Oral mucosal disease: Lichen planus

Expression of epithelial growth factor receptor as a protein marker in oral reticular and erosive lichen planus

BACKGROUND

Oral lichen planus (OLP) is a chronic inflammatory mucosal disease that is classified as a premalignant condition. Epithelial growth factor receptor (EGFR) is associated with tumorigenesis and tumor progression and is overexpressed in several oral malignant disorders. Despite the association of EGFR overexpression with oral potentially malignant lesions, few studies have analyzed its expression in OLP, showing controversial results. This study aimed to compare the expression of EGFR as a protein marker in Reticular and Erosive OLP.

METHODS

This descriptive-analytical cross-sectional was conducted on 15 paraffin blocks of reticular lichen planus lesions, 16 paraffin blocks of erosive OLP lesions, and 8 paraffin blocks of inflammatory fibrous hyperplasia lesions as the control group (39 in total). After immunohistochemical staining for EGFR, samples were simultaneously observed by two maxillofacial pathologist, and the percentage of stained cells, intensity of staining, pattern of staining, and the location of stained cells were obtained.

RESULTS

The Mann-Whitney-U test showed that there was no significant difference in the mean percentage of stained cells between erosive OLP and reticular OLP (P-value = 0.213) and between reticular OLP and control group (P-value = 0.137), but there was a significant difference between erosive OLP and control group (P-value = 0.035). Fisher's exact test showed that there was no significant difference between the frequency distribution of staining patterns in three types of lesions (P-value = 0.90). Kruskal-Wallis test showed that there was no significant difference between the intensity of staining in the three groups (P-value = 0.19) and also there was no significant difference between the location of stained cells in different layers of the epithelium in the three groups (P-value = 0.90).

CONCLUSIONS

The results of this study showed that in comparison of reticular OLP, erosive OLP, and the control group there was a significant difference just between erosive OLP and control group in the percentage of stained cells.

Role of Oral Microbiota Dysbiosis in the Development and Progression of Oral Lichen Planus

Oral lichen planus (OLP) is a chronic inflammatory autoimmune disease of the oral cavity with malignant potential affecting 1.01% of the worldwide population. The clinical patterns of this oral disorder, characterized by relapses and remissions of the lesions, appear on buccal, lingual, gingival, and labial mucosa causing a significant reduction in the quality of life. Currently, there are no specific treatments for this disease, and the available therapies with topical and systemic corticosteroids only reduce symptoms. Although the etiopathogenesis of this pathological condition has not been completely understood yet, several exogenous and endogenous risk factors have been proposed over the years. The present review article summarized the underlying mechanisms of action involved in the onset of OLP and the most well-known triggering factors. According to the current data, oral microbiota dysbiosis could represent a potential diagnostic biomarker for OLP. However, further studies should be undertaken to validate their use in clinical practice, as well as to provide a better understanding of mechanisms of action and develop novel effective intervention strategies against OLP.

Assessment of TNF-α (-857 C/T) gene polymorphism in oral lichen planus disease: A case-control study

Background and aims

Oral lichen planus (OLP) is an inflammatory mucocutaneous disorder with an immune-mediated pathogenesis. The tumor necrosis factor-α (TNF-α) level in the serum of OLP patients is significantly higher than in the control group. TNF-α-857 C/T polymorphism can be related to the increased TNF-α level in blood circulation. This study investigated the relationship between TNF-α (-857 C/T) polymorphism and OLP patients in an Iranian population.

Methods

Saliva samples were taken from 200 people, including 100 patients with OLP and 100 healthy people who did not have significant differences in age and sex. Then, DNA was extracted from them and the TNF-α (-857 C/T) genotype was identified using the polymerase chain reaction with confronting two-pair primers method. Statistical Package for the Social Sciences version 16 software analyzed the results.

Results

The frequency of C/C, C/T, and T/T genotypes of the TNF-α-857 C/T polymorphism in the patient group were 78%, 18%, and 4%, respectively, and in the control group were 72%, 23%, and 5%, respectively. The differences between the two groups regarding allele (χ 2  =  0.97, p  = 0.32) and genotype (χ 2  =  0.96, p  = 0.62) frequency among the studied population were insignificant.

Conclusion

This study showed that the difference in the frequency of single nucleotide polymorphism TNF-α-857 C/T polymorphism in the patient and control group had no significant relationship with the increased OLP incidence. Also, no significant association was observed between allele and genotype frequency of TNF-α (-857 C/T) with OLP subtypes.

Prognosis of oral epithelial dysplasia in individuals with and without oral lichen planus

OBJECTIVES

To investigate the role of oral lichen planus (OLP) on the long-term prognosis of oral epithelial dysplasia (OED).

METHODS

Retrospective single-centre cohort study using the 2007-2019 database of the Head and Neck Cancer and Oral Medicine units of University College London Hospital. The exposure of interest was the presence of OLP, and the prognostic outcomes included the development of new primary episodes of OED, progression to malignancy and mortality. Cox proportional hazard and Poisson regression models were performed.

RESULTS

A total of 299 patients, of whom 144 had OED arising on the background of OLP (OLP/OED) and 155 had OED without underlying OLP (non-OLP/OED), were included. A pre-existing diagnosis of OLP was significantly associated with a twofold increased risk of subsequent primary OED events (HR = 2.02, p = 0.04), which also developed faster (1.46 vs. 2.96 years, p = 0.04) and with more involvement of non-cancer-prone sites (p = 0.001) than in the non-OLP/OED group. There was no difference between groups in the progression to malignancy or mortality.

CONCLUSIONS

Oral lichen planus/OED patients are at higher risk of multiple episodes of primary OED, which can develop faster and at non-cancer-prone sites as compared to non-OLP/OED individuals. Further research is needed to clarify the effects of OLP upon progression to OSCC and mortality.

Evaluation of the association between TNF-α-1031 T/C polymorphism with oral lichen planus disease

BACKGROUND

Oral lichen planus (OLP) is a T-cell-mediated autoimmune disease that affects the epithelial cells of the oral cavity. This study was performed to investigate any possible relationship between - 1031(T/C) polymorphism (rs1799964) of the tumor necrosis factor α (TNF-α) gene with the risk and severity of oral lichen planus (OLP) disease among an Iranian population.

METHOD

Saliva samples were collected from 100 patients with OLP and a similar number of healthy controls (age and sex-matched). Then, DNA was extracted from the collected samples for genotyping TNF-α-1031 T/C polymorphism using the PCR-CTPP method. The results were assessed using SPSS software.

RESULTS

The findings revealed a significantly higher prevalence of the C allele in OLP patients (53%) compared to healthy controls (36%), suggesting an association between TNF-alpha gene polymorphism and OLP. A multivariate logistic regression analysis supported this finding, as the presence of the C allele was significantly associated with an increased risk of OLP [χ2 = 4.17, p = 0.04, 95% CI = 1.01-2.65, OR = 1.64]. However, our data indicated no significant association between TNF-alpha-1031 T/C gene polymorphism and OLP severity.

CONCLUSIONS

These findings provide the first evidence supporting a possible role of TNF-α-1031 T/C gene polymorphism in OLP susceptibility in the Iranian population. The findings of this study demonstrate a positive association between TNF-α-1031 C/T allele distribution and the risk of OLP disease in the Iranian population. Therefore, carrying the C allele may increase the susceptibility to OLP disease.

An Evidence-Based Update on the Potential for Malignancy of Oral Lichen Planus and Related Conditions: A Systematic Review and Meta-Analysis

A systematic review and a meta-analysis is presented on published articles on the malignant transformation of oral lichen planus (OLP) and related conditions, which, based on current evidence, updates an earlier systematic review published by our research group that included publications until November 2018. In this updated study (Nov-2023) we searched MEDLINE, Embase, Web of Science, and Scopus. We evaluated the methodological quality of studies (QUIPS tool) and carried out meta-analyses. The inclusion criteria were met by 101 studies (38,083 patients), of which, 20 new primary-level studies (11,512 patients) were published in the last 5 years and were added to our updated study. The pooled malignant transformation ratio was 1.43% (95% CI = 1.09-1.80) for OLP; 1.38% (95% CI = 0.16-3.38) for oral lichenoid lesions; 1.20% (95% CI = 0.00-4.25) for lichenoid reactions; and 5.13% (95% CI = 1.90-9.43) for OLP with dysplasia. No significant differences were found between the OLL or LR groups and the OLP subgroup (p = 0.853 and p = 0.328, respectively), and the malignant transformation was significantly higher for the OLP with dysplasia group in comparison with the OLP group (p = 0.001). The factors that had a significant impact with a higher risk of malignant transformation were the presence of epithelial dysplasia, a higher methodological quality, the consumption of tobacco and alcohol, the location of lesions on the tongue, the presence of atrophic and erosive lesions, and infection by the hepatitis C virus. In conclusion, OLP behaves as an oral potentially malignant disorder (OPMD), whose malignancy ratio is probably underestimated as a consequence essentially of the use of inadequate diagnostic criteria and the low methodological quality of the studies on the subject.

