As the field of oral pathology has evolved, the nomenclature and classification of oral mucosal diseases with a remarkable risk of malignant transformation have undergone several modifications. In 2005, the World Health Organization (WHO) introduced the concept of oral potentially malignant disorders (OPMDs) as an alternative to the terms for oral precancerous lesions and precancerous conditions. In the consensus report by the WHO Collaborating Center for Oral Cancer of 2021, OPMD is defined as "any oral mucosal abnormality that is associated with a statistically increased risk of developing oral cancer."This definition encompasses a range of conditions, in-cluding oral leukoplakia, oral submucous fibrosis, proliferative verrucous leukoplakia, oral lichen planus, and other lesions. In light of the complex etiology, unclear pathogenesis, and carcinogenesis of OPMDs, early and precise diagnosis and treatment can contribute to the secondary prevention of oral cancer. For this reason, this review, which aims to provide a basis for the precise clinical diagnosis of OPMDs, was performed. Its aim was achieved by reviewing the historical evolution and research progress of the nomenclature, classification, and histopathological diagnostic criteria of OPMDs.
Humans ; Mouth Neoplasms/diagnosis* ; Precancerous Conditions/diagnosis* ; Leukoplakia, Oral/diagnosis* ; Lichen Planus, Oral/pathology* ; Oral Submucous Fibrosis/pathology* ; Mouth Mucosa/pathology* ; World Health Organization

Lichen planus (LP) is a chronic, immune-mediated dermatosis, clinically characterized by the classic “5 P’s”: pruritic, purplish, polygonal, planar papules, and plaques. While typically LP is idiopathic, the Koebner phenomenon may trigger LP by trauma, infections, medications, or foreign substances such as, in this case, tattoo pigments. A 27-year-old Filipino male presented with a 10-month history of intensely pruritic papules and plaques involving both tattooed and adjacent nontattooed regions of the forearms. Lesions initially appeared as papules along the tattoo margins approximately 1 year after tattoo placement and subsequently, spreading to form confluent plaques. Despite multiple courses of high-potency topical corticosteroids, symptoms persisted with progressive lesion thickening. Dermoscopy was performed, but the findings did not conclusively indicate LP; therefore, a biopsy was done to confirm LP. Owing to the extent of involvement and lack of steroid response, the therapy was transitioned to tacrolimus 0.1% ointment applied twice daily. The patient experienced a marked reduction in pruritus, flattening of papules, residual postinflammatory erythema, and no reported adverse effects within 2 weeks. This case highlights the therapeutic potential of topical calcineurin inhibitors in managing LP, particularly in cases where there is resistance to corticosteroids. Tacrolimus 0.1% ointment may present a safe and effective alternative for disseminated or steroid-refractory LP, warranting consideration in clinical practice.

Lichen planus (LP) is a chronic inflammatory dermatosis with a prevalence of 0.1%-4%, typically affecting individuals aged 30-60 years. Isolated lip involvement is uncommon, seen in 0.51%-8.9% of cases, predominantly in middle-aged men. We report a 58-year-old male with well-controlled diabetes who developed isolated lower lip LP, initially misdiagnosed as herpes simplex virus infection and unresponsive to oral acyclovir. Dermoscopy and histopathology confirmed the diagnosis. The patient was managed with a novel regimen: Tacrolimus 0.1% ointment (morning) and tretinoin 0.025% cream (night), alongside sunscreen and petroleum jelly. After 4 weeks, marked improvement was observed with flattened lesions and reduced pruritus. This case underscores the potential efficacy of combining a calcineurin inhibitor and a retinoid as a corticosteroid-sparing alternative for localized LP. Clinically, this approach offers a valuable treatment option for patients with lip LP showing suboptimal response to initial corticosteroid therapy, minimizing steroid-related adverse effects and improving therapeutic outcomes.

Oral lichen planus (OLP) is a chronic and inflammatory oral mucosal disease that commonly affects middle-aged females. Most OLP cases might exhibit such symptom as pain, roughness and other discomfort, and more severe forms may show a high risk of developing oral cancer. Active preventive measure, precise diagnosis and standard therapeutic approach play a vital role in the management and prevention of OLP. This guideline is a revision on the base of trial in 2012, which mainly covers the following 8 aspects: etiology and medical records, clinical manifestations, pathological manifestations, diagnosis, differential diagnosis, laboratory examination, disease treatment and prevention, aiming at providing scientific evidence and guidance for the dental clinicians in diagnose and treatment of OLP.
Diagnosis, Differential ; Female ; Humans ; Lichen Planus, Oral/therapy* ; Middle Aged ; Mouth Neoplasms

