Herbal derivatives in the management of mouth opening in oral submucous fibrosis-A network meta-analysis

Curcumin in the treatment of oral submucous fibrosis: a systematic review and meta-analysis of randomized controlled trials

The objective was to evaluate the efficacy of curcumin in improving mouth opening (MO), burning sensation (BS), and tongue protrusion (TP) symptoms in patients with oral submucous fibrosis (OSF). An electronic search up to November 2022 was conducted in the PubMed, Web of Science, Embase, EBSCO, ProQuest, and Cochrane Library databases to identify studies using curcumin in the treatment of OSF with comparison to control groups (drugs previously proven to be effective for OSF treatment) or placebo. Only randomized controlled trials (RCTs) were considered. RevMan 5.3 software was used for the meta-analysis. Thirteen RCTs met the eligibility criteria and were included in the analysis. The results showed no significant improvement in MO (in millimetres) for curcumin when compared to control at 1 month (P = 0.91), 2 months (P = 0.54), 3 months (P = 0.56), or 6 months (P = 0.17) of treatment. There was no significant difference in BS (assessed using a visual analogue scale) between curcumin and control after 1 month (P = 0.05), 2 months (P = 0.64), 3 months (P = 0.13), or 6 months (P = 0.56) of treatment. Compared with the control groups, treatment with curcumin for 1 month (P = 0.32), 2 months (P = 0.07), and 3 months (P = 0.14) did not significantly improve the TP (in millimetres) of patients. The administration of curcumin, whether topically applied or taken orally, did not confer statistically significant improvements in MO, BS, or TP in comparison to the control treatments, among patients with OSF. The results of this meta-analysis showed that compared to placebo, the application of curcumin for 6 months markedly alleviated BS (P < 0.001). Curcumin treatment in OSF reaches a clinically effective range, but more bioavailability-centred outcomes should be reported. Robust multicentre RCTs are warranted to elucidate the efficacy of curcumin in improving specific outcomes like MO, BS, and TP in patients with this condition. Defining the therapeutic role of this natural compound may provide an effective botanical alternative for managing OSF.

Interventions for managing oral submucous fibrosis

BACKGROUND

Oral submucous fibrosis (OSF) is a chronic disease of the oral cavity that causes progressive constriction of the cheeks and mouth accompanied by severe pain and reduced mouth opening. OSF has a significant impact on eating and swallowing, affecting quality of life. There is an increased risk of oral malignancy in people with OSF. The main risk factor for OSF is areca nut chewing, and the mainstay of treatment has been behavioural interventions to support habit cessation. This review is an update of a version last published in 2008.

OBJECTIVES

To evaluate the benefits and harms of interventions for the management of oral submucous fibrosis.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 5 September 2022.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) of adults with a biopsy-confirmed diagnosis of OSF treated with systemic, locally delivered or topical drugs at any dosage, duration or delivery method compared against placebo or each other. We considered surgical procedures compared against other treatments or no active intervention. We also considered other interventions such as physiotherapy, ultrasound or alternative therapies.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were 1. participant-reported resumption of normal eating, chewing and speech; 2. change or improvement in maximal mouth opening (interincisal distance); 3. improvement in range of jaw movement; 4. change in severity of oral/mucosal burning pain/sensation; 5.