Crossroads between Skin and Endocrine Glands: The Interplay of Lichen Planus with Thyroid Anomalies

In this narrative review, we aimed to overview the interplay between lichen planus (LP) and thyroid conditions (TCs) from a dual perspective (dermatologic and endocrine), since a current gap in understanding LP-TC connections is found so far and the topic is still a matter of debate. We searched PubMed from Inception to October 2023 by using the key terms "lichen planus" and "thyroid", (alternatively, "endocrine" or "hormone"). We included original clinical studies in humans according to three sections: LP and TC in terms of dysfunction, autoimmunity, and neoplasia. Six studies confirmed an association between the thyroid dysfunction (exclusively hypothyroidism) and LP/OL (oral LP); of note, only one study addressed cutaneous LP. The sample size of LP/OLP groups varied from 12-14 to 1500 individuals. Hypothyroidism prevalence in OLP was of 30-50%. A higher rate of levothyroxine replacement was identified among OLP patients, at 10% versus 2.5% in controls. The highest OR (odd ratio) of treated hypothyroidism amid OLP was of 2.99 (p < 0.005). Hypothyroidism was confirmed to be associated with a milder OLP phenotype in two studies. A single cohort revealed a similar prevalence of hypothyroidism in LP versus non-LP. Non-confirmatory studies (only on OLP, not cutaneous LP) included five cohorts: a similar prevalence of hypothyroidism among OLP versus controls, and a single cohort showed that the subjects with OLP actually had a lower prevalence of hypothyroidism versus controls (1% versus 4%). Positive autoimmunity in LP/OLP was confirmed in eight studies; the size of the cohorts varied, for instance, with 619 persons with LP and with 76, 92, 105, 108, 192, 247, and 585 patients (a total of 1405) with OLP, respectively; notably, the largest control group was of 10,441 individuals. Four clusters of approaches with respect to the autoimmunity in LP/OLP were found: an analysis of HT/ATD (Hashimoto's thyroiditis/autoimmune thyroid diseases) prevalence; considerations over the specific antibody levels; sex-related features since females are more prone to autoimmunity; and associations (if any) with the clinical aspects of LP/OLP. HT prevalence in OLP versus controls was statistically significantly higher, as follows: 19% versus 5%; 12% versus 6%; and 20% versus 9.8%. A single study addressing LP found a 12% rate of ATDs. One study did not confirm a correlation between OLP-associated clinical elements (and OLP severity) and antibody values against the thyroid, and another showed that positive TPOAb (anti-thyroperoxidase antibodies) was more often found in erosive than non-erosive OLP (68% versus 33%). Just the reverse, one cohort found that OLP subjects had a statistically significantly lower rate of positive TPOAb versus controls (9% versus 15%). Five case-control studies addressed the issue of levothyroxine replacement for prior hypothyroidism in patients that were diagnosed with OLP (no study on LP was identified); three of them confirmed a higher rate of this treatment in OLP (at 8.9%, 9.7%, and 10.6%) versus controls. In conclusion, with regard to LP/OLP-TC, we note several main aspects as practical points for multidisciplinary practitioners: OLP rather than LP requires thyroid awareness; when it comes to the type of thyroid dysfunction, mostly, hypothyroidism should be expected; female patients are more prone to be associated with ATDs; a potential higher ratio of OLP subjects taking levothyroxine was found, thus a good collaboration with an endocrinology team is mandatory; and so far, OLP individuals have not been confirmed to be associated with a higher risk of thyroid nodules/cancer.

Systemic non-steroidal immunomodulators for oral lichen planus treatment-a scoping review

OBJECTIVE

The aim of this scoping review was to evaluate the efficacy and safety of the use of systemic nonsteroidal immunomodulators (SNSI) for oral lichen planus (OLP) treatment.

MATERIALS AND METHODS

This review was conducted according to PRISMA-ScR guidelines and registered at PROSPERO (CRD42021243524). Consulted databases were Pubmed, Embase, Scopus, and Web of Science. The inclusion criteria was as follows: clinical trials, case series, prospective, and retrospective studies conducted with participants presenting OLP of any sex and age.

RESULTS

Thirty-two studies were selected, assessing 9 different SNSI: methotrexate, dapsone, levamisole, hydroxychloroquine, thalidomide, metronidazole, azathioprine, mycophenolate mofetil, and colchicine. Methotrexate and dapsone were the drugs with the best evidence among the options included, regarding number and quality of studies. Methotrexate resulted in significant improvement in the clinical condition and remission of symptoms, ranging between 63 and 93% of cases. Dapsone presented a similar effect to the use of topical corticosteroids and tacrolimus CONCLUSION: Among SNSI therapeutic options, methotrexate, and dapsone showed promising efficacy and safety. However, large-scale randomized clinical trials are still needed.

CLINICAL RELEVANCE

SNSI have been used in the treatment of recalcitrant OLP; however, so far, it is not clear which are the best options. This scoping review highlights the potential use of methotrexate and dapsone.

Contact sensitisation in oral lichen planus: An Australian perspective

BACKGROUND

The role of contact sensitisation in the pathogenesis of oral lichen planus (OLP) has not been clearly defined.

OBJECTIVE

We aimed to evaluate relevant contact sensitisers in OLP.

METHODS

A retrospective study was conducted on OLP patients who underwent patch testing from 1 January 2006 to 31 December 2020 at an Australian tertiary dermatology institution, compared to cheilitis patients patch tested over the same time period.

RESULTS

Ninety-six OLP patients and 152 cheilitis patients were patch tested during the 15-year period. Seventy-one (73.9%) OLP patients and 100 (65.8%) cheilitis patients recorded one or more relevant reactions. Forty-three (44.8%), 22 (22.9%), 21 (21.9%) and 17 (17.7%) OLP patients had relevant reactions to mercury-related chemicals, amalgam, spearmint and carvone, respectively, compared to 6 (3.9%), 3 (2.0%), 4 (2.6%) and 0 (0%) cheilitis patients, respectively (p-value <0.001 each). Four (4.2%) OLP patients had relevant positive reactions to sodium metabisulfite, compared to none in the cheilitis group (p-value 0.021).

CONCLUSION

While dental amalgam is used less frequently these days, we report that mercury (found in amalgam) and additionally spearmint and carvone are relevant sensitisers in OLP in Australia. Sodium metabisulfite may also be a relevant sensitiser in OLP, which has not previously been reported.

Disease severity scoring systems in mucosal lichen planus: A systematic review

Several scoring systems have been developed to evaluate disease severity in mucosal lichen planus, but only a few have been validated to ensure reproducible and accurate assessment of disease severity. The current systematic review was undertaken to identify clinical severity scoring systems in mucosal lichen planus that have undergone validity or reliability testing and to describe their operating characteristics. We performed a bibliographic search in five databases from their inception to October 2022 for severity scoring systems in mucosal lichen planus that have undergone validity or reliability tests. Quality assessment was conducted using the Joanna Briggs Institute Critical Appraisal tools. We have included 118 studies and identified 11 clinical severity scoring systems for oral lichen planus that have undergone validity or reliability testing. Of these, the most reported were the Thongprasom score, the Oral Disease Severity Score (ODSS) and the REU (Reticular/hyperkeratotic, Erosive/erythematous, Ulcerative) scoring systems. We did not identify clinical scoring systems for extraoral mucosal lichen planus that have undergone validity or reliability testing. The ODSS and REU scoring systems have undergone the highest number of validation attempts and reliability assessments for oral lichen planus respectively. However, we have identified numerous factors that have hampered the universal adoption of a standardised scoring system. There is a need for the development and validation of scoring systems for extraoral mucosal lichen planus.

