-sal lesions. However, the occurrence of overlapping/overwhelming oral mucosal pathologies, such as infections, may cause difficulties in the diagnosis ("complicated BMS"). BMS treatment is still unsatisfactory, and there is no definitive cure. As a result, a multidisciplinary approach is required to bring the condition under better control. Importantly, BMS patients should be offered regular follow-up during the symptomatic periods and psychological support for alleviating the psychogenic component of the pain. More research is necessary to confirm the association between BMS and systemic disorders, as well as to investigate possible pathogenic mechanisms involving potential nerve damage. If this goal is to be achieved, a uniform definition of BMS and strict criteria for its classification are mandatory.

Estrogenic activity of tissue conditioners in vitro

OBJECTIVES

In order to assess the estrogenic activities of plasticizers used in tissue conditioners and four commercial tissue conditioners, we carried out in vitro tests.

METHODS

Seven plasticizers and two metabolites were diluted to concentrations ranging from 10(-9) to 10(-4)M. Four commercial tissue conditioners were also diluted to concentrations ranging from 2 x 10(-8) to 2 x 10(-3)g/ml. Estrogenic activities were tested by the E-screen test using MCF-7 cells. When estrogen is present, the cells proliferate. Instead of counting the cells or nuclei directly, cell numbers were assessed by measurement of the total protein content using the sulforhodamine B assay. The liquid compositions of the four commercial tissue conditioners were examined by high-performance liquid chromatography.

RESULTS

n-Butyl benzyl phthalate, dibutyl phthalate, n-butyl phthalyl n-butyl glycolate, di-2-ethylhexyl phthalate and benzyl salicylate significantly increased proliferation of MCF-7 cells. The remaining two plasticizers, di-2-ethylhexyl adipate and benzyl benzoate, as well as two metabolites of dibutyl phthalate and di-2-ethylhexyl phthalate, i.e. monobutyl phthalate and mono-2-ethylhexyl phthalate, respectively, did not increase proliferation of MCF-7 cells at the concentrations tested. Four commercial tissue conditioners, Coe comfort (CC), Tissue Conditioner (TC), Hydro Cast (HC) and Denture Soft (DS) II, significantly increased proliferation of MCF-7 cells. HPLC data revealed the commercial products contained plasticizers: benzyl benzoate and dibutyl phthalate in CC, dibutyl phthalate in TC, n-butyl benzyl phthalate in HC and n-butyl phthalyl n-butyl glycolate in DS II.

SIGNIFICANCE

Except for benzyl benzoate and di-2-ethylhexyl adipate, the plasticizers tested showed estrogenic activity. The four commercial tissue conditioners tested also showed estrogenic activity, and HC showed especially strong estrogenicity.

Contact stomatitis

Contact stomatitis is inflammation or pain of the oral mucosa due to both irritant and allergic substances. Irritants include heat, frictional trauma, and chemicals. Oral flavorings, preservatives, and dental materials are common allergens. Simplification of oral care and avoidance of contactants is the primary mode of therapy. Patch testing to a broad series of antigens may be required to identify specific causes of allergic contact stomatitis.

Burning mouth syndrome

Burning mouth syndrome is the occurrence of oral pain in a patient with a normal oral mucosal examination. It can be caused by both organic and psychologic or psychiatric factors, which can be broken down into local, systemic. psychologic or psychiatric, and idiopathic causes. The most frequently associated conditions are psychiatric (depression, anxiety, or cancerphobia); xerostomia; nutritional deficiency; allergic contact dermatitis; candidiasis; denture-related pain: and parafunctional behavior. Multiple different factors contributing to the oral pain are common, and a systematic approach to the evaluation is important. Identification of correctable causes of BMS should be emphasized and psychiatric causes should not be invoked without thorough evaluation of the patient. A directed history and careful oral examination must be completed to exclude local diseases and identify clues to potential causes. Assessment of medications, psychiatric history and background, and selected laboratory and patch tests may help identify the etiologies of these symptoms. Treatment should be tailored to each patient and may best be managed in a multidisciplinary approach with input from dermatologists, dentists, psychiatrists. otorhinolaryngologists, and primary care providers. A thoughtful and structured evaluation of the patient with BMS has been associated with improvement in about 70% of patients. The remaining patients may benefit from empiric therapy with a chronic pain protocol and continued supportive interactions.

