Oral epithelial dysplasia with lymphocytic immune response: clinicopathological characterisation of 44 cases.

AIMS: Oral epithelial dysplasia (OED) often exhibits a lymphocytic/lichenoid immune response (LIR), imparting histological resemblance to lichenoid mucositis and rendering diagnosis challenging. The clinical appearances of OED and lichenoid inflammatory processes are generally divergent, presenting as well-demarcated hyperkeratotic plaques and diffuse white and/or red mucosal change with variably prominent Wickham striae, respectively. To date, clinicopathological characterisation of OED with LIR, including clinical/gross appearance, has not been depicted. METHODS AND RESULTS: Cases of solitary OED with LIR for which a clinical photograph was available were identified in the authors' institutional files. Clinical and histological features were documented. In 44 identified cases, dysplasia was mild (19 of 44, 43.2%), moderate (19 of 44, 43.2%) and severe (six of 44, 13.6%). Clinically/grossly, all 44 cases (100.0%), presented as well-demarcated hyperkeratotic plaques lacking diffuse white-and-red mucosal change or Wickham striae. Histologically, OED with LIR exhibited numerous 'lichenoid' features beyond the lymphocytic band in the superficial lamina propria, including: leucocyte transmigration (38 of 44, 86.4%), spongiosis (37 of 44, 84.1%), Civatte/colloid bodies (36 of 44, 81.8%), basal cell degeneration (29 of 45, 65.9%), sawtooth rete ridges (11 of 44, 25.0%) and subepithelial clefting (7 of 44, 15.9%). CONCLUSIONS: Virtually any lichenoid histological feature may be seen in OED with LIR, representing a significant diagnostic pitfall. The typical clinical appearance of OED with LIR is of a well-demarcated hyperkeratotic plaque, characteristic of keratinising dysplasia and devoid of lichenoid features. This suggests that pathologist access to clinical photographs during diagnostic interpretation of biopsied white lesions, which represents opportunity to perform gross examination of the disease process, may reduce interobserver variability and improve diagnostic accuracy in this challenging differential diagnosis.

Childhood lichenoid granulomatous stomatitis: a case report and literature review / 口腔疾病防治

Objective@#To investigate the classification, clinical manifestations, diagnosis, differential diagnosis and treatment of oral lichenoid lesions and provide a reference for clinical practice.@*Methods@#Hospital ethical approval and patient informed consent were obtained. We report a case of oral lichenoid lesion in children and review the diagnosis and treatment of oral lichenoid damage in the literature.@*Results@#The patient experienced repeated rupture of the dorsal surface of the tongue with pain for more than 3 years. There was a large area of tongue back surface erosion with an irregular shape, surrounded by pearly-white lines. The left erosive area was accompanied by tissue hyperplasia, which was approximately 1.5 cm × 2.0 cm, with tough texture and broad masses. The pathological diagnosis of the patient was oral lichenoid lesion. After biopsy of the dorsal surface of the tongue, the pathological diagnosis of the patient was granulomatous inflammation. The final diagnosis of lichenoid granulomatous stomatitis was made on the basis of the patient's intraoral damage features, systemic history, medication history and histopathological findings. A review of the literature suggests that oral lichenoid lesions have an unknown etiology and need to be clinically differentiated from oral lichen planus, oral lichenoid drug reactions, oral lichenoid contact damage and chronic ulcerative stomatitis. The clinical treatment of oral lichen planus is based on the topical and/or systemic use of glucocorticoids.@*Conclusion@#There are still no uniform criteria for the classification and diagnosis of oral lichenoid lesions. They rely mainly on history taking, clinical manifestations and histopathological findings, and the treatment is mainly based on the topical and/or systemic use of glucocorticoids.

Oral Lichenoid Lesion following Dental Implant Placement and Successful Management with Free Gingival Graft: A Case Report with 10-Year Follow-Up.