Immune-mediated oral mucosal pathology: a comprehensive review and update for clinicians. Part I

The oral mucosa can be involved in a wide variety of mucocutaneous conditions that may present primarily in the mouth or affect other cutaneous or mucosal sites. Many of these conditions are immune mediated and typically present as inflammatory mucosal pathology. Patients experiencing such conditions usually seek medical evaluation and treatment due to the associated pain and discomfort and occasionally taste disturbance or dysphagia and the overall deterioration in the oral health-related quality of life. These conditions share some common features and there could be some overlapping in their clinical presentation, which can lead to delays in diagnosis and proper management of patients. Clinicians dealing with such disorders, including dermatologists, need to be aware of the oral manifestations of mucocutaneous conditions, their clinical features, underlying mechanisms, diagnostic approaches, and treatment options, as well as the recent advances in the research on these conditions. This review provides a comprehensive, evidence-based reference for clinicians, with updated insights into a group of immune mediated conditions known to cause oral mucosal pathology. Part one will cover oral lichen planus, erythema multiforme and systemic lupus erythematosus, while part two will cover pemphigus vulgaris and mucous membrane pemphigoid, recurrent aphthous stomatitis, in addition to the less common disorders linear IgA disease, dermatitis herpetiformis and epidermolysis bullosa.

Evaluation of the salivary level of glutathione reductase, catalase and free thiol in patients with oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) is a usual chronic inflammatory disease of the oral mucosa with malignant capacity, whose pathogenesis is not yet well known. Free radicals and reactive oxygen species may have a vital role in the pathogenesis of oral lichen planus. This study aimed to assess Glutathione reductase, catalase, and free thiol levels in the saliva of OLP patients and compare it with healthy people.

METHODS

In this cross-sectional study, 35 patients with OLP and 20 healthy people were involved. Five mL of whole, unstimulated saliva samples were collected in the morning, and the salivary levels of antioxidants were measured by ELISA technique. In this experiment, sex, age and OLP types were also evaluated.

RESULTS

There was a significant decrease in the patients' salivary level of Glutathione reductase (0.2043 mU/ml in patients and 0.3901 mU/ml in the control group) and catalase (0.1525 mU/ml in patients and 0.2700 mU/ml in the control group) (p = 0.001). But there were no differences between the two groups regarding free-thiol levels (0.0586 mU/ml in patients and 0.0569 mU/ml in the control group) (p = 0.7). However, there was no correlation between age and gender with the antioxidants' contents. There was a significant decrease in glutathione reductase and catalase in the erosive type than in the non-erosive type.

CONCLUSIONS

In this study, we found that the salivary levels of Glutathione reductase and Catalase were lower in OLP patients than in the healthy group, which means these antioxidants were affected by OLP and also associated with the type of it. So salivary Glutathione reductase and Catalase levels may be used as biomarkers for OLP monitoring and treatment.

Association of interleukin-8 polymorphism (+ 781 C/T) with the risk of oral Lichen Planus disease

BACKGROUND

Oral Lichen Planus (OLP) is a chronic inflammatory mucosal disease. The pathogenesis of OLP is unknown. The Single Nucleotide Polymorphism (SNP) that occurs in the regulatory position + 781 could affect the expression of interleukin-8. This polymorphism is probably associated with increased serum levels of IL-8. The current study aimed to investigate the genotype and allele frequencies of IL-8( + 781 C/T) in OLP patients and whether it is associated with the severity of OLP disease in an Iranian population.

METHODS

Three milliliters of saliva were taken from 100 patients with OLP and 100 healthy individuals who were matched in age and gender. After DNA extraction from saliva samples of patients and healthy individuals, the genotype of IL-8 at position + 781 is detected using the PCR-RFLP method. The results were analyzed using SPSS software.

RESULTS

Frequency of C/C, T/C, and T/T genotypes at position IL-8 + 781 gene in the patient group were 47%, 41%, and 12%, respectively, and in the control group, were 37%, 42%, and 21%. The difference between the two groups regarding allele frequency distribution was statistically significant (χ² = 3.86, p = 0.049, 95% CI = 0.44-1, OR = 0.66). Our results indicated the significantly higher frequency of the TT genotype in the erosive OLP compared to the nonerosive group (p = 0.03, OR = 0.89, 95% CI = 0.49-1.6).

CONCLUSION

This study depicted the difference in the frequency of SNP IL-8 + 781 C/T allele in the patient and control groups had a significant association with the risk of OLP. In addition, our data revealed that IL-8 + 781 C/T polymorphisms might be associated with the severity of OLP in the Iranian population.

Tough Adhesive Hydrogel for Intraoral Adhesion and Drug Delivery

Oral lichen planus (OLP) and recurrent aphthous stomatitis (RAS) are common chronic inflammatory conditions, manifesting as painful oral lesions that negatively affect patients' quality of life. Current treatment approaches are mainly palliative and often ineffective due to inadequate contact time of the therapeutic agent with the lesions. Here, we developed the Dental Tough Adhesive (DenTAl), a bioinspired adhesive patch with robust mechanical properties, capable of strong adhesion against diverse wet and dynamically moving intraoral tissues, and extended drug delivery of clobetasol-17-propionate, a first-line drug for treating OLP and RAS. DenTAl was found to have superior physical and adhesive properties compared to existing oral technologies, with ~2 to 100× adhesion to porcine keratinized gingiva and ~3 to 15× stretchability. Clobetasol-17-propionate incorporated into the DenTAl was released in a tunable sustained manner for at least 3 wk and demonstrated immunomodulatory capabilities in vitro, evidenced by reductions in several cytokines, including TNF-α, IL-6, IL-10, MCP-5, MIP-2, and TIMP-1. Our findings suggest that DenTAl may be a promising device for intraoral delivery of small-molecule drugs applicable to the management of painful oral lesions associated with chronic inflammatory conditions.

Emerging potential of phototherapy in management of symptomatic oral lichen planus: A systematic review of randomised controlled clinical trials

Phototherapy incorporating photobiomodulation therapy and antimicrobial photodynamic therapy has been utilised as antioxidants in symptomatic oral lichen planus (OLP) management; however, its role of intervention remains controversial. The aim of this systematic review of CRD42021227788 PROSPERO (an international prospective register of systematic reviews in health and social care) registration number was to oversee and determine phototherapy efficacy in patients with symptomatic OLP, identifying and bridging the literature gaps by proposing recommendations for future studies. A search strategy was developed in consistent with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Various electronic databases were exercised to search for randomised controlled clinical trials (RCTs). Several search engines were employed to analyse a total of 177 studies of which nine included. A wide range of utilised laser and light-emitted diode wavelengths between 630 and 808 nm and irradiance ranged between 10 and 13 mW/cm² were noted. 67% of studies reported a high risk of bias and a high heterogeneity obtained from numerical data for quantitative analysis, therefore meta-analysis was impossible to conduct. Despite inconsistency and diversity in phototherapy parameters, treatment protocols, photosensitiser (type, concentration and method of application) and outcome assessment tools, the majority of the studies showed positive results compared with standard care treatments. Hence, a necessity to perform well-designed RCTs with robust methodology is warranted, after acknowledging the current drawbacks and addressing the suggested recommendations highlighted in our review. Moreover, advanced knowledge in understanding further phototherapy-antioxidants molecular mechanistic in symptomatic OLP is required.

The paradigm of miRNA and siRNA influence in Oral-biome

Short nucleotide sequences like miRNA and siRNA have attracted a lot of interest in Oral-biome investigations. miRNA is a small class of non-coding RNA that regulates gene expression to provide effective regulation of post-transcription. On contrary, siRNA is 21-25 nucleotide dsRNA impairing gene function post-transcriptionally through inhibition of mRNA for homologous dependent gene silencing. This review highlights the application of miRNA in oral biome including oral cancer, dental implants, periodontal diseases, gingival fibroblasts, oral submucous fibrosis, radiation-induced oral mucositis, dental Pulp, and oral lichenoid disease. Moreover, we have also discussed the application of siRNA against the aforementioned disease along with the impact of miRNA and siRNA to the various pathways and molecular effectors pertaining to the dental diseases. The influence of upregulation and downregulation of molecular effector post-treatment with miRNA and siRNA and their impact on the clinical setting has been elucidated. Thus, the mentioned details on application of miRNA and siRNA will provide a novel gateway to the scholars to not only mitigate the long-lasting issue in dentistry but also develop new theragnostic approaches.

