Neuropathic and Psychogenic Components of Burning Mouth Syndrome: A Systematic Review.

The pathophysiology of primary burning mouth syndrome (BMS) has been extensively debated but is poorly understood despite a large number of hypotheses attempting to explain its etiopathogenic mechanisms. The aim of the present work was to systematically review papers that could provide arguments in favour of the neuropathic and psychogenic components of primary BMS for a better understanding of the disease. This systematic review (SR) was registered in PROSPERO (CRD42021224160). The search was limited to articles in English or French from 1990 to 01 December 2020. A total of 113 articles were considered for data extraction. We divided them into four subgroups: pharmacological and nonpharmacological management studies (n = 23); neurophysiological studies (n = 35); biohistopathological studies (n = 25); and questionnaire-based studies (n = 30). Several of these studies have shown neuropathic involvement at various levels of the neuraxis in BMS with the contribution of quantitative sensory testing (QST), functional brain imaging, and biohistopathological or pharmacologic studies. On the other hand, the role of psychological factors in BMS has also been the focus of several studies and has shown a link with psychiatric disorders such as anxiety and/or depression symptoms. Depending on the patient, the neuropathic and psychogenic components may exist simultaneously, with a preponderance of one or the other, or exist individually. These two components cannot be dissociated to define BMS. Consequently, BMS may be considered nociplastic pain.

Conhecimento científico produzido sobre a Síndrome da Ardência Bucal nos últimos cinco anos / Scientific knowledge produced about Bucal Ardence Syndrome in the last five years

Objetivo: realizar revisão integrativa da literatura sobre a Síndrome da Ardência Bucal (SAB). Materiais e Método: trata-se de uma revisão integrativa da literatura sobre a SAB nos últimos cinco anos. Utilizou-se as bases de dados Medline, SciELO e Lilacs para a pesquisa, empregando de forma combinada os descritores relacionados à temática. Como critérios de inclusão, decidiu-se selecionar publicações sobre a temática que estivessem disponíveis para leitura em qualquer idioma dos últimos cinco anos. Foram excluídos os estudos sem relação com o tema. Resultados: após análise, apenas 42 estudos foram selecionados para esta revisão. A maior parte dos artigos era publicada em inglês, porém, foi o Brasil que apresentou o maior número de publicações. As pesquisas avaliadas demonstraram os seguintes resultados: o sexo feminino é o mais acometido; maior prevalência acima dos 60 anos; dor, queimação e xerostomia são os sintomas mais relatados. O laser foi bastante relatado como terapia, além do uso de fármacos. Conclusão: a revisão apresentada neste artigo constatou que a maioria dos artigos, apesar de oriundos do Brasil, foi publicada no idioma inglês. A maioria dos trabalhos destacou que indivíduos do sexo feminino acima dos 60 anos são mais acometidos. Pacientes com SAB apresentam dor e queimação em língua e palato, principalmente. Fatores psicológicos e gastrointestinais podem estar associados ao aparecimento desta síndrome, e os usos do laser e de fármacos fitoterápicos, ou não, parecem melhorar o quadro clínico dos indivíduos acometidos.(AU)

Objective: to perform an integrative review of the literature on Burning Mouth Syndrome (BMS). Materials and Method: This is an integrative review of the literature on Burning Mouth Syndrome over the last five years. The Medline, SciELO, and Lilacs databases were used for the research, using the descriptors related to the topic in combination. The inclusion criteria consisted of publications on the topic that were available for reading in any language over the last five years. Studies unrelated to the topic were excluded. Results: After the analysis, only 42 studies were selected for this review. Most articles were published in English but Brazil had the highest number of publications. The studies evaluated showed the following results: women are the most affected; highest prevalence over 60 years old; and pain, burning, and xerostomia are the most reported symptoms. The laser was extensively reported as therapy, as well as the use of other drugs. Conclusion: The review presented in this article found that most studies were published in Brazil but in the English language. Most studies highlighted that women over 60 years old are more affected. Patients with BMS experience pain and burning especially in the tongue and palate. Psychological and gastrointestinal factors may be associated with the onset of this syndrome, and the use of laser and other drugs, either herbal medicines or not, seems to improve the clinical condition of the individuals affected.(AU)

Therapeutic Applications of Capsaicin in Upper Airways.