Titanium and metal alloys are widely used in implants, crowns, and bridges in implant dentistry owing to their biocompatibility. In this case report of a 45-year-old female patient, multiple implants were placed in five different sextants at different time points. Notably, oral lichenoid lesions (OLL) occurred in three sextants following implant placement, strongly suggesting that the dental implants or prostheses were the causative factors for OLL. The lesion was of the reticular type with erythematous surroundings and was symptomatic. Although several conservative treatments, including repeated topical application of corticosteroids, were repeatedly continued, no discernible improvement or alleviation of symptoms was observed. Consequently, surgical excision and replacement of the lesion with a free gingival graft (FGG) harvested from the palatal soft tissue were performed. No clinical symptoms or recurrence of lesions were observed during 10 years of follow-up post-FGG.

A Novel Approach to Differentiating Erosive and Reticular Lichen Planus Based on the Percentage of Dental Surfaces With Metal Restorations.

Introduction Oral lichen planus (OLP) and oral lichenoid reaction (OLR) constitute clinical entities with strong but unclear etiologic relation to dental materials. The aim of this study was to evaluate a correlation between the clinical form of OLP/OLR and the number of dental metal restorations in the oral cavity thus utilizing an exposure to metal (EM) index.  Material and methods The study type is experimental, and the study design is characterized as semiquantitative research that belongs to the branch of experimental research. Twenty-nine patients were chosen based on clinical (either reticular or erosive clinical forms) and histologic findings suggestive of OLP/OLR. The files of patients were retrieved from the archives of the Department of Oral Medicine/Pathology, School of Dentistry, Aristotle University of Thessaloniki, Greece, during the period 2009-2019. The medical history of the patients did not include any disorder or medication associated with lichenoid lesions and the measurements took place concurrently with the establishment of the diagnosis, thus no treatment for the lichen planus had been administered prior to the measurements. Quantitative measurement of the percentage of dental surfaces restored through metal restorations and correlation with the clinical and histologic findings of OLP/OLR was evaluated. The EM index was evaluated on a scale of 1-3, which corresponds to the percentage of dental surfaces restored through metal restorations. The statistical analysis was performed with the Pearson chi-square test and the significance level was set at p≤0.05. Results The EM index was measured by dividing each tooth into five surfaces (occlusal, mesial, distal, buccal, lingual), subsequently multiplying the number of available teeth with the number 5 to calculate the total number of surfaces, and then counting the number of surfaces with metal restorations - both fillings and crowns (in case of metal-ceramic crowns, the respective dental surface is taken into account only in case of macroscopically exposed metal), dividing the number of surfaces with metal restorations with the total number of surfaces and multiply by 100 so that the results take the form of percentages (%) and finally classifying the percentages into three groups: 1: 0% metal restorations, 2: 1-25% metal restorations, 3: >26% metal restorations). The percentage in female patients ranged from 0% to 100%, whereas it ranged from 0% to 60% in male patients. According to the clinical form of the lichenoid lesion, the percentage ranged from 0% to 60% in reticular lichen planus cases and from 0% to 100% in erosive lichen planus cases. There was no statistical difference between lichen planus cases, in total, and in normal oral epithelium. However, the levels of EM were marginally similar between the reticular lichen planus and the erosive lichen planus (Fisher's exact test, p = 0.056). Therefore, it may be the case that the EM index is higher in erosive lichenoid lesions. Conclusion In our study, the EM index was higher in female patients and in erosive lichenoid lesions. These findings should be tested and supported by larger samples of patients since the aforementioned Fisher's Exact Test, p = 0.056 could fall below the threshold of 0.05 if more patients were included. This is the first attempt to establish a novel approach to differentiating erosive and reticular lichen planus based on the percentage of dental surfaces with metal restorations.

Use test with l-carvone in toothpaste on sensitized individuals.