Efficacy of Topical Treatments for the Management of Symptomatic Oral Lichen Planus: A Systematic Review

Oral lichen planus (OLP) is a chronic mucosal inflammatory disease associated with T-cell-mediated immunological dysfunction. Symptomatic OLP is a painful condition, and complete healing is often not achieved. The aim of this systematic review was to assess the effectiveness of topical drugs, medications, and other interventions compared to placebo or to other treatments in pain reduction and clinical resolution in adult patients with symptomatic OLP. A detailed electronic literature search was performed through the MEDLINE (PubMed) database between 1 January 2005 and 30 September 2022. Eligible studies were selected based on the inclusion criteria, and a quality assessment was conducted. From 649 titles, 121 articles were selected as abstracts, 75 papers were assessed as full text, along with 15 other papers obtained through a manual search. A total of 15 RCTs were finally included in the review process. Because of the significant heterogeneity in the study design of the included studies, no meta-analysis of the data could be performed. Topical corticosteroids represent the first-line treatment in the management of symptomatic OLP due to their efficacy and minimal adverse effects. Calcineurin inhibitors seem to be equally effective and are indicated in recalcitrant cases, extensive lesions, patients susceptible to oral candidiasis, or cases unresponsive to corticosteroids. Other treatments, such as aloe vera, chamomile, isotretinoin, ozone, and laser therapy, could be beneficial as adjunct therapies in association with first-line treatments.

Chronic Ulcerative Stomatitis (CUS) as an Interdisciplinary Diagnostic Challenge: A Literature Review

Chronic ulcerative stomatitis (CUS) is a rarely reported disease affecting the oral cavity, most often affecting middle-aged Caucasian females. The aim of the present study is to present the diagnosis, differentiation, and interdisciplinary treatment of this rare disease. CUS is characterized by the presence of an oral erosive or ulcerative lesion. The autoimmune pathogenesis of CUS includes affecting the antigen's activity by DNA-breaking and protein-hydrolyzing enzymes. The stratified epithelium-specific antinuclear antibodies (SES-ANA) are associated with CUS development. Clinically, the lesions presented in oral mucosa might resemble an erosive form of oral lichen planus, whereas gingival lesions seem to be similar to desquamative gingivitis related to dermatological diseases manifested in the oral cavity. Patients often report subjective symptoms related to oral mucosa and general symptoms. Histopathological presentation of CUS is often non-specific and includes sub-epithelial separation from underlying connective tissue, atrophic epithelium, and inflammatory infiltrate with an increased number of plasma cells and lymphocytes. Direct immunofluorescence (DIF) might be used in CUS diagnostics. CUS generally remains nonsusceptible to corticosteroid treatments; however, antimalarial drugs and calcineurin inhibitors are more effective. Further research should be conducted in order to implement a diagnostic protocol and observe the long-term results of CUS management.

Paeoniflorin drives the immunomodulatory effects of mesenchymal stem cells by regulating Th1/Th2 cytokines in oral lichen planus

Lichen planus (LP) is a chronic inflammatory disease. Oral lichen planus (OLP) mainly appears as oral mucosal reticular or ulcerative lesions with an unknown etiology. We aimed to explore the immunomodulatory effect of paeoniflorin (PF) in mesenchymal stem cells (MSCs) and the potential involvement of Th1/Th2 cytokines in OLP. The effects of paeoniflorin on the proliferation and migration of MSCs were detected by Cell Counting Kit-8 (CCK8) and Transwell assays. MSCs were subjected to osteogenic, adipogenic and neurogenic induction followed by Alizarin red, oil red O, real-time PCR and immunofluorescence assays. We found that paeoniflorin promoted the proliferation, migration and multilineage differentiation of MSCs from OLP lesions (OLP-MSCs) in vitro. Paeoniflorin pretreatment increased the inhibitory effect of OLP-MSCs on peripheral blood mononuclear cells. Furthermore, paeoniflorin-pretreated OLP-MSCs simultaneously decreased Th1 cytokine levels and increased Th2 cytokine levels in T lymphocyte cocultures. Finally, paeoniflorin-pretreated OLP-MSCs also promoted the Th1/Th2 balance both in vitro and in the serum of mice that received skin allografts. In conclusion, paeoniflorin enhanced MSC immunomodulation and changed the inflammatory microenvironment via T lymphocytes, suggesting that the improvement of OLP-MSCs is a promising therapeutic approach for OLP.

Demographics, Clinicopathological Profile of Oral Lichen Planus of South Kerala Population: A Cross-Sectional Study

Background: Oral lichen planus (OLP) is a chronic mucocutaneous inflammatory lesion of unknown cause. The buccal mucosa is the most frequently affected anatomic site and the lesion is bilateral. The objective of this retrospective study was to investigate the epidemiological and clinical characteristics of 250 OLP patients in South Kerala. This was done by figuring out these patients’ epidemiological and clinical characteristics.

Materials and methods: In the present study, patients who reported between September 2018 and December 2021 were selected employing the diagnostic criteria consistent with the WHO classification of OLP. Data of all the patient’s characteristic features were collected and evaluated using the Statistical Package for the Social Sciences (SPSS) software for statistical analysis.

Results: Out of 250 patients, 52% were females and 48% were males. Reticular (n = 145, 58%) and erosive forms (n = 105, 42%) were the two clinical presentations of the lesions that were most consistently observed. The age group of 25-34 years reported the highest number of cases (n = 71, 28.4%). According to the chi-square test, there were statistically highly significant differences between the hyperpigmentation, age, and type of OLP. While 43.2% (n = 108) of cases reported a burning sensation, pain, or soreness, 56.8% (n = 142) of cases were asymptomatic. There were statistically significant differences between the type of OLP and the reported symptoms (p = 0.001). Mild to moderate dysplastic changes were documented in 5.6% during the follow-up period. A successful treatment outcome with topical steroid administration was recorded in the study sample.

Conclusion: It was apparent that patients typically have bilateral lesions involving the buccal and labial mucosa, manifesting with varying degrees of oral discomfort. Although patients frequently have more than one variant of OLP, the lesions are typically reticular or erosive in nature. A meticulous follow-up is crucial to determine its malignant change.

Electrospun patch delivery of anti-TNFα F(ab) for the treatment of inflammatory oral mucosal disease

Chronic ulcerative oral mucosal inflammatory diseases, including oral lichen planus and recurrent aphthous stomatitis, are painful and highly prevalent, yet lack effective clinical management. In recent years, systemic biologic therapies, including monoclonal antibodies that block the activity of cytokines, have been increasingly used to treat a range of immune-mediated inflammatory conditions such as rheumatoid arthritis and psoriasis. The ability to deliver similar therapeutic agents locally to the oral epithelium could radically alter treatment options for oral mucosal inflammatory diseases, where pro-inflammatory cytokines, in particular tumour-necrosis factor-α (TNFα), are major drivers of pathogenesis. To address this, an electrospun dual-layer mucoadhesive patch comprising medical-grade polymers was investigated for the delivery of F(ab) biologics to the oral mucosa. A fluorescent-labelled F(ab) was incorporated into mucoadhesive membranes using electrospinning with 97% v/v ethanol as a solvent. The F(ab) was detected within the fibres in aggregates when visualised by confocal microscopy. Biotinylated F(ab) was rapidly eluted from the patch (97 ± 5% released within 3 h) without loss of antigen-binding activity. Patches applied to oral epithelium models successfully delivered the F(ab), with fluorescent F(ab) observed within the tissue and 5.1 ± 1.5% cumulative transepithelial permeation reached after 9 h. Neutralising anti-TNFα F(ab) fragments were generated from whole IgG by papain cleavage, as confirmed by SDS-PAGE, then incorporated into patches. F(ab)-containing patches had TNFα neutralising activity, as shown by the suppression of TNFα-mediated CXCL8 release from oral keratinocytes cultured as monolayers. Patches were applied to lipopolysaccharide-stimulated immune-competent oral mucosal ulcer equivalents that contained primary macrophages. Anti-TNFα patch treatment led to reduced levels of active TNFα along with a reduction in the levels of disease-implicated T-cell chemokines (CCL3, CCL5, and CXCL10) to baseline concentrations. This is the first report of an effective device for the delivery of antibody-based biologics to the oral mucosa, enabling the future development of new therapeutic strategies to treat painful conditions.

Differential genotypes of TNF-α and IL-10 for immunological diagnosis in discoid lupus erythematosus and oral lichen planus: A narrative review

Discoid lupus erythematosus and oral lichen planus are chronic systemic immune system-mediated diseases with unclear etiology and pathogenesis. The oral mucosa is the common primary site of pathogenesis in both, whereby innate and adaptive immunity and inflammation play crucial roles. The clinical manifestations of discoid lupus erythematosus on the oral mucosa are very similar to those of oral lichen planus; therefore, its oral lesion is classified under oral lichenoid lesions. In practice, the differential diagnosis of discoid lupus erythematosus and oral lichen planus has always relied on the clinical manifestations, with histopathological examination as an auxiliary diagnostic tool. However, the close resemblance of the clinical manifestations and histopathology proves challenging for accurate differential diagnosis and further treatment. In most cases, dentists and pathologists fail to distinguish between the conditions during the early stages of the lesions. It should be noted that both are considered to be precancerous conditions, highlighting the significance of early diagnosis and treatment. In the context of unknown etiology and pathogenesis, we suggest a serological and genetic diagnostic method based on TNF-α and IL-10. These are the two most common cytokines produced by the innate and adaptive immune systems and they play a fundamental role in maintaining immune homeostasis and modulating inflammation. The prominent variability in their expression levels and gene polymorphism typing in different lesions compensates for the low specificity of current conventional diagnostic protocols. This new diagnostic scheme, starting from the immunity and inflammation of the oral mucosa, enables simultaneous comparison of discoid lupus erythematosus and oral lichen planus. With relevant supportive evidence, this information can enhance physicians’ understanding of the two diseases, contribute to precision medicine, and aid in prevention of precancerous conditions.