Dental gold alloys and contact allergy

Contact allergy to gold as demonstrated by patch testing is very common among patients with eczematous disease and seems to be even more frequent among patients with complaints from the oral cavity. There is a positive correlation between gold allergy and the presence of dental gold. Gold allergy is often found in patients with non-specific stomatitides as well as in those with lichenoid reactions or with only subjective symptoms from the oral cavity. The therapeutic effect of substituting other dental materials for gold alloys is conspicuous in casuistic reports but less impressive in larger patient materials. The amount of dental gold is correlated qualitatively and quantitatively to the blood level of gold and the effects if any of circulating blood gold are unknown. There is clearly a need for prospective studies in the field and gold sodium thiosulfate is considered an important item in the dental series for patch testing.

Allergic contact stomatitis caused by acrylic monomer in a denture

A 71-year-old edentulous man developed a severely painful red mouth at sites of contact with a new denture. Patch testing showed allergy to samples of the denture material and to 2-hydroxyethyl methacrylate. Patch testing to methyl methacrylate was negative. Prolonged boiling of the denture resulted in reversal of his symptoms and samples of this fully cured denture material produced negative patch tests. While allergy to acrylates is a rare cause of stomatitis, this possibility must be considered in patients presenting with oral symptoms. Material safety data sheets are unreliable in providing information regarding the type of acrylate present in the material. Hence, patch testing should be performed with a battery of acrylate allergens as well as with small samples of the denture material.

Burning mouth syndrome (BMS): controlled open trial of the efficacy of alpha-lipoic acid (thioctic acid) on symptomatology

BACKGROUND

Alpha-lipoic acid (ALA), is a potent antioxidant mitochondrial coenzyme, the trometamol salt of thioctic acid that has been shown in clinical studies to be neuroprotective. This study examined the effect of ALA on the symptomatology of Burning mouth syndrome (BMS).

SUBJECTS AND METHODS

Forty-two patients with BMS and no clinical or laboratory evidence of organic oral disease were divided into two groups (Test and Control) each of 21 subjects, matched for age and sex. The Test group were given ALA (thioctic acid; Tiobec) for 30 days, as 600 mg per day orally for 20 days followed by 200 mg per day for 10 days. The Control group were given cellulose starch 100 mg per day as placebo for 30 days. All BMS patients were reviewed at 10-day intervals and scored for changes in symptomatology.

RESULTS

Significant improvements were shown in the symptomatology of BMS in up to two-thirds of patients with BMS receiving alpha-lipoic acid, in about 15% of those using placebo and also in up to two-thirds of those who, having tried placebo, were switched to ALA.

Gold--a controversial sensitizer. European Environmental and Contact Dermatitis Research Group

Until recently, gold allergy was considered to be extremely rare. Gold has been used and worshipped for thousands of years without any obvious complaints of skin problems, either in those participating in mining and other ways of prospecting, or in those wearing jewellery. When studies on contact allergy to gold sodium thiosulfate were published at the beginning of the 1990s, the allergic nature of the reported positive patch test reactions to gold was questioned. The major argument for such questioning was the lack of demonstrable clinical relevance in most positive reactors. A major reason for the questioning may have been confusion in differentiating between contact allergy and allergic contact dermatitis. To arrive at a diagnosis of allergic contact dermatitis, 3 steps have, in principle, to be fulfilled: (i) establishment of contact allergy; (ii) demonstration of present exposure; (iii) assessment of clinical relevance, i.e., causing or aggravating a contact dermatitis. In this paper, these steps are discussed with regard to gold. With our present knowledge of contact allergy-allergic contact dermatitis, we do not recommend including gold sodium thiosulfate in the standard series. It should be applied for scientific purposes and when allergic contact dermatitis from gold is suspected.