BACKGROUND: The mint flavour carvone (l-carvone) is considered a weak contact allergen. However, contact allergy to carvone is more prevalent in patients with oral lichen planus or oral lichenoid lesions (OLP/OLL). OBJECTIVE: Our aim was to investigate how carvone affects sensitized individuals through a use test with toothpaste containing carvone. Non-flavoured toothpaste served as control. METHODS: Subjects were patch tested prior to the use test-14 subjects allergic to carvone (11 with OLP/OLL), 20 subjects with OLP/OLL and 3 healthy controls. The month-long use test comprised of using toothpaste twice daily. Subjects were examined fortnightly. Clinical signs were assessed with a mucosal scoring system. The subjects' oral health-related quality of life was measured with the oral health impact profile (OHIP-49). RESULTS: Local reactions to the carvone toothpaste presented as aggravated OLL (7/10) and peri-oral eczema (2/10) in allergic subjects. They also had significantly higher mucosal and OHIP scores compared with those receiving non-flavoured toothpaste. CONCLUSION: In sensitized individuals, oral exposure to carvone gives aggravated oral lesions and/or peri-oral eczema. The lesions mimic OLP and allergic individuals are therefore at risk of not being assessed with regard to flavour contact allergy.

Histopathology of oral lichen planus and oral lichenoid lesions: An exploratory cross-sectional study.

OBJECTIVE: To better characterize the histopathology of oral lichen planus and oral lichenoid lesions and to highlight the differences between them in order to support the clinician in the diagnostic and therapeutic management of such conditions. SUBJECTS AND METHODS: Fifty-five patients, clinically diagnosed with oral lichen planus (n = 25) or oral lichenoid lesions (n = 30), were consecutively enrolled in the present study. Subsequently, one blind pathologist reviewed all the biopsy specimens of enrolled subjects following a specific protocol to provide a detailed histopathological description. Demographic, anamnestic, and clinical data were also recorded from all the participants. Patients' data were analysed and compared using the chi-squared test, to provide distinguishing features between the studied conditions. RESULTS: We found a higher and statistically significant number of eosinophils in the oral lichenoid lesions compared with the oral lichen planus group (p < 0.01), an equally promising result was seen regarding plasma cells, which were more represented (p = 0.05) in the oral lichenoid lesions than in the oral lichen planus cases. No statistically significant differences were detected in demographic, anamnestic and clinical data. CONCLUSION: A mixed lichenoid inflammatory infiltrate, consisting of eosinophils and plasma cells, could be used as reliable histological features for the diagnosis of oral lichenoid lesions, as long as compared with findings obtained from the patients' history and clinical examination.

Narrow-band imaging features of oral lichenoid conditions: A multicentre retrospective study.

OBJECTIVE: Narrow-band imaging (NBI), which highlights epithelial intrapapillary capillary loops (IPCLs) classified into five patterns (0 toIV) with increasing correlation to malignancy, has demonstrated effectiveness for detection of oral squamous cell carcinoma (OSCC). Lack of standardised procedures limits its use for routine inspection of oral lichenoid lesions including oral lichen planus (OLP), oral lichenoid lesion (OLL) and oral lichenoid reaction (OLR). The aim of this study was to analyse IPCL patterns of such lesions, assessing correlations with histopathological outcomes. MATERIALS AND METHODS: A multicentre, retrospective study was performed on 84 patients who underwent NBI and subsequent biopsy for suspected OLP/OLL/OLR. Patients were examined with Evis Exera III NBI system. Recorded NBI video endoscopies were evaluated to assess IPCL patterns and correlated with histopathological outcomes. RESULTS: No significant differences were detected among OLP/OLL/OLR on NBI inspection. All lichenoid lesions were significantly related to low-grade (0-II) IPCL patterns, clearly distinguishable from OSCC, showing pattern IV (p < 0.05). CONCLUSIONS: NBI cannot discern among OLP/OLL/OLR lesions. Interpretation should be modulated when assessing lichenoid lesions. NBI has potential to discern malignant transformation occurring in lichenoid lesions undergoing long-term follow-up, as IPCL pattern IV may be used as a clinical marker of malignancy arising in chronic inflammatory lesions.