Intravital longitudinal cellular visualization of oral mucosa in a murine model based on rotatory side-view confocal endomicroscopy

Oral mucosa is a soft tissue lining the inside of the mouth, protecting the oral cavity from microbiological insults. The mucosal immune system is composed of diverse types of cells that defend against a wide range of pathogens. The pathophysiology of various oral mucosal diseases has been studied mostly by ex vivo histological analysis of harvested specimens. However, to analyze dynamic cellular processes in the oral mucosa, longitudinal in vivo observation of the oral mucosa in a single mouse during pathogenesis is a highly desirable and efficient approach. Herein, by utilizing micro GRIN lens-based rotatory side-view confocal endomicroscopy, we demonstrated non-invasive longitudinal cellular-level in vivo imaging of the oral mucosa, visualizing fluorescently labeled cells including various immune cells, pericytes, nerve cells, and lymphatic and vascular endothelial cells. With rotational and sliding movement of the side-view endomicroscope on the oral mucosa, we successfully achieved a multi-color wide-area cellular-level visualization in a noninvasive manner. By using a transgenic mouse expressing photoconvertible protein, Kaede, we achieved longitudinal repetitive imaging of the same microscopic area in the buccal mucosa of a single mouse for up to 10 days. Finally, we performed longitudinal intravital visualization of the oral mucosa in a DNFB-derived oral contact allergy mouse model, which revealed highly dynamic spatiotemporal changes of CSF1R or LysM expressing immune cells such as monocytes, macrophages, and granulocytes in response to allergic challenge for one week. This technique can be a useful tool to investigate the complex pathophysiology of oral mucosal diseases.

The Functional Mechanism of MicroRNA in Oral Lichen Planus

Non-coding RNAs (ncRNAs) are transcribed from the genomes of mammals and other complex organisms, and many of them are alternately spliced and processed into smaller products. Types of ncRNAs include microRNAs (miRNAs), circular RNAs, and long ncRNAs. miRNAs are about 21 nucleotides long and form a broad class of post-transcriptional regulators of gene expression that affect numerous developmental and physiological processes in eukaryotes. They usually act as negative regulators of mRNA expression through complementary binding sequences in the 3’-UTR of the target mRNA, leading to translation inhibition and target degradation. In recent years, the importance of ncRNA in oral lichen planus (OLP), particularly miRNA, has attracted extensive attention. However, the biological functions of miRNAs and their mechanisms in OLP are still unclear. In this review, we discuss the role and function of miRNAs in OLP, and we also describe their potential functional roles as biomarkers for the diagnosis of OLP. MiRNAs are promising new therapeutic targets, but more work is needed to understand their biological functions.

Automatic Detection of Image-Based Features for Immunosuppressive Therapy Response Prediction in Oral Lichen Planus

Oral lichen planus (OLP) is a chronic inflammatory disease, and the common management focuses on controlling inflammation with immunosuppressive therapy. While the response to the immunosuppressive therapy is heterogeneous, exploring the mechanism and prediction of the response gain greater importance. Here, we developed a workflow for prediction of immunosuppressive therapy response prediction in OLP, which could automatically acquire image-based features. First, 38 features were acquired from 208 OLP pathological images, and 6 features were subsequently obtained which had a significant impact on the effect of OLP immunosuppressive therapy. By observing microscopic structure and integrated with the corresponding transcriptome, the biological implications of the 6 features were uncovered. Though the pathway enrichment analysis, three image-based features which advantageous to therapy indicated the different lymphocytes infiltration, and the other three image-based features which bad for therapy respectively indicated the nicotinamide adenine dinucleotide (NADH) metabolic pathway, response to potassium ion pathway and adenosine monophosphate (AMP) activated protein kinase pathway. In addition, prediction models for the response to immunosuppressive therapy, were constructed with above image-based features. The best performance prediction model built by logistic regression showed an accuracy of 90% and the area under the receiver operating characteristic curve (AUROC) reached 0.947. This study provided a novel approach to automatically obtain biological meaningful image-based features from unannotated pathological images, which could indicate the immunosuppressive therapy in OLP. Besides, the novel and accurate prediction model may be useful for the OLP clinical management.

The efficacy of henna (Lawsonia inermis L.) mouthwash versus chlorhexidine gluconate 0.2% mouthwash as adjuvant therapy of oral lichen planus: A randomized double-blind clinical trial

ETHNOPHARMACOLOGICAL RELEVANCE

In modern medicine, some traditional remedies are introduced to be effective in treatment. Accordingly, the henna plant (Lawsonia inermis L.) is studied more than before. Previous studies have shown many medical properties for henna, such as anti-inflammatory and anti-fungal properties.

AIM OF THE STUDY

Oral lichen planus (OLP) is a common mucocutaneous disease with chronic immunomodulatory disruptions. Topical corticosteroids are the first line of OLP treatment. Previous studies have suggested different adjunctive therapies for preventing the side effects of corticosteroids overuse. This study aimed to compare the effects of henna and chlorhexidine mouthwashes as adjunctive therapy.

MATERIALS AND METHODS

This parallel-group, double-blind, randomized controlled study was conducted on forty OLP patients. Luteolin content was determined in Henna mouthwash composed of 2% aqueous extract of henna, 2% ethanol, 10% glycerol, and 0.1% methylparaben distilled water. Henna or chlorhexidine mouthwashes were prescribed twice daily as an adjuvant to the topical corticosteroid treatment. Visual analog scale (VAS) index and Thongprasom rating were used to measure pain intensity and clinical signs of patients at days 0,7, and 14. The collected data were analyzed using SPSS software (version 26.0; SPSS). Ordinal logistic regression was used to investigate the effect of independent variables on Thongprasom and VAS scores.

RESULTS

In this clinical trial, 82.6% of the participants were women. There was no difference between the two study groups in terms of VAS scores (p = 0.404) and clinical features (p = 0.305) in the second follow-up visit. All drug regimens caused clinical signs and symptoms relief.

CONCLUSIONS

There was no significant difference between the groups receiving topical corticosteroid supplementation, neither henna mouthwash nor chlorhexidine mouthwash. The therapeutic effects of henna mouthwash in the main or adjuvant treatment of OLP need more evaluation in future research. Henna mouthwash can be a good alternative to chlorhexidine mouthwash if no side effects are reported.

Where do you live? North versus Central-South differences in relation to Italian patients with oral lichen planus: a cross-sectional study from the SIPMO (Italian Society of Oral Pathology and Medicine)

BACKGROUND

Oral lichen planus (OLP) is an immune-mediated inflammatory chronic disease of the oral mucosa, with different patterns of clinical manifestations which range from keratotic manifestations (K-OLP) to predominantly non-keratotic lesions (nK-OLP). The aim of the study was to analyze the differences in the clinical, psychological profile and symptoms between Italian patients of the North and Central-South with K-OLP and nK-OLP.

METHODS

270 K-OLP and 270 nK-OLP patients were recruited in 15 Italian universities. The Numeric Rating Scale (NRS), Total Pain Rating Index (T-PRI), Hamilton Rating Scales for Depression and for Anxiety (HAM-D and HAM-A), Pittsburgh Sleep Quality Index (PSQI), and Epworth Sleepiness Scale (ESS) were administered.

RESULTS

The Central-South K-OLP (CS-K-OLP) patients reported a higher frequency of pain/burning compared with the K-OLP patients of the North (N-K-OLP) with higher scores in the NRS and T-PRI (p value < 0.001**). The CS-K-OLP and the CS-nK-OLP patients showed higher scores in the HAM-D, HAM-A, PSQI and ESS compared with the Northern patients (p value < 0.001**). Multivariate logistic regression revealed that the NRS and T-PRI showed the greatest increase in the R2 value for the CS-K-OLP (DR2 = 9.6%; p value < 0.001**; DR2 = 9.7% p value < 0.001**; respectively) and that the oral symptoms (globus, itching and intraoral foreign body sensation) and PSQI showed the greatest increase in the R2 value for the CS-nK-OLP (DR2 = 5.6%; p value < 0.001**; DR2 = 4.5% p value < 0.001** respectively).