Clinical assessment and outcome in 70 patients with complaints of burning or sore mouth symptoms

OBJECTIVE

To review a series of patients with a burning or sore mouth for elucidation of associated conditions and treatment outcome.

MATERIAL AND METHODS

We retrospectively studied 70 consecutive patients with a burning or sore mouth who were encountered at a tertiary-care center between 1979 and 1992. Clinical and laboratory findings were summarized, and follow-up data were analyzed.

RESULTS

The study cohort of 56 women and 14 men had a mean age of 59 years. They had had a burning or sore mouth for a mean duration of 2.5 years. Multiple etiologic factors for the burning or sore mouth were present in 37% of the study subjects. The most frequently associated conditions were psychiatric disease (30%), xerostomia (24%), geographic tongue (24%), nutritional deficiencies (21%), and allergic contact stomatitis (13%). With a treatment course tailored to the suspected causal factor, 72% of the patients who had follow-up reported improvement.

CONCLUSION

With a directed investigation, one or more causes could be identified in most patients who had a burning or sore mouth. Successful management of these symptoms was possible in a majority of the patients.

Burning mouth syndrome: a review of etiologies

STATEMENT OF PROBLEM

Dental practitioners occasionally have patients present clinically with a history of chief complaint of burning and painful sensations in the oral cavity. Often the patient demonstrates clinically normal mucosa, which can make formulating a diagnosis challenging. This scenario, has been referred to as burning mouth syndrome, a multifactorial syndrome.

PURPOSE

The purpose of this article is to present a review of etiologic factors and clinical implications related to the condition of burning mouth syndrome.

High-performance liquid chromatography assay of N,N-dimethyl-p-toluidine released from bone cements: evidence for toxicity

Five commercially available bone cements were analysed by high-performance liquid chromatography for detecting the residual content of an accelerator, the amine N,N-dimethyl-p-toluidine (DMPT), after curing. It was found that the concentration of DMPT in aqueous extracts decreases with time, being almost absent 7 days after curing. Differences were noticed among the cements; residual DMPT is higher in cements prepared with higher content of the amine. It is verified that DMPT's toxic effect on cell cultures is dose-related; a delay in the cell replication cycle is induced in vitro. Damage is reversible, thus justifying the low bone cement toxicity that is clinically ascertained.

Contact allergies to nickel sulfate, gold sodium thiosulfate and palladium chloride in patients claiming side-effects from dental alloy components

397 patients claiming various subjective symptoms related to dental restoration materials have been tested for the presence of metal allergy. The resultant data have been compared with the corresponding allergies of eczematous patients. The frequency difference of metal allergy in the dental group is statistically significant or close to significance for nickel sulfate, potassium dichromate, cobalt chloride, palladium chloride and gold sodium thiosulfate. The findings suggest that the dental patient group represents a subgroup with a high frequency of metal allergy.

Burning mouth syndrome

Burning mouth syndrome is a common condition particularly affecting elderly women. Numerous precipitating factors are recognized that lead to a burning sensation in clinically normal mucosa. By taking each precipitating factor into account, a favorable treatment outcome usually can be achieved. This article highlights the significance of precipitating factors in burning mouth syndrome and suggests a treatment protocol based on current scientific evidence.

Evaluation of patch test results with denture material series

791 patients, among them 59 dental technicians and 732 other patients, were tested with the denture material series (DMS) recommended by the German Contact Dermatitis Research Group (DKG) in the hospitals of the Information Network of Departments of Dermatology (IVDK) between January 1990 and July 1993. Most frequently, positive reactions occurred to cadmium chloride in both groups. However, there was no evidence at all for relevance of these reactions. Benzoyl peroxide (BPO) ranked 2nd in patch test positivity. Although not statistically significant, reactions were more frequent in dental technicians, who might be exposed to BPO the in working environment. Methyl methacrylate (MMA) and triethylene glycol dimethacrylate (TEGDMA) were common sensitizers in dental technicians but not in other patients. This finding, too, has its explanation in the working process of manufacturing dental prostheses.