Group 1 and 3 innate lymphoid cells are increased in oral lichen planus and oral lichenoid lesions.

OBJECTIVES: Innate lymphoid cells (ILCs) are vital innate immune cells cooperating with T cells. While their phenotypes and functions in oral mucosa kept unclear yet. In the present study, the relative proportions and distribution of different ILC subsets in oral mucosa of oral lichen planus (OLP), oral lichenoid lesions (OLL), and controls were compared. SUBJECTS AND METHODS: Oral mucosal samples were collected from control (n = 29), OLP (n = 20), and OLL (n = 22) donors. ILCs subsets were characterized in single-cell suspensions by flow cytometry. Immunohistochemistry was performed to locate the CD127+ cells in situ. RESULTS: ILCs were present in healthy and increased infiltration in OLP/OLL (p = 0.0092, p = 0.0216). Infiltration of ILC1 increased in OLP/OLL mucosa (p = 0.0225, p = 0.0399), as did the infiltration of ILC3 increase in OLL mucosa (p = 0.0128). The ILC2/ILCs ratio was significantly reduced in OLP and OLL (p = 0.0124, p = 0.0346). CD127+ cells were mainly located closely at the basement membrane. CONCLUSIONS: The results of increased ILC1, decreased ILC2, and increased ILC3 suggested that changes of ILC distributions in oral mucosa may be relevant to persistent inflammation in local tissues, by promoting immune factors and weakening repair capacity.

Oral lichenoid lesion simultaneously associated with Castleman's disease and papillary thyroid carcinoma: a rare case report.

BACKGROUND: Oral lichenoid lesion (OLL) is a term used to describe oral lesions that have clinical and/or histopathological features similar to oral lichen planus (OLP), but it is thought to be caused by specific triggers or systemic conditions and presents higher malignant transformation rate than OLP. To date, OLL simultaneously complicated with Castleman's disease (CD) and papillary thyroid carcinoma (PTC) has not been reported. Reporting from such disorders is crucial to avoid misdiagnosis and help in timely intervention. CASE PRESENTATION: We report a rare case of a 39-year-old female with extensive ulcerated lesions on the oral mucosa, diagnosed as OLL by histopathology. Routine oral treatment was scheduled to control the OLL, while the oral lesions remained unhealed. Computed tomography examination was performed after the oral treatment and revealed thyroid and mediastinal masses, which were then surgically removed and pathologically diagnosed as PTC and CD, respectively. Two months after complete excision of the neoplasms, the oral lesions showed obvious alleviation. With subsequent treatment for oral lesions, the patient's OLL healed. CONCLUSIONS: This is the first reported OLL case simultaneously associated with CD and PTC. This case reminds us to focus on the underlying etiologies of OLL and the multidisciplinary collaboration for oral lesions associated with systemic diseases.

Onset of Oral Lichenoid Lesions and Oral Lichen Planus Following COVID-19 Vaccination: A Retrospective Analysis of about 300,000 Vaccinated Patients.