CONCLUSIONS

Pain and mood disorders are predominant in patients with OLP in the Central-South of Italy. Clinicians should consider that the geographical living area may explain the differences in oral symptoms and psychological profile in OLP.

Childhood oral lichen planus: a case series with review of literature

BACKGROUND

Oral Lichen Planus (OLP) is a chronic autoimmune mucocutaneous condition, the exact etiology of which is still unknown. It is known to occur chiefly in adults and has a reported prevalence of 0.5-2% in general population and < 2-3% of total in pediatric population. OLP is considered as Oral Potentially Malignant Disorder with a malignant transformation rate of 1-2% in adults. Its occurrence in children is a rare finding with few cases reported in the literature. As a result, it gets misdiagnosed by the general practitioner and hence, there is a need to consider OLP in differential diagnosis of white lesions of oral cavity even in children. Therefore, in this paper, we present six cases of childhood OLP along with their management and follow-up.

CASE SERIES

We present here six patients aged between 11 and 13 years who presented either as incidental finding or as symptomatic lesions and were diagnosed with OLP. Symptomatic patients were treated with topical steroid ointment and both the symptomatic and asymptomatic patients were followed-up. We have also presented literature review of childhood OLP reported in PubMed, Medline and google scholar from 1980 till December 2020.

CONCLUSION

OLP is unusual in children and is often left untreated due to low awareness among the patients. Can be often misdiagnosed and should be considered in differential diagnosis of any white lesion of oral cavity. Any such lesions must be correctly diagnosed in time to institute appropriate management and follow-up.

Immune mechanisms in oral lichen planus

Oral lichen planus (OLP) is a T-cell-mediated inflammatory disease of the oral mucosa that has been extensively researched over many years but as yet the mechanisms of pathogenesis are still not fully understood. Whilst the specific etiologic factors driving OLP remain ambiguous, evidence points to the development of a chronic, dysregulated immune response to OLP-mediating antigens presented by innate immune cells and oral keratinocytes leading to increased cytokine, chemokine and adhesion molecule expression. These molecules recruit T-cells and mast cells to the diseased site and orchestrate a complex interplay between cells that culminates in keratinocyte cell death, mucosal basement membrane destruction and long-term chronicity of the disease. The main lymphocytes involved are thought to be CD8+ cytotoxic and CD4+ Th1 polarised T-cells although recent evidence indicates the involvement of other Th subsets such as Th9, Th17 and Tregs, suggesting that a more complex immune cell relationship exists during the disease process. This review provides an overview of the immune mechanisms at play in OLP pathogenesis with particular emphasis on the role of the different Th subsets and how these recent discoveries may guide research toward identifying potential therapeutic targets.

Oral Health and Liver Disease: Bidirectional Associations—A Narrative Review

Several links between chronic liver disease and oral health have been described and are discussed in this narrative review. Oral manifestations such as lichen planus, ulcers, xerostomia, erosion and tongue abnormalities seem to be particularly prevalent among patients with chronic liver disease. These may be causal, coincidental, secondary to therapeutic interventions, or attributable to other factors commonly observed in liver disease patients. In addition, findings from both experimental and epidemiological studies suggest that periodontitis can induce liver injury and contribute to the progression of chronic liver disease through periodontitis-induced systemic inflammation, endotoxemia, and gut dysbiosis with increased intestinal translocation. This has brought forward the hypothesis of an oral-gut-liver axis. Preliminary clinical intervention studies indicate that local periodontal treatments may lead to beneficial liver effects, but more human studies are needed to clarify if treatment of periodontitis truly can halt or reverse progression of liver disease and improve liver-related outcomes.

PCR-based evaluation of human papillomavirus genotypes in oral lichen planus

Objective:

The objective of the study was to use polymerase chain reaction (PCR) to examine and compare the genotype distribution of human papillomavirus (HPV) in oral lichen planus (OLP).

Materials and Methods:

Deoxyribonucleic acid (DNA) was extracted from 20 OLP biopsy specimens. Conventional PCR assay employing consensus HPV primers was used to identify HPV DNA. Positive PCR samples were then subjected to PCR assay with HPV type-specific primers.

Results:

Out of the total 20 OLP specimens evaluated, eight samples (40%) were positive for HPV. Females had a 41.7% higher HPV-positive rate than males. The most common type in the HPV type-specific PCR assay was HPV-18 (75%), which is a high-risk type of HPV linked to malignant diseases. The erosive kind of OLP had the greatest percentage of HPV positives (50%).

Conclusion:

The present study confirms the detection of HPV in OLP lesions, as determined by PCR-coupled HPV gene sequencing, as well as its likely mechanism of malignant transformation.

Applications of Novel and Nanostructured Drug Delivery Systems for the Treatment of Oral Cavity Diseases

PURPOSE

Novel drug delivery systems (DDSs) hold great promise for the treatment of oral cavity diseases. The main objective of this article was to provide a detailed overview regarding recent advances in the use of novel and nanostructured DDSs in alleviating and treating unpleasant conditions of the oral cavity. Strategies to maximize the benefits of these systems in the treatment of oral conditions and future directions to overcome these issues are also discussed.

METHODS

Publications from the last 10 years investigating novel and nanostructured DDSs for pathologic oral conditions were browsed in a systematic search using the PubMed/MEDLINE, Web of Science, and Scopus databases. Research on applications of novel DDSs for periodontitis, oral carcinomas, oral candidiasis, xerostomia, lichen planus, aphthous stomatitis, and oral mucositis is summarized. A narrative exploratory review of the most recent literature was undertaken.

FINDINGS

Conventional systemic administration of therapeutic agents could exhibit high clearance of drugs from the bloodstream and low accumulation at the target site. In contrast, conventional topical systems face problems such as short residence time in the affected region and low patient compliance. Novel and nanostructured DDSs are among the most effective and commonly used methods for overcoming the problems of conventional DDSs. The main advantages of these systems are that they possess the ability to protect active agents from systemic and local clearance, enhance bioavailability and cellular uptake, and provide immediate or modified release of therapeutic agents after administration. In the design of local drug delivery devices such as nanofiber mats, films, and patches, components and excipients can significantly affect factors such as drug release rate, residence time in the oral cavity, and taste in the mouth. Choosing appropriate additives is therefore essential.

IMPLICATIONS

Local drug delivery devices such as nanofiber mats, nanoparticles, liposomes, hydrogels, films, and patches for oral conditions can significantly affect drug efficacy and safety. However, more precise clinical studies should be designed and conducted to confirm promising in vitro and in vivo results. In recent years, novel and nanostructured DDSs increasingly attracted the attention of researchers as a means of treatment and alleviation of oral diseases and unpleasant conditions. However, more clinical studies should be performed to confirm promising in vitro and in vivo results. To transform a successful laboratory model into a marketable product, the long-term stability of prepared formulations is essential. Also, proper scale-up methods with optimum preparation costs should be addressed.

Metabolomics and Transcriptomics Analysis on Metabolic Characteristics of Oral Lichen Planus

Objective

To explore metabolic biomarkers related to erosive and reticulated oral lichen planus (OLP) by non-targeted metabolomics methods and correlate metabolites with gene expression, and to investigate the pathological network pathways of OLP from the perspective of metabolism.

Methods

A total of 153 individuals were enrolled in this study, including 50 patients with erosive oral lichen planus (EOLP), 51 patients with reticulated oral lichen planus (ROLP), and 52 healthy controls (HC). The ultra-high-performance liquid chromatography quadrupole-Orbitrap high-resolution accurate mass spectrometry (UHPLC/Q-Orbitrap HRMS) was used to analyze the metabolites of 40 EOLP, 40 ROLP, and 40 HC samples, and the differential metabolic biomarkers were screened and identified. The regulatory genes were further screened through the shared metabolites between EOLP and ROLP, and cross-correlated with the OLP-related differential genes in the network database. A “gene-metabolite” network was constructed after finding the key differential genes. Finally, the diagnostic efficiency of the biomarkers was verified in the validation set and a diagnostic model was constructed.

