The 2020 International Classification of Orofacial Pain defined burning mouth syndrome (BMS) as a chronic orofacial pain condition, characterized by a burning and painful sensation of the oral mucosa, usually on the anterior two-thirds or tip of the tongue. Exclusion of other conditions is an important component of diagnosis which can often prove challenging. The pathophysiology is not completely understood and management of burning mouth syndrome is similar to other neuropathic pain conditions. A number of different topical pharmotherapeutic approaches have been used to for burning mouth syndrome with variable success.
The aim of this review was to assess the effectiveness of topical interventions in the management of burning mouth syndrome (BMS), based on the core outcome domains recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT).
Methods
The review was registered in PROSPERO as an updating of an earlier review. Searches were conducted in the Cochrane Database / Cochrane Central, PubMed, Web of Science, PsycINFO and Google Scholar databases. Randomised controlled trials (RCTs) of topical interventions for burning mouth syndrome (BMS) were considered. Studies needed to have fulfilled the International Association for the Study of Pain (IASP) (Merskey & Bogduk,1994) diagnostic criteria and reported one of the IMMPACT recommended outcome measures (Dworkin et al 2005). Studies published before 1994 and languages other than English were excluded as were cluster RCTs. For cross-over RCTs only the first period of intervention was assessed because of potential carry-over effects.
Study screening and selection was conducted independently by 4 reviewers and a librarian. Data was abstracted by a single author and cross checked by 2 reviewers. Two reviewers independently assessed risk of bias using the Cochrane domains-based tool. A narrative summary was presented as meta-analysis was not conducted because of study heterogeneity. The Grading of Recommendation Assessment Development and Evaluation (GRADE) framework was used to assess the certainty of the evidence.
Results
- 8 RCTs (6 parallel, 2 cross-over) involving a total of 358 patients met the inclusion criteria
- 3 Studies were conducted in Spain and one in each of Brazil, Denmark, France, Italy and Sweden.
- The patients ages ranged from 7 and 72.7 years with a female to male ratio of 7.49: 1.
- 2 RCTs evaluated the effect of clonazepam tablets (1 and 0.5 mg) with the other 5 trials evaluating different agents (benzydamine hydrochloride oral rinse 0.15%, capsaicin oral rinse, urea, bupivacaine 5 mg local anaesthetic lozenge, aloe vera and chamomile 2% gel).
- Treatment duration for the trials ranged from 1 to 24 weeks.
- 1 study was considered to be at low risk of bias, 3 at high risk and at unclear risk.
- 6 out of the eight RCTs reported changes in the pain intensity using a visual analogue scale (VAS).
- 7 out of 8 of the studies reported on adverse events.
Conclusions
The authors concluded: –
This systematic review highlights the need for application of standardized outcome measures to future RCTs. At the present time, there is lack of moderate-strong evidence on short- and long-term outcomes to support or refute the use of any particular topical intervention in managing BMS. Future RCTs with standardized outcome measures are needed.
Comments
A 2016 Cochrane review looked at interventions for BMS including 23 RCTs (Dental Elf – 28th Nov 2016) finding that the overall quality of the evidence for effectiveness was very low for all interventions and all outcomes. More recently we looked at a review by Ślebioda et al (Dental Elf – 18th Jan 2021) which included 30 studies. This review has only included English language studies and studies that reported core outcome domains recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT). The review therefore includes only 8 studies with just 6 being common to both reviews. All 3 reviews suffer from the significant heterogeneity in the types of interventions dosages and duration of treatment as well as small sample sizes. The reviewer authors decision to assess studies based on the IMMPACT core outcomes model is welcomed but more widespread use of these core outcomes is needed in the primary studies. The reviews to date do seem to suggest some interventions are more effective and consideration should be given to undertaking larger well conducted and reported RCTs of these involving longer treatments, standard diagnostic criteria and core outcome assessments.
Links
Primary Paper
Goncalves S, Carey B, Farag AM, Kuten-Shorrer M, Natto ZS, Ariyawardana A, Mejia LM, Chmieliauskaite M, Miller CS, Ingram M, Nasri-Heir C, Sardella A, Carlson CR, Klasser GD, O’Neill F, Albuquerque R. WWOM VII: Effectiveness of topical interventions in the management of burning mouth syndrome: A systematic review. Oral Dis. 2022 Jul 4. doi: 10.1111/odi.14297. Epub ahead of print. PMID: 35781729.
Other references
Merskey, H., & Bogduk, N.(1994). Classiication of chronic pain: descriptions of chronic pain syndromes and definitions of pain terms/prepared by the Task Force on Taxonomy of the international Association for the Study of Pain (2nd ed., pp. 742). IASP Press.
Dworkin RH, Turk DC, Farrar JT, Haythornthwaite JA, Jensen MP, Katz NP, Kerns RD, Stucki G, Allen RR, Bellamy N, Carr DB, Chandler J, Cowan P, Dionne R, Galer BS, Hertz S, Jadad AR, Kramer LD, Manning DC, Martin S, McCormick CG, McDermott MP, McGrath P, Quessy S, Rappaport BA, Robbins W, Robinson JP, Rothman M, Royal MA, Simon L, Stauffer JW, Stein W, Tollett J, Wernicke J, Witter J; IMMPACT. Core outcome measures for chronic pain clinical trials: IMMPACT recommendations. Pain. 2005 Jan;113(1-2):9-19. doi: 10.1016/j.pain.2004.09.012. PMID: 15621359.
Dental Elf – 18th Jan 2021
Dental Elf – 2nd Jul 2021
Dental Elf – 12th Jun 2017
Dental Elf – 28th Nov 2016
Burning mouth syndrome: insufficient evidence for effectiveness of current treatments
Picture Credits
Photo by Max Langelott on Unsplash