Introduction: Onset of oral lichenoid lesions (OLL) or oral lichen planus (OLP) can be rare adverse reactions to vaccines. Recently, the first solitary cases were reported after COVID-19 vaccination. The aim of the present study was to assess if an increased frequency of OLL/OLP can be found after COVID-19 vaccination within a large real-world cohort. It was assumed that the incidence of OLL/OLP was significantly higher in subjects who received COVID-19 vaccine (cohort I) compared to individuals who were not vaccinated (cohort II). Patients and Methods: Initial cohorts of 274,481 vaccinated and 9,429,892 not vaccinated patients were retrieved from the TriNetX database (TriNetX, Cambridge, Massachusetts, USA), and matched for age, gender and the frequency of use of non-steroidal anti-inflammatory drugs, beta blockers, and angiotensin-converting enzyme inhibitors. Results: After matching each cohort, we accounted for 217,863 patients. Among cohort I, 146 individuals had developed OLL/OLP within 6 days after COVID-19 vaccination (88 and 58 subjects had received mRNA- and adenovirus vector-based vaccines), whereas in cohort II, 59 patients were newly diagnosed with OLL/OLP within 6 days after having visited the clinic for any other reason. The risk of developing OLL/OLP was calculated as 0.067% vs. 0.027%, for cohorts I and II, whereby the risk difference was highly significant (p < 0.001; log-rank test). RR and OR were 2.475 (95% CI = 1.829; 3.348) and 2.476 (95% CI = 1.830; 3.350), respectively. Discussion: The hypothesis was confirmed. Accordingly, the obtained results suggest that the onset of OLL/OLP is a rare adverse drug reaction to COVID-19 vaccines, especially to mRNA vaccines. Thus far, it remains unknown if specific components of the formulations cause a type IV hypersensitive reaction corresponding to OLL, or if the immune response post vaccination triggers a T cell-driven autoimmune reaction directed against the basal layer of keratinocytes of the oral mucosa in terms of OLP. Although OLL and OLP are both classified as premalignant lesions, spontaneous remission may be expected over time, at least in the case of OLL. Therefore, the presented findings should not place any limitation toward the use of COVID-19-vaccines in broad levels of the population.

Liquen plano oral: recomendaciones para su diagnóstico y tratamiento / Oral lichen planus: recommendations for diagnosis and treatment

El liquen plano corresponde a una enfermedad crónica de naturaleza inmuno-inflamatoria que puede presentarse en piel y mucosas, siendo la mucosa oral de las zonas más frecuentemente afectadas, incluso como primera única manifestación de la enfermedad. Su etiología no se encuentra totalmente dilucidada, sin embargo, se atribuyen mecanismos autoinmunes como principal causa de la enfermedad. El liquen plano oral (LPO) presenta un amplio espectro de manifestaciones clínicas, pudiendo presentarse como lesiones rojas, blancas o combinaciones de ambas. Sus diversas formas de presentación en la mucosa oral, en conjunto con una histopatología a veces poco específica, determinan que en varios casos su diagnóstico sea complejo para clínicos no familiarizados con la enfermedad. El tratamiento del LPO se enfoca en reducir los síntomas asociados a las lesiones, siendo los corticoides tópicos los fármacos de primera línea. En caso de que el tratamiento con corticoides tópicos no logre controlar la sintomatología, el tratamiento de segunda línea incluye inhibidores de calcineurina o corticoides sistémicos, los que deben ser utilizados con precaución debido a los efectos adversos asociados a estas drogas. La OMS clasifica al LPO como un desorden potencialmente maligno con una tasa de malignización anual estimada en 1.5%-5%, lo que realza la importancia de un correcto diagnóstico y control rutinario, aún en aquellas formas clínicas asintomáticas. Esto último con el fin de poder detectar de manera oportuna cambios clínicos que sugieran su progresión hacia un carcinoma oral de células escamosas.

Lichen planus is a chronic immunological disorder affecting skin and mucous membranes, being the oral cavity one of the more affected areas even as a first or only manifestation of the disease. Its etiology is unclear, but it has been associated with the activation of autoimmune mechanisms. Oral lichen planus (OLP) has a wide spectrum of clinical manifestations including a variety of white lesions, red lesions or a combination of both. In addition, its histopathological features are not always specific. Because of the above, the diagnosis of OLP can be challenging, especially for clinicians who are not entirely familiarized with the disease. OLP treatment is aimed in reducing pain and discomfort, usually with topical steroids. If treatment with topical steroids is unsuccessful, second line treatments include calcineurin inhibitors and systemic steroids. Care has to be taken when using these drugs as they can have considerable adverse side effects. OLP is classified by the WHO as a potentially malignant disorder with a malignant transformation rate estimated between 1.5% and 5%. Thus, its correct diagnosis and proper follow-up are essential even in asymptomatic forms of the disease. This to detect early clinical changes indicative of malignant transformation to an oral squamous cell carcinoma (OSCC).