Result

Compared with HC group, a total of 19 and 25 differential metabolites were identified in the EOLP group and the ROLP group, respectively. A total of 14 different metabolites were identified between EOLP and ROLP. Two diagnostic models were constructed based on these differential metabolites. There are 14 differential metabolites shared by EOLP and ROLP. The transcriptomics data showed 756 differentially expressed genes, and the final crossover network showed that 19 differential genes were associated with 12 metabolites. Enrichment analysis showed that alanine, aspartate and glutamate metabolism were closely associated with the pathogenesis of OLP.

Conclusion

The metabolic change of different types of OLP were clarified. The potential gene perturbation of OLP was provided. This study provided a strong support for further exploration of the pathogenic mechanism of OLP.

Efficacy of topical non-steroidal immunomodulators in the treatment of oral lichen planus: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review was to assess the efficacy and safety of topical non-steroidal immunomodulators (TNSIs) for oral lichen planus (OLP) treatment.

MATERIALS AND METHODS

A search strategy designed for this purpose retrieved 1156 references. After analysis of titles and abstracts, 75 studies were selected for full-text analysis. Only randomized controlled clinical trials were selected, resulting in 28 studies included for qualitative and quantitative analysis.

RESULTS

The meta-analysis showed similar benefits in clinical response and symptom resolution between tacrolimus 0.1% and pimecrolimus 1% in comparison to topical steroids (TS). Pimecrolimus showed superior efficacy of clinical response but not for symptom resolution compared to placebo. Tacrolimus and pimecrolimus showed better performance preventing symptom relapse, while pimecrolimus also prevented clinical relapse better than TS. Cyclosporine was superior to placebo; however, TS showed better efficacy of clinical response. Thalidomide and retinoid were assessed in only one trial each, and both showed similar efficacy to TS. Rapamycin also presented similar clinical response to TS; however, the later showed greater reduction of symptoms. Mycophenolate mofetil 2% mucoadhesive was no better than placebo. No serious adverse effects have been reported. Cyclosporine showed a higher frequency and variety of adverse effects.

CONCLUSIONS

Topical tacrolimus and pimecrolimus are safe and effective alternatives for OLP treatment.

CLINICAL RELEVANCE

TS are usually the first choice for OLP treatment. Because some oral lesions may have a low response to treatment with TS, more topical therapeutic options, such as TNSIs, should be considered before systemic steroids are used.

Efficacy of topical non-steroidal immunomodulators in the treatment of oral lichen planus: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review was to assess the efficacy and safety of topical non-steroidal immunomodulators (TNSIs) for oral lichen planus (OLP) treatment.

MATERIALS AND METHODS

A search strategy designed for this purpose retrieved 1156 references. After analysis of titles and abstracts, 75 studies were selected for full-text analysis. Only randomized controlled clinical trials were selected, resulting in 28 studies included for qualitative and quantitative analysis.

RESULTS

The meta-analysis showed similar benefits in clinical response and symptom resolution between tacrolimus 0.1% and pimecrolimus 1% in comparison to topical steroids (TS). Pimecrolimus showed superior efficacy of clinical response but not for symptom resolution compared to placebo. Tacrolimus and pimecrolimus showed better performance preventing symptom relapse, while pimecrolimus also prevented clinical relapse better than TS. Cyclosporine was superior to placebo; however, TS showed better efficacy of clinical response. Thalidomide and retinoid were assessed in only one trial each, and both showed similar efficacy to TS. Rapamycin also presented similar clinical response to TS; however, the later showed greater reduction of symptoms. Mycophenolate mofetil 2% mucoadhesive was no better than placebo. No serious adverse effects have been reported. Cyclosporine showed a higher frequency and variety of adverse effects.

CONCLUSIONS

Topical tacrolimus and pimecrolimus are safe and effective alternatives for OLP treatment.

CLINICAL RELEVANCE

TS are usually the first choice for OLP treatment. Because some oral lesions may have a low response to treatment with TS, more topical therapeutic options, such as TNSIs, should be considered before systemic steroids are used.

Analysis of the psychopathological profile, quality of life, and cost-effectiveness of oral lichen planus patients treated with photobiomodulation

OBJECTIVES

To evaluate the effect of PBM on the psychological profile and quality of life of patients with oral lichen planus (OLP) in comparison to corticoid and to investigate the cost-effectiveness of both treatments.

MATERIALS AND METHODS

Patients were randomized into two groups: Control (clobetasol propionate 0.05%) and Photobiomodulation (660 nm, 100mW, 177 J/cm², 5 s, 0.5 J) twice a week for 30 days. The Hospital Anxiety and Depression Scale (HADS) and OHIP-14 were used in different treatment time points and at follow-up. The cost-effectiveness was calculated using the improvement in OHIP-14 after treatment.

RESULTS

OLP patients showed detected levels of anxiety, depression, and poor quality of life at baseline. No improvement in anxiety and depression was noticed after treatments. However, PBM and corticoid significantly improved the quality of life of OLP patients, considering the OHIP-14-T and the physical pain domain. The treatment with corticoid was more cost-effective than PBM.

CONCLUSIONS

Psychological distress was not improved after both treatments and PBM is as effective as corticoids in promoting a better quality of life in OLP patients, despite its higher cost.

CLINICAL RELEVANCE

This study highlights the need for additional therapeutic interventions in OLP patients, to early recognize and to manage the alterations in their psychological profile. Moreover, PBM is an effective therapy in OLP patient's quality of live and although it was a more expensive, the advantage of being a minimally invasive therapy associated with no side effects must be considered in clinical practice, especially in those patients with refractory disease.

TRIAL REGISTRATION

This study is registered at ClinicalTrials.gov; the registration number is NCT03320460, registered in 17/10/2017.

The Characteristics of Patients with Oral Lichen Planus and Malignant Transformation-A Retrospective Study of 271 Patients

Introduction: Oral lichen planus (OLP) is a chronic inflammatory disease with an unknown etiology rating among oral potentially malignant disorder. The aim of the study was to determine the epidemiological and clinical characteristics of the patients with OLP and rate of malignant transformation. Patients and methods: Data were obtained from the medical records of 271 patients referred to the Oral Medicine Unit at the University Hospital in Hradec Králové diagnosed with oral lichen planus in the period of 2003–2020. The records were retrospectively analyzed. The following clinical data were retrieved from the medical charts: gender, age, systemic diseases, alcohol and tobacco consumption, localization/clinical appearance of lesions, distribution of the lesions, presence of the symptoms, treatment provided and malignant transformation. Results: A total of 271 charts of patients with confirmed diagnosis of OLP were retrospectively analyzed, of whom, 66.4% (180/271) were women and 33.6% (91/271) were men. The mean age of the patients was 56.0 (18.2–85.0) years. The median follow-up of all patients was 15.2 months. Overall, 2 patients (2/271, 0.74%) meeting the above-mentioned criteria for malignant transformation were identified during the follow-up period. Both patients suffered from erosive type OLP and developed squamous cell carcinoma of the tongue. Conclusions: This retrospective study is in concordance with other studies showing the similar profile and clinical features of the patients with OLP. Malignant transformation rate was 0.74%.

Mussel Inspired Chemistry and Bacteria Derived Polymers for Oral Mucosal Adhesion and Drug Delivery

Ulceration of the oral mucosa is common, can arise at any age and as a consequence of the pain lessens enjoyment and quality of life. Current treatment options often involve the use of topical corticosteroids with poor drug delivery systems and inadequate contact time. In order to achieve local controlled delivery to the lesion with optimal adhesion, we utilized a simple polydopamine chemistry technique inspired by mussels to replicate their adhesive functionality. This was coupled with production of a group of naturally produced polymers, known as polyhydroxyalkanoates (PHA) as the delivery system. Initial work focused on the synthesis of PHA using Pseudomonas mendocina CH50; once synthesized and extracted from the bacteria, the PHAs were solvent processed into films. Polydopamine coating was subsequently achieved by immersing the solvent cast film in a polymerized dopamine solution. Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy confirmed functionalization of the PHA films via the presence of amine groups. Further characterization of the samples was carried out via surface energy measurements and Scanning Electron Microscopy (SEM) micrographs for surface topography. An adhesion test via reverse compression testing directly assessed adhesive properties and revealed an increase in polydopamine coated samples. To further identify the effect of surface coating, LIVE/DEAD imaging and Alamar Blue metabolic activity evaluated attachment and proliferation of fibroblasts on the biofilm surfaces, with higher cell growth in favor of the coated samples. Finally, in vivo biocompatibility was investigated in a rat model where the polydopamine coated PHA showed less inflammatory response over time compared to uncoated samples with sign of neovascularization. In conclusion, this simple mussel inspired polydopamine chemistry introduces a step change in bio-surface functionalization and holds great promise for the treatment of oral conditions.