ADVERSE EFFECTS

Our secondary outcomes were 6. quality of life; 7. postoperative discomfort or pain as a result of the intervention; 8. participant satisfaction; 9. hospital admission; 10. direct costs of medication, hospital bed days and any associated inpatient costs for the surgical interventions. We used GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We included 30 RCTs (2176 participants) in this updated review. We assessed one study at low risk of bias, five studies at unclear risk of bias and 24 studies at high risk of bias. We found diverse interventions, which we categorised according to putative mechanism of action. We present below our main findings for the comparison 'any intervention compared with placebo or no active treatment' (though most trials included habit cessation for all participants). Results for head-to-head comparisons of active interventions are presented in full in the main review. Any intervention versus placebo or no active treatment Participant-reported resumption of normal eating, chewing and speech No studies reported this outcome. Interincisal distance Antioxidants may increase mouth opening (indicated by interincisal distance (mm)) when measured at less than three months (mean difference (MD) 3.11 mm, 95% confidence interval (CI) 0.46 to 5.77; 2 studies, 520 participants; low-certainty evidence), and probably increase mouth opening slightly at three to six months (MD 8.83 mm, 95% CI 8.22 to 9.45; 3 studies, 620 participants; moderate-certainty evidence). Antioxidants may make no difference to interincisal distance at six-month follow-up or greater (MD -1.41 mm, 95% CI -5.74 to 2.92; 1 study, 90 participants; low-certainty evidence). Pentoxifylline may increase mouth opening slightly (MD 1.80 mm, 95% CI 1.02 to 2.58; 1 study, 106 participants; low-certainty evidence). However, it should be noted that these results are all less than 10 mm, which could be considered the minimal change that is meaningful to someone with oral submucous fibrosis. The evidence was very uncertain for all other interventions compared to placebo or no active treatment (intralesional dexamethasone injections, pentoxifylline, hydrocortisone plus hyaluronidase, physiotherapy). Burning sensation Antioxidants probably reduce burning sensation visual analogue scale (VAS) scores at less than three months (MD -30.92 mm, 95% CI -31.57 to -30.27; 1 study, 400 participants; moderate-certainty evidence), at three to six months (MD -70.82 mm, 95% CI -94.39 to -47.25; 2 studies, 500 participants; moderate-certainty evidence) and at more than six months (MD -27.60 mm, 95% CI -36.21 to -18.99; 1 study, 90 participants; moderate-certainty evidence). The evidence was very uncertain for the other interventions that were compared to placebo and measured burning sensation (intralesional dexamethasone, vasodilators). Adverse effects Fifteen studies reported adverse effects as an outcome. Six of these studies found no adverse effects. One study evaluating abdominal dermal fat graft reported serious adverse effects resulting in prolonged hospital stay for 3/30 participants. There were mild and transient general adverse effects to systemic drugs, such as dyspepsia, abdominal pain and bloating, gastritis and nausea, in studies evaluating vasodilators and antioxidants in particular.

AUTHORS' CONCLUSIONS

We found moderate-certainty evidence that antioxidants administered systemically probably improve mouth opening slightly at three to six months and improve burning sensation VAS scores up to and beyond six months. We found only low/very low-certainty evidence for all other comparisons and outcomes. There was insufficient evidence to make an informed judgement about potential adverse effects associated with any of these treatments. There was insufficient evidence to support or refute the effectiveness of the other interventions tested. High-quality, adequately powered intervention trials with a low risk of bias that compare biologically plausible treatments for OSF are needed. It is important that relevant participant-reported outcomes are evaluated.

Methodological quality of network meta-analysis in dentistry: a meta-research

This meta-research aimed to provide an overview of the methodological quality and risk of bias of network meta-analyses (NMA) in dentistry. Searches for NMA of randomized clinical trials with clinical outcomes in dentistry were performed in databases up to January 2022. Two reviewers independently screened titles/abstracts, selected full texts, and extracted the data. The adherence to PRISMA-NMA reporting guideline, the AMSTAR-2 methodological quality tool, and the ROBIS risk of bias tool were assessed in the studies. Correlation between the PRISMA-NMA adherence and the AMSTAR-2 and ROBIS results was also investigated. Sixty-two NMA studies were included and presented varied methodological quality. According to AMSTAR-2, half of the NMA presented moderate quality (n = 32; 51.6%). The adherence to PRISMA-NMA also varied. Only 36 studies (58.1%) prospectively registered the protocol. Other issues lacking of reporting were data related were data related to the NMA geometry and the assessment of results consistency, and the evaluation of risk of bias across the studies. ROBIS assessment showed a high risk of bias mainly for domains 1 (study eligibility criteria) and 2 (identification and selection of studies). Correlation coefficients between the PRISMA-NMA adherence and the AMSTAR-2 and ROBIS results showed moderate correlation (rho < 0.6). Overall, NMA studies in dentistry were of moderate quality and at high risk of bias in several domains, especially study selection. Future reviews should be better planned and conducted and have higher compliance with reporting and quality assessment tools.

Comparative Effectiveness of Medicinal Interventions for Oral Submucous Fibrosis: A Network Meta-Analysis

OBJECTIVES

This network meta-analysis presents an exhaustive description and comparison of the available medical interventions for the management of oral submucous fibrosis (OSMF).

MATERIALS AND METHODS

A systematic review and network meta-analysis was conducted after registration with PROSPERO. (PROSPERO ID CRD42022303441). Databases (PubMed, Cochrane, EMBASE, Web of Science, and others) were searched for randomized clinical trials (RCT) trials from inception till September 2022 for the medical interventions in OSMF. The primary outcome was the improvement in mouth opening. The secondary outcomes were improvement in burning sensation, tongue protrusion, and cheek flexibility. The interventions were ranked according to their efficacy based on the surface under the cumulative ranking.