The burning mouth syndrome

The burning mouth syndrome is characterized by burning and painful sensations of the mouth in the absence of significant mucosal abnormalities. For patients in whom no causative factor can be identified, empiric antifungal, nutritional, and estrogen replacement therapy can be initiated. If these fail, long-term therapy with antidepressants, benzodiazepines, and clonazepam can be considered. Topical capsaicin and laser therapy have been reported beneficial in a few patients.

The development and course of test reactions to gold sodium thiosulfate

In our department, gold sodium thiosulfate has become the 2nd most common allergen in routinely patch tested dermatitis patients, with a rate around 10%. Test reactions to this compound often appear late, sometimes so late that active sensitization may be suspected. This study was performed to study the time course of the allergic reaction to gold sodium thiosulfate and to elucidate whether late test reactions mean active sensitization. 10 patients with contact allergy to gold sodium thiosulfate (0.5% pet.) were retested epicutaneously (e.c.) and intracutaneously (i.c.) with dilution series. The clinical course was followed for 2 months with initially short intervals, later more extended. During the entire study, 26 positive e.c. reactions were diagnosed. Within the 1st week, 17 (65%) were recorded. 12 reactions (46% of 26) were noted at the ordinary reading, 3 days after test application. After 10 days, another 9 reactions (35%) appeared. The patients with the latter reactions also had positive test reactions within the 1st week. After 2 months, 9 reactions remained. Out of 30 i.c. tests applied, 25 became positive within 1 week. 19 (76%) of these reactions changed in morphology from thin infiltrates to deep nodules. Another 4 nodules appeared in patients with previous negative i.c. tests. All 23 nodules remained after 2 months. E.c. and i.c. test reactions to gold sodium thiosulfate are long-lasting. Positive patch test reactions emerging after 10 days do not automatically imply active sensitization. To diagnose contact allergy to gold sodium thiosulfate, the ordinary reading at day 3 is insufficient; even reading at 1 week is insufficient and must be supplemented by a reading at 3 weeks. All the i.c. test reactions, however, appeared within 1 week and, in several, a dermal nodule was formed.

Burning mouth syndrome

BACKGROUND AND OBJECTIVES

Burning mouth syndrome (BMS) is a frequent process that produces marked oral dysesthetic symptoms. There is controversy over its etiopathogenesis and diagnosis. Therapeutic results are unsatisfactory. The objectives of this study were: (1) to analyze a possible agreement on the definition of BMS; (2) to analyze its cause; (3) to propose a therapeutic scheme that has been shown to be highly effective in our experience and has not been previously reported.

METHODS

Five hundred patients with symptomatology of BMS were retrospectively evaluated with a study protocol, specially designed for this disease. Patients with local or general disease processes that could cause secondary asymptomatic stomatodynia were excluded from the study.

RESULTS

Most of the patients evaluated were women over 60 years of age with oral symptoms, including a sensation of heat and burning, and pain, lasting for months or years, and a history of multiple unsuccessful treatments. The patients showed depression associated with anxiety, with evidence of psychiatric disorders in the family. Based on these findings and eliminating symptomatic painful conditions of the mouth that may stimulate this syndrome, we diagnosed a genuine or basic BMS of psychosomatic origin. Therapies used in the treatment of these neurotic conditions were not always useful. Tranylcypromine associated with anxiolytics and hypnotics in low doses plus the support of psychotherapy by the stomatologist were the most effective treatments.

CONCLUSIONS

The BMS should be defined as a psychosomatic process causing oral dysesthesias for months or years.

Leaching from denture base materials in vitro

Specimens made from denture base materials were leached in Ringer solution and in ethanol. The specimens comprised a heat-cured product processed in two different ways and two cold-cured materials. The organic compounds leaching from the specimens to the solutions were separated, identified, and quantified by a combined gas-chromatography and gas-chromatography/mass-spectrometry technique. Additives and degradation products, possibly made by free radical reactions, were released from the denture base materials. In Ringer solution only phthalates could be quantified. In ethanol solvent, biphenyl, dibutyl phthalate, dicyclohexyl phthalate, phenyl benzoate, and phenyl salicylate were quantified. In addition, copper was found in the ethanol solvent from one of the denture base materials. The amount of leachable organic compounds varies among different materials. Processing temperature influences the initial amount of leachable compounds.