BACKGROUND: Capsaicin (8-methyl-N-vanillyl-6-nonenamide) is the substance responsible of the irritation caused by the contact of chili peppers with the skin or mucous membranes. This protoalkaloid acts by stimulating the transient receptor potential cation channel subfamily V member 1 (TRPV1), which is mainly expressed by nociceptive fibers of peripheral sensory neurons, but is also present in the central nervous system, and in some non-neuronal cells. Following the initial, intense neuronal excitation, a brief refractory period occurs. However, repeated and massive exposures to capsaicin can impair nociceptive fiber function for weeks or months. During this lapse of time, disorders related to the hyperreactivity of peripheral nociceptors are abolished or greatly reduced. Capsaicin has been utilized to treat several diseases of upper airways. OBJECTIVE: The objective of this review was to report the latest findings on the use of Capsaicin in the treatment of upper airway diseases. RESULTS: Capsaicin effectiveness has been proved in non allergic rhinitis. Some studies suggest that this substance may be also effective in nasal polyposis and in the burning mouth syndrome. No clear evidence has been obtained about its use in allergic rhinitis. CONCLUSION: To date, the use of capsaicin to treat upper airway diseases is still limited in clinical practice. This may originate by the lack of strong, conclusive evidences of its effectiveness, by the variety of therapeutic schemes used in literature, and finally by the unpleasant effects of the exposure to capsaicin, which are only partly relieved by the pretreatment with local anesthetics.

Combined Acupuncture and Auriculotherapy in Burning Mouth Syndrome Treatment: A Preliminary Single-Arm Clinical Trial.

BACKGROUND: Burning mouth syndrome (BMS) is a chronic pain disorder that is difficult to diagnose and refractory to treatment; it is more prevalent in pre- and postmenopausal women. Acupuncture and auriculotherapy have been suggested as options for the treatment of pain because they promote analgesia and allow for the reduction of symptoms with lower doses of drugs; this leads to greater patient compliance with treatment and has a positive effect on quality of life. Clinical trials investigating the effectiveness of acupuncture in the treatment of BMS are scarce in the literature. OBJECTIVE: To investigate the effect of combined acupuncture and auriculotherapy on pain management and quality of life in patients with BMS. METHODS: Sixty patients with BMS were subjected to a thorough differential diagnosis. Of these, 12 met the inclusion criteria and agreed to participate. Eight patients completed treatment with acupuncture and auriculotherapy using a previously established protocol. The outcome variables were analyzed before and after treatment: pain/burning (visual analog scale; VAS), salivary flow (unstimulated sialometry), and quality of life (Short-Form Oral Health Impact Profile [OHIP-14]). Two-year follow-up was carried out by assessing VAS and OHIP-14. RESULTS: The intensity of pain/burning decreased significantly after the first treatment sessions, as shown by low values on the VAS (0-2) and a subjective indicator of quality of life (mean = 5.37 ± 3.50). There was no relationship between salivary flow and the intensity of pain/burning. At 2-year follow-up, no statistically significant difference was observed for VAS, but improvement on OHIP-14 was seen. CONCLUSIONS: Combined acupuncture/auriculotherapy was effective in reducing the intensity of burning and improving quality of life. There was no relationship between salivary flow and the intensity of burning mouth. Patients' status improved after acupuncture and auriculotherapy at 2-year follow-up.

Salivation quantum--stomatopyrosis--autogenic training.

Stomatopyrosis of 'burning mouth' syndrome, in a narrower sense of definition, is a condition characterized by sensation of burning and heating in mouth, despite its normal mucosa. This research has been directed towards treatment of stomatopyrosis, putting emphasis on the implementation of psychopharmacotherapy and psychotherapy. The research was conducted on altogether 120 respondents suffering from stomatopyrosis. The respondents were divided into two equal groups: each one comprising 60 members. All the respondents were treated by means of a standard topical therapy. All the patients were assessed clinically and by means of psychological tests measuring depression and anxiety four times: once before the treatment, after one month, after two months and after four months since the beginning of the treatment. The acquired data were afterwards statistically processed. When grading the symptoms on VAS, i.e. visual analogous scale, the subjective assessment of symptoms was marked as 7-8 cm, which shows a high degree of burning sensation. According to our study, the quantity of saliva, which was at the beginning of the research slightly decreased, normalized after the treatment. Apart from the clinical investigation of stomatopyrosis, we applied Depression and Anxiety questionnaires. On the basis of our research, we have concluded the following: the comorbidity of stomatopyrosis with the phenomena of anxiety and depression proves that, among other factors, there is a psychogenic aetiology of this disease. Autogenic training, which is a psychotherapeutic anxiolytic technique, is a therapy of choice for stomatopyrosis, which contributes not only to the elimination of oral complaints, but to the emotional rehabilitation of the patients as well, and to the reduction of dryness in the mouth.