RESULTS

47 studies including 2393 patients were assessed for quantitative analysis. For mouth opening, the combined treatment with steroid, hyaluronidase, and antioxidant was most effective [MD, 7.05 (95%CI 1.76,12.34)], followed by the combination of oral antioxidants with injectable steroids, [MD, 3.80 (95%CI -0.44,8.03)]. Additionally, the combined treatment with steroid, hyaluronidase, and antioxidant was most effective in reducing the burning sensation [MD, -8.62(-10.95,-6.30)], followed by aloe vera [MD, -8.45(-10.40,-6.49)] and pentoxifylline [MD -7.57(-9.46,-5.68)]. For tongue protrusion, curcumin was most effective followed by antioxidants. Most of the drugs used were reported to cause negligible or mild adverse effects.

CONCLUSION

This network meta-analysis reported the efficacy of medicinal interventions in OSMF patients compared to the placebo in the improvement of mouth opening and burning sensation, and cheek flexibility. The methodological quality of included RCTs was low. Well-designed studies are recommended to obtain strong evidence.

Mechanistic Investigation of Curcuma Protection against Oral Submucous Fibrosis

Objective

Oral submucous fibrosis (OSMF) is a chronic, fibrotic disease that affects the oral cavity, showing a high rate of malignant transformation. Curcuma exerts therapeutic potentials in many diseases including OSMF. However, the potential targets and pathways to explain the therapeutic effects of curcuma on OSMF are outside the scope of present knowledge. Herein we intend to reveal the predictive targets and potential pathways of curcuma against OSMF by a network pharmacology-based approach followed by molecular docking technology.

Methods

We searched the SymMap, GeneCards, and OMIM database to obtain curcuma and OSMF common targets. The protein-protein interaction (PPI) of curcuma and OSMF common targets were then analyzed, followed by functional enrichment analysis. The best binding mode of curcuma and target proteins was analyzed by molecular docking technology.

Results

We collected 290 putative targets of curcuma molecules and 600 known therapeutic targets of OSMF, with 64 curcuma and OSMF common targets sorted out. In the PPI network, there were 63 nodes with 922 edges. The node indicates protein and the line indicates PPI relation. The most enriched GO term in the BP level is “gland development”, followed by “cellular response to chemical stress”, and then “response to oxygen levels”, while the most enriched GO term in CC and MF is “membrane raft” and “cytokine receptor binding”, respectively. We also found 131 KEGG pathways significantly enriched by curcuma and OSMF common targets. The binding energy of curcuma to ALB, TNF, TP53, IL6, and VEGFA was −9.5 kcal/mol, −3.9 kcal/mol, −3.5 kcal/mol, −3.6 kcal/mol, and −8.9 kcal/mol, respectively, which suggested ALB and VEGFA were regarded as main targets involving in the potential mechanism of curcuma against OSMF.

Conclusion

The present study illustrated that the therapeutic effects of curcuma on OSMF were achieved by targeting ALB and VEGFA, which giving reference to further drug design and development for OSMF.

Molecular Mechanisms of Malignant Transformation of Oral Submucous Fibrosis by Different Betel Quid Constituents-Does Fibroblast Senescence Play a Role?

Betel quid (BQ) is a package of mixed constituents that is chewed by more than 600 million people worldwide, particularly in Asia. The formulation of BQ depends on a variety of factors but typically includes areca nut, betel leaf, and slaked lime and may or may not contain tobacco. BQ chewing is strongly associated with the development of potentially malignant and malignant diseases of the mouth such as oral submucous fibrosis (OSMF) and oral squamous cell carcinoma (OSCC), respectively. We have shown recently that the constituents of BQ vary geographically and that the capacity to induce disease reflects the distinct chemical composition of the BQ. In this review, we examined the diverse chemical constituents of BQ and their putative role in oral carcinogenesis. Four major areca alkaloids—arecoline, arecaidine, guvacoline and guvacine—together with the polyphenols, were identified as being potentially involved in oral carcinogenesis. Further, we propose that fibroblast senescence, which is induced by certain BQ components, may be a key driver of tumour progression in OSMF and OSCC. Our study emphasizes that the characterization of the detrimental or protective effects of specific BQ ingredients may facilitate the development of targeted BQ formulations to prevent and/or treat potentially malignant oral disorders and oral cancer in BQ users.