Erosive oral lichen planus inflicts higher cellular stress than reticular type

BACKGROUND

Lichen planus is a chronic inflammatory mucocutaneous disease which frequently involves the oral mucosa. The most common types of oral lichen planus (OLP) are reticular (asymptomatic) and erosive (ulcerative) with malignant potentiality. The aims of the present study are to assess the cellular stress level in both types of OLP lesions with respect to oxidative stress, DNA damage and inflammation.

MATERIALS AND METHODS

Freshly diagnosed untreated 25 OLP reticular type and 25 OLP erosive (OLP-E) type patients aged 35-55 years were enrolled in the study along with age and sex-matched 25 healthy subjects as control. Tissue antioxidant enzymes were measured biochemically, single-cell DNA damage was measured by comet assay and the molecular markers for inflammation were assessed by using semi-quantitative reverse transcriptase-polymerase chain reaction. Statistical analyses were performed using one-way ANOVA and Tukey's post hoc test.

RESULTS

Oxidative stress was significantly greater in OLP-E type compared to the reticular. mRNA expression of cyclooxygenase-2 was significantly elevated (P < 0.0001) in erosive form, but such expression of nuclear factor kappa beta, tumor necrosis factor-alpha, Interleukin-6 and inducible nitric oxide synthase did not significantly differ between the two disease groups. Comet assay revealed a higher degree of DNA strand breakage in erosive lesions.

CONCLUSIONS

The unhandled free radicals may imbalance the homeostatic network toward pro-inflammatory, DNA damaging responses, creating a vicious cell-damaging spree resulting in stress. Molecular analyses showed that erosive lichen planus is more under stress than the reticular form.

Treatment of plaque-like oral lichen planus with CO2 laser

Background:

Oral lichen planus (OLP) is a chronic autoimmune disease, which annoys the patients for several years. It presents with various clinical forms. Although plaque-like form of OLP is usually asymptomatic, it could transform to a malignant lesion. Therefore, treatment considerations are essential to reduce the development of oral cancer. Laser therapy is a newer modality for treatment of plaque-like lesions.

Aims:

This study aimed to perform laser therapy for plaque-like lesions of OLP.

Methods:

We described some plaque-like OLP lesions evaporated with CO2 laser. The power of 4–7 watt as continuous wave (CW) and defocused mode was employed for evaporation. The complications and recurrence were evaluated in the follow-up sessions.

Results:

In some patients, mild keratotic lesions were observed in the follow-up sessions. Most patients were satisfied with treatment process and reported mild burning after treatment. No complication was observed in the patients.

Conclusion:

CO2 laser could be employed for OLP lesions; however, some degrees of recurrence may occur.

Analysis of the Efficacy of Two Treatment Protocols for Patients with Symptomatic Oral Lichen Planus: A Randomized Clinical Trial

Oral lichen planus (OLP) is a chronic, inflammatory, immune-mediated disease, which can alter the quality of life of patients. The aim of this randomized clinical trial was to compare the therapeutic efficacy of clobetasol oral gel 0.05% versus an anti-inflammatory in oral solution (mouthwash) in the management of patients suffering from symptomatic OLP. The secondary objective was to analyze which one of the two treatments induced a greater risk of developing side effects. Forty patients were assigned (20 patients for group), through a randomized design, to receive clobetasol gel 0.05% or an anti-inflammatory mouthwash, which contains calcium hydroxide, hyaluronic acid, umbelliferone and oligomeric pro-anthocyanidins) for three months. At baseline (T0) and after 3 months (T1), patients underwent dental and dermatological examinations to assess their symptoms (Numerical Pain Scale (NRS) score) and signs (Thongprasom score). Data were calculated using T-test for the dependent variable, Wilcoxon test and Mann-Whitney u test. Both clobetasol and anti-inflammatory resulted in a statistically significant reduction of signs, (p < 0.001 and p = 0.02, respectively) and symptoms (p < 0.001 for clobetasol and p = 0.02 for anti-inflammatory). In conclusion, the results evidenced that, compared to clobetasol, the anti-inflammatory was less effective in determining the reduction of signs and symptom in OLP patients.

Immunohistochemical evaluation of Langerhans cells in oral lichen planus and oral lichenoid lesions

OBJECTIVE

the aim of this study was to evaluate the density of Langerhans cells in oral lichen planus (OLP) and oral lichenoid lesions (OLL).

DESIGN

14 cases of OLP, 15 cases of OLL and 14 cases of oral inflammatory fibrous hyperplasia (OIFH), were selected for immunohistochemical analysis of CD1a, CD207 and S100 expression. The OIFH group was subdivided according to the presence (OIFHL n = 14) or absence (OIFHNL n = 14) of lichenoid inflammatory infiltrate. Positive cells were counted in intraepithelial and subepithelial areas. Results were analyzed by multivariate comparative analysis, correlation analysis, linear regression models and Student's T-test.

RESULTS

A significantly higher amount of CD207+ cells in OLL vs OLP was observed (p = 0.015). The prevailing reticular pattern observed was CD207^high for OLP (p = 0.0329). A statistically significant difference in the expression of CD1a and CD207 was observed for intraepithelial vs subepithelial areas (p = 0.024 and p=0.015, for CD1a and CD207, respectively). Significant correlations were also observed between the expression of CD1a + and CD207+ cells in the pathogenesis of OLP and OLL.

CONCLUSION

High levels of CD207+cells in OLP compared with OLL may help explain the differences in the immunopathogenesis of both diseases. Additionally, CD1a + and CD207+ cells appear to be more essential to immunopathogenesis of OLL than to the pathogenesis of OLP.

Global Prevalence and Incidence Estimates of Oral Lichen Planus: A Systematic Review and Meta-analysis

Importance

Integrated information on the global prevalence and incidence of oral lichen planus (OLP) is lacking.

Objective

To examine the global prevalence and incidence of OLP in a systematic review and meta-analysis.

Data Sources

A systematic review of population-based studies and clinic-based studies reporting the prevalence and incidence of OLP was performed using 3 electronic medical databases (Cochrane Database of Systematic Reviews, Embase, and MEDLINE) from their inception to March 2019. The search terms included "(lichen planus or LP) and (prevalence or incidence or epidemiology)." No language restriction was applied.

Study Selection

Observational descriptive studies investigating the prevalence and incidence of OLP were included.

Data Extraction and Synthesis

Data were extracted by continent, sex, and other characteristics. The risk of bias was assessed by the Joanna Briggs Institute Critical Appraisal Instrument for Studies Reporting Prevalence Data using random-effects models to synthesize available evidence.

Main Outcomes and Measures

The primary outcome was the prevalence (with 95% CIs) of OLP among the overall population and among subgroups. Between-study heterogeneity was assessed using the I2 statistic.

Results

Among 46 studies, the overall pooled estimated prevalence of OLP was 0.89% (95% CI, 0.38%-2.05%) among the general population (n = 462 993) and 0.98% (95% CI, 0.67%-1.43%) among clinical patients (n = 191 963). Among the 15 population-based studies, the prevalence of OLP was 0.57% (95% CI, 0.15%-2.18%) in Asia, 1.68% (95% CI, 1.09%-2.58%) in Europe, and 1.39% (95% CI, 0.58%-3.28%) in South America. Among the 31 clinic-based studies, the prevalence was 1.43% (95% CI, 1.12%-1.83%) in Africa, 0.87% (95% CI, 0.61%-1.25%) in Asia, 1.03% (95% CI, 0.51%-2.09%) in Europe, 0.11% (95% CI, 0.07%-0.16%) in North America, and 3.18% (95% CI, 0.97%-9.95%) in South America. The pooled prevalence of OLP by sex was 1.55% (95% CI, 0.83%-2.89%) for women and 1.11% (95% CI, 0.57%-2.14%) for men in the population-based studies and 1.69% (95% CI, 1.05%-2.70%) for women and 1.09% (95% CI, 0.67%-1.77%) for men in the clinic-based studies. In 5 clinic-based studies providing the age distribution of patients with OLP, the prevalence by age was 0.62% (95% CI, 0.33%-1.13%) among patients younger than 40 years and 1.90% (95% CI, 1.16%-3.10%) among patients 40 years and older.

Conclusions and Relevance

This study identified the global prevalence and incidence of OLP in terms of its spatial, temporal, and population distribution. The overall estimated pooled prevalence of OLP was 0.89% among the general population and 0.98% among clinical patients. A higher prevalence of OLP was found in non-Asian countries, among women, and among people 40 years and older. The findings should be considered with caution because of the high heterogeneity of the included studies.