Comparative evaluation of prevalence and phenotypic variations of Candida species in patients of oral lichen planus and oral lichenoid lesions with healthy individuals - A prospective microbiological study.

Context: Candida isolates might exaggerate the development and advancement of oral lichen planus (OLP) alone or together with other factors. There is a differing pathogenic potential of various Candida species. Since Candida species isolated from OLP and oral lichenoid lesions (OLL) have shown to be resistant to commonly used antifungal agents, identification of Candida species may play a pivotal role in its successful clinical management. Aim: The aim of the study was to evaluate and compare the prevalence and phenotypic variations of Candida species in patients of OLP and OLL with healthy controls. Subjects and Methods: This prospective microbiological study was conducted in the institution using indirect microscopic examination. The sample comprised of 40 clinicohistopathologically diagnosed cases of the study group (OLP and OLL) and 40 cases of control group (healthy individuals). Statistical Analysis Used: The data collected was statistically analyzed using the Chi-square test and Fisher's exact test with the SPSS 20.00 software. Results: The prevalence of Candida albicans was higher in the control group (28.10%) as compared to the study group (24.60%) and this difference was statistically significant. An increased frequency of non C. albicans species was seen in the study group, in decreasing order of Candida glabrata (40.70%), Candida tropicalis (22.20%), Candida krusei (22.20%) and Candida guilliermondii (3.70%), as compared to the control group. Conclusion: Non C. albicans species were the predominant pathogens associated with the study (OLP + OLL) group. It is important to identify the infecting strains of Candida because isolates of Candida species differ widely, both in their ability to cause infection and also in their susceptibility of resistance to antifungal agents. Thus, phenotypic speciation of Candida is emerging as a necessary trend to highlight the need of administering appropriate antifungal therapy.

Retrospective Study of Oral Lichen Planus and Oral Lichenoid Lesions: Clinical Profile and Malignant Transformation.

Statement of the Problem: Oral lichen planus (OLP) and other oral lichenoid lesions (OLL) are reported to have the potential of malignant transformation and dysplastic changes, turning into oral squamous cell carcinoma (SCC). While the world health organization (WHO) has classified OLP as a precancerous lesion of the oral cavity, there is still much debate among researchers about its risks and malignancy potential. Purpose: The present study aimed to determine malignant transformation in OLP and OLL and understand related risk factors. Materials and Method: This retrospective study was performed on 356 patients of the Oral Medicine Department of Dental School of Kerman Medical University from 1998 to 2020. All patients' records were gathered. In addition, patients were followed up routinely. Second biopsy was taken as needed. The samples, previously taken from the patients, were re-evaluated according to WHO histopathologic criteria for diagnosing OLP, OLL, dysplasia, and SCC by an experienced pathologist and compared with first reports. Results: Dysplastic changes were observed in 6.2% of the patients. In more than half of the patients, dysplastic changes were present right from the start and 2.20% of the patients had experienced dysplastic changes averagely within 2.05 years of the onset of lesions. Multiple logistic regression showed that the risk of dysplasia increases with aging (p= 0.013), smoking (p= 0.0001), and thyroid disorders (p= 0.008). Conclusion: Given the rather high prevalence of oral lichen planus and lichenoid lesions, further research appears to be needed to determine the etiology of these lesions, malignant transformations, and the factors affecting this probability. Considering the findings, it is imperative to meticulously record the information of all patients with oral lichen planus and lichenoid lesions in the initial examinations as well as close follow-ups and employ diagnostic tools such as toluidine blue staining or even repeat biopsy when necessary.

Correlation between Metal Ions and Cytokines in the Saliva of Patients with Oral Lichenoid Lesions.