Síndrome de ardor bucal: actualización diagnóstica y terapéutica / Burning mouth syndrome: diagnostic and therapeutic actualisation

El síndrome de boca ardiente (SBA) es una entidad patológica caracterizada por la presencia de síntomas crónicos de ardor o dolor en la mucosa bucal clínicamente normal. El SBA afecta principalmente a mujeres peri y posmenopáusicas. Su causa es desconocida, pero su relación con una compleja asociación de factores biológicos y psicológicos hace suponer una etiología multifactorial. Aunque se han encontrado tratamientos eficaces en casos particulares, se sigue buscando un tratamiento que resulte eficaz en la mayoría de los casos. Esta revisión hace especial referencia a los factores etiológicos y al tratamiento del síndrome (AU)

The burning mouth syndrome (BMS) is characterized by the presence of chronic symptoms of burning or paining clinically normal oral mucosa. This syndrome primarily affects peri and postmenopausal women. The cause is unknown, but the relationship between the BMS and a complex association of biological and psychological factors suggest a multifactorial etiology. Although some treatments have been found effective in particular cases, the clinical searchers are still looking for a treatment that can be effective in most cases. This review makes particular reference to the etiological factors and the treatment of the síndrome (AU)

Cerebral activation during thermal stimulation of patients who have burning mouth disorder: an fMRI study.

The pathophysiology of burning mouth disorder (BMD) is not clearly understood, but central neuropathic mechanisms are thought to be involved. The aim of this study was to gain insight into the pathophysiology associated with BMD by using functional magnetic resonance imaging (fMRI). Areas of brain activation following thermal stimulation of the trigeminal nerve of eight female patients with BMD (mean age 49.1+/-10.1) were mapped using fMRI and compared with those of eight matched pain-free volunteers (mean age 50.3+/-12.3). Qualitative and quantitative differences in brain activation patterns between the two study groups were demonstrated. BMD patients displayed greater fractional signal changes in the right anterior cingulate cortex (BA 32/24) and bilateral precuneus than did controls (p<0.005). The control group showed larger fractional signal changes in the bilateral thalamus, right middle frontal gyrus, right pre-central gyrus, left lingual gyrus, and cerebellum than did the BMD patients (p<0.005). In addition, BMD patients had less volumetric activation throughout the entire brain compared to the control group. Overall, BMD patients displayed brain activation patterns similar to those of patients with other neuropathic pain conditions and appear to process thermal painful stimulation to the trigeminal nerve qualitatively and quantitatively different than pain-free individuals. These findings suggest that brain hypoactivity may be an important feature in the pathophysiology of BMD.

[Preliminary protocol for systemic administration of capsaicin for the treatment of the burning mouth syndrome]. / Protocollo preliminare sull'utilizzo della capsaicina sistemica per la terapia della Sindrome della Bocca Bruciante.

AIM: Burning mouth syndrome could be considered an expression of atypical facial pain. The recent neuropathological findings in BMS may suggest the need for alternative therapies. This paper aims to evaluate if systemic capsaicin could be used for BMS the- rapy. METHODS: Eighty-four BMS patients (19 males and 63 females, aged 36 to 74 years, mean 54.6) were referred to the Oral Medicine and Oral Pathology Department, Dental University Institute, Milan-Bicocca University. They were divided in 2 groups: 1(st) Group: the first group (42 patients) received 3 capsules of capsaicin (50 mg of powder of red pepper with 0,25% of capsaicin) a day for one month. 2(nd) Group: the control group (42 patients) received 3 capsules of placebo (empty capsules) a day for one month. The intensity of pain was measured on the visuo-analogical scale VAS. T test of Student was applied to analyse results of VAS. P values of less than 0.05 were interpreted as significant, and the level in confidence intervals was 95%. RESULTS: Significant differences were noted between the two groups at the end of our study (p<0.05). No important side effects were reported. CONCLUSION: Systemic capsaicin could be considered a successful therapeutical approach for BMS patients.

Clinical psychiatric assessment of patients with burning mouth syndrome resisting oral treatment.

Of 100 consecutive patients referred for investigation of symptoms related to oral galvanism, 18 with persisting symptoms of burning mouth syndrome (BMS) remained after investigation and treatment (Hugoson 1986). In addition to the oral and medical treatment, 16 (14 women, 2 men) of these patients underwent psychiatric investigation. The results of this investigation are presented in this report. The psychiatric investigation was performed as a semistructured interview, elucidating current symptoms, the patient's opinion as to the onset and causes, previous illnesses and psycho-social conditions. Two hours were reserved for each patient interviewed with the aim of obtaining a holistic picture of each individual. The patients with refractory burning mouth syndrome did not differ from the others with respect to oral status, salivary secretion or calculated galvanic currents. No patient had burning mouth as the only symptom, all reporting many symptoms from different organs. Three patients had had symptoms for at least 20 years, 9 for 5-10 years and 4 patients for less than 4 years. Seven patients related the onset of symptoms to oral treatment. Thirteen of the patients reported one or more medical diagnoses and 10 patients were taking 1-3 medicines. Ten patients reported significant negative experiences in connection with previous contacts with the health services and several considered themselves wrongly diagnosed and treated. Most of the patients had experienced catastrophes in their lives in the form of stillborn children or children born with various handicaps, children injured in accidents or prolonged social problems. One patient was judged to have somatic causes of the symptoms, 8 patients somatic and psychological causes, 6 patients psychological causes and in 1 patient the cause was unknown. Three cases are presented in more detail.