The burning mouth syndrome: lack of a role for contact urticaria and contact dermatitis

BACKGROUND

The burning mouth syndrome is poorly understood and mainly affects postmenopausal women. Dental allergens have seldom explained the burning.

OBJECTIVE

Eight patients (seven women, one man) (mean age 62.5 years) who wore dentures and had the burning mouth syndrome were investigated to determine whether contact urticaria, allergic contact dermatitis, or pressure urticaria played a role. Only patients who had minimal to no erythema of the mucosa were included.

METHODS

A complete blood cell count, fasting chemistry profile, and potassium hydroxide examination and cultures for Candida and dermatophytes were obtained. Contact urticaria and patch testing with control substances were performed with a panel of 25 potential denture allergens.

RESULTS

Complete blood cell counts and fasting chemistry profiles were normal. One positive Candida culture was found, but no improvement in the symptoms was noted after treatment. All patients tested positive to histamine and to at least two of the nonimmunologic urticaria controls. No patient had a positive urticarial reaction to the potential dental allergens. Two patients with nonimmunologic urticaria to cinnamic aldehyde improved with avoidance. All patch tests were negative. In the six patients tested for pressure urticaria, the results were negative.

CONCLUSION

We cannot indict contact dermatitis, contact urticaria, or pressure urticaria as a cause of the burning mouth syndrome in the denture-wearing patient who has a normal-appearing mucosa. The burning symptoms in this syndrome may be secondary to a simple frictional phenomenon of the denture on the mucosa.

High frequency of contact allergy to gold sodium thiosulfate. An indication of gold allergy?

When gold sodium thiosulfate was added to the patch test standard series, positive reactions were obtained in 8.6% of 823 consecutive patients with suspect contact allergy. The test reactions were clinically of an allergic type and, in several cases, long-lasting. There was no correlation with other allergens in the standard series. In a special study on 38 patients with contact allergy to gold sodium thiosulfate, the following principal findings were obtained: positive patch tests to the compound itself in dilute concentration; positive patch tests to potassium dicyanoaurate; negative patch tests to gold sodium thiomalate, sodium thiosulfate, and metallic gold; positive intradermal tests to gold sodium thiosulfate. Our findings make gold sodium thiosulfate the 2nd most common contact allergen after nickel sulfate. It is suggested that a positive skin test to gold sodium thiosulfate represents gold allergy.

Oral manifestations of gold allergy

BACKGROUND

Sensitization to gold in a large group of patients suspected of clinical allergy to this metal has not been reported.

OBJECTIVE

Two hundred patients with symptoms of persistent oral mucosal or cutaneous lesions that were possibly related to allergy to constituents of gold alloys or gold jewelry were patch tested to determine the frequency of sensitization.

METHODS

Patch testing was performed with the European standard series and a series of dental materials including three different salts of gold. A persistent papular reaction to gold-(tri)chloride was considered a positive reaction.

RESULTS

In 17 patients (8.5%, all women, mean age 50.2 years) persistent papular patch test reactions to both 0.5% and 1.0% gold(tri)chloride were observed. In five of seven patients with oral lichen planus (OLP) and in one of six patients with the burning mouth syndrome, gold in the dentures was replaced. Particularly in patients with OLP, a significant but variable improvement was observed. In all cases in which gold was replaced and improvement occurred, the patients were sensitized to 0.5% gold(tri)chloride. One patient with allergic contact stomatitis and one patient with allergic contact dermatitis healed completely after gold had been replaced.

CONCLUSION

Sensitization to gold should be considered as a possible cause of allergic contact dermatitis and allergic contact stomatitis as well as a pathogenic or triggering factor in OLP.