PURPOSE: We aimed to investigate the effect of metal ions from oral prostheses (OPs) released into the saliva of patients with oral lichenoid lesions (OLLs). MATERIALS AND METHODS: Subjects (n=183) were divided into four groups according to the presence or absence of OLL and OP. Concentrations of the metal ions titanium, chromium (Cr), cobalt (Co), nickel (Ni), palladium (Pd), silver (Ag), platinum (Pt), gold (Au), and zirconium (Zr) were measured using a laser-ablation microprobe inductively coupled to a plasma mass spectrometer. Saliva levels of interleukin (IL)-6, IL-1ß, IL-8, and tumor necrosis factor-α were detected using an enzyme-linked immunosorbent assay. The reticulation/keratosis, erythema, and ulceration (REU) scoring system was used to assess the severity of OLL. RESULTS: Mean concentrations of IL-6 and IL-8 were statistically higher in OLL patients with OPs. The concentration of Ni was high in OLL groups. The concentrations of Cr, Ni, and Au ions in the saliva were positively correlated with IL-8. REU scores were positively correlated with salivary concentrations of IL-6 and IL-8, as well as with concentrations of Cr, Ni, and Au. CONCLUSION: Increased concentrations of metal ions, especially Ni, in saliva were positively correlated with IL-8 and showed positive correlations with the severity of OLL.

Inter-Observer and Intra-Observer Variations in the Assessment of Epithelial Dysplasia in Oral Lichenoid Diseases.

Oral lichen planus (OLP) and oral lichenoid lesions (OLL) can both present with histological dysplasia. Despite the presence of WHO-defined criteria for the evaluation of epithelial dysplasia, its assessment is frequently subjective (inter-observer variability). The lack of reproducibility in the evaluation of dysplasia is even more complex in the presence of a lichenoid inflammation. We evaluated dysplasia in 112 oral biopsies with lichenoid inflammation in order to study the inter-observer and the intra-observer variability.

Observer agreement in the diagnosis of oral lichen planus using the proposed criteria of the American Academy of Oral and Maxillofacial Pathology.

BACKGROUND: Oral lichen planus (OLP) is a common chronic inflammatory condition with an undefined malignant transformation potential. There have been many attempts at providing a specific definition of OLP without conclusive outcomes. A new set of diagnostic criteria was proposed in 2016 by the American Academy of Oral and Maxillofacial Pathology (AAOMP) in an endeavour to resolve this issue, and this has not yet been evaluated. This study aimed to assess the utility of AAOMP proposed criteria for the diagnosis of OLP. METHODS: Five pathologists blindly assessed a cohort of 215 digital whole slide images (WSI) obtained from haematoxylin and eosin-stained microscopic slides. Forty-six WSI were included twice to assess the intra-observer agreement. Included cases were diagnosed clinically as either OLP or oral lichenoid reaction. Each pathologist was asked to utilize the AAOMP histopathological criteria while assessing slides. The variations in diagnoses were assessed by unweighted kappa statistics. RESULTS: The level of intra-observer agreement was very good (0.801 to 0.899). The level of inter-observer agreement among the observers varied from good (0.658) to very good (0.842) when the responses were categorized as evident/compatible OLP versus no OLP and was good (0.62 to 0.725) when the responses were categorized as evident OLP, versus compatible OLP, versus no OLP. The clinico-pathological correlation was 87.6%. CONCLUSION: A reliable level of agreement can be achieved by pathologists for the diagnosis of OLP using the AAOMP criteria for differentiation between lichenoid and other conditions. There are still limitations in discriminating OLP from oral lichenoid lesions microscopically.

The role of CD68+ and CD163+ macrophages in immunopathogenesis of oral lichen planus and oral lichenoid lesions.

Macrophages are phagocytic cells with essential participation in immunological events of the oral cavity. However, the role of these cells in oral lichen planus (OLP) and oral lichenoid lesions (OLL) remains unclear. The present study aimed to evaluate the density of macrophages in OLP and OLL, and to compare it with that of oral inflammatory fibrous hyperplasia (OIFH) (control group). 14 cases of OLP, 14 cases of OLL and 14 cases of OIFH were selected for immunohistochemical analysis of CD68+ (M1) and CD163+ (M2) macrophage expression. CD68+ and CD163+ macrophages densities were measured in the intraepithelial and subepithelial areas. The statistical tests used were multivariate analysis of variance, as well as a correlation and linear regression. OLP has more CD68+ macrophages when comparing with OLL (p = 0.001) and OIFH (p = 0.045). There is a very strong relationship between the macrophages types (p < 0.0001) in OLP and OLL. The linear regression showed that to OLL development (p < 0.0001/R2' = 0.9584), the presence of different types of macrophages are more essential than to OLP (p < 0.0001/R2' = 0.8983). However, in the OLP these dependencies are also largely. CD68+ macrophages may be associated with immunopathogenesis of OLP, indicating a pro-inflammatory activity and regulatory role in the type of T-cell response. Besides, CD68+ macrophages can cooperate in the diagnosis of OLP. These results are essential to future studies that seek a therapeutic target for OLP and OLL.

Concurrent chronic hyperplastic candidosis and oral lichenoid lesion as adverse events of secukinumab therapy.

Secukinumab (Cosentyx®) is an IL-17A inhibitor which is used for the management of psoriasis, active psoriatic arthritis or ankylosing spondylitis. Oral adverse events of secukinumab therapy are not widely appreciated. This article highlights the presentation of two concurrent oral adverse events of secukinumab therapy; namely chronic hyperplastic candidosis (CHC) and oral lichenoid lesion (OLL). This is the first documented case report of CHC occurring as a consequence of secukinumab therapy, and represents a new adverse effect which general and specialist oral health practitioners should be aware of. This case highlights the importance of correlating the presence of oral lesions with the patient's medical history, keeping up to date with the development of new medications and pharmacotherapeutics, having a deep understanding of underlying biological processes related to various oral diseases, and appreciating the use of clinical adjunctive devices. Accurate diagnosis is key to formulating a correct management plan.

Malignant transformation of a clinically and histologically healed lichenoid lesion after amalgam removal: A case report and literature review.

Lichenoid contact lesions (LCLs) frequently develop in close contact with amalgam restorations and may regress after amalgam removal, especially when patch testing is positive to amalgam components. However, established criteria to define true LCLs healing are missing and clinical disappearance of the lesion may not always correspond to a complete regression of histological lichenoid tissue reaction. Similarly to other lichenoid lesions of the oral cavity, LCLs are included among potentially malignant disorders although its malignant transformation remains controversial. As a result, with no clear indications for neoplastic risk assessment, the management of patients with LCLs may be challenging. The present report describes the unusual case of an oral squamous cell carcinoma (OSCC) arising in the same site where 6 years before an amalgam-associated LCL had clinically and histologically healed after restoration replacement. A review of the few literature reports of amalgam-associated LCLs developing to OSCC is also provided.

Oral lichen planus and lichenoid lesions: what's new?

In recent years, a large number of studies have been published evaluating the therapy of oral lichen planus. In addition to standard medication such as topical glucocorticoid therapy, substances such as Aloe vera, hyaluronic acid, and treatments from traditional Chinese medicine have also been investigated. It is not always easy for dental practitioners to find an adequate therapy according to the clinical picture. This article presents therapies for dental practitioners who do not focus on treating patients with oral mucosa diseases. Oral lichenoid lesions, which are clinically and histologically similar, must be distinguished from oral lichen planus. Before starting therapy, it is necessary to differentiate between drug- and contact-related variants. Both clinical features have in common that according to the World Health Organization (2017) they belong to the class of potentially malignant disorders. Accordingly, these patients must be referred to a regular, and in oral lichen planus patients, lifelong, recall.