Objective: To explore the expression of autophagy related factors microtubule associated protein 1 light chain 3B (LC3B), p62, autophagy key factor Beclin1 in oral lichen planus (OLP) tissues and their relationships with the clinicopathological characteristics of OLP, investigating the function and significance of autophagy in pathogenesis of OLP. Methods: Forty-one lesion tissues (OLP group, twenty-one cases of erosive OLP and twenty cases of non-erosive OLP) were selected from OLP patients visiting the Department of Periodontal and Oral Medicine, School and Hospital of Stomatology, Guizhou Medical University from October 2017 to December 2019. Fifteen cases of normal oral mucosal tissues (control group) were collected from oral and maxillofacial surgery at The Affiliated Stomatology Hospital of Guizhou Medical University during the same period. Protein and mRNA expression levels of LC3B, p62 and Beclin1 were detected by immunohistochemistry (IHC) and real-time quantitative PCR (RT-qPCR) in OLP lesions respectively. The protein expression levels of LC3B, p62, Beclin1 and ratio of LC3B-Ⅱ/LC3B-Ⅰ in sixteen cases (eight cases of erosive OLP and eight cases of non-erosive OLP) from the OLP group were detected by Western blotting (WB). The potential relationship between LC3B, p62, Beclin1, LC3B-Ⅱ/LC3B-Ⅰ ratio and clinical features of OLP were analyzed. Results: IHC results showed that the positive expression rates of LC3B and p62 proteins in OLP lesion tissues [LC3B: 68% (28/41); p62: 59% (24/41)] were higher than those in the control group [LC3B: 5/15; p62: 3/15] (LC3B: χ²=5.55, P=0.019; p62: χ²=5.55, P=0.015). The positive expression rates of LC3B and p62 proteins in the erosive OLP group [LC3B: 86% (18/21); p62: 76% (16/21)] were higher than those in the non-erosive OLP group [LC3B: 50% (10/20); p62: 40% (8/20)] (LC3B: χ²=4.50, P=0.034; p62:χ²=5.53, P=0.019). The positive expression rate of Beclin1 protein in the OLP lesions[20% (8/41)] was lower than that in the control group (7/15) (χ²=4.13, P=0.042), but was not statistically different between the two types of OLP (P>0.05). The RT-qPCR results showed that the mRNA expression levels of LC3B and p62 in OLP lesions [LC3B: 2.78 (1.59, 6.15); p62: 4.30 (2.34, 6.29)] were higher than those in the control group [LC3B: 1.05 (0.88, 1.21); p62: 1.12 (0.89, 1.36)] (LC3B: Z=-4.56, P<0.001; p62: Z=-4.78, P<0.001), and the mRNA expression levels of LC3B and p62 in the erosive OLP group were higher than those in the non-erosive OLP group (LC3B: Z=-2.87, P=0.004; p62: Z=-2.95, P=0.003). The mRNA expression level of Beclin1 in OLP tissues was lower than that in the control group (Z=-2.43, P=0.015), but the difference was not statistically significant between the two types of OLP (P>0.05). WB results showed that the LC3B-Ⅱ/LC3B-Ⅰ ratio was higher in the OLP lesions than that in the control group (t=-2.45, P=0.021), and the LC3B-Ⅱ/LC3B-Ⅰ ratio was higher in the non-erosive OLP group than in the erosive OLP group (t=-2.38, P=0.032). Spearman's correlation analysis showed that the ratio was negatively correlated with the clinical staging and the degree of basal cell liquefaction in OLP (clinical staging: r=-0.57, P=0.021; basal cell liquefaction: r=-0.54, P=0.032), but not with the disease duration and the degree of lymphocytic infiltration (P>0.05). Conclusions: Autophagy related factors LC3B, p62 and Beclin1 may play a role in the formation and progression of OLP lesions. The autophagy level was relatively lack in erosive OLP compared to non-erosive OLP, contributing to the increased local lesion destruction in erosive OLP. Abnormal cellular autophagy may play an important role in the formation of OLP lesions.
Humans ; Lichen Planus, Oral/metabolism* ; Beclin-1 ; Microtubule-Associated Proteins/metabolism* ; Autophagy ; RNA, Messenger/metabolism*

Oral lichen planus (OLP) is a chronic inflammatory oral mucosal disease with unclear etiology. Autoimmune thyroid diseases (AITD) is a type of autoimmune disease characterized by increased thyroid-specific antibodies. In recent years, more and more studies have found that the incidence of AITD is increased in OLP patients. The occurrence and development of OLP and AITD may be related to the expression of thyroid autoantigen in oral keratinocytes, the imbalance of thyroid hormone （Th）1/Th2 and Th17/Treg cell subsets, the abnormal quantity and function of follicular helper T cells and chemokines and the specific killing ability of CD8 T cells to target cells. In this article, the possible immune mechanisms involved in the coexistence of OLP and AITD are reviewed to provide insights for the diagnosis, treatment and prevention of these two diseases from the perspective of immunology.
Autoimmune Diseases/complications* ; Hashimoto Disease ; Humans ; Lichen Planus, Oral/complications* ; Mouth Mucosa ; Th17 Cells

OBJECTIVES: This study aimed to determine whether a correlation existed between CXC chemokine ligand 10 (CXCL10)-CXC chemokine receptor 3 (CXCR3) and CC chemokine ligand 17 (CCL17)-CC chemokine receptor 4 (CCR4) in the pathogenesis of oral lichen planus (OLP). METHODS: Peripheral blood of OLP patients (non-erosive and erosive groups) and healthy controls were collected, and T cells were isolated and purified. T cells were co-cultured with three groups: blank, anti-CXCR3, and anti-CCR4. CXCR3 and CCR4 expression were detected by flow cytometry, and CXCL10 and CCL17 were detected by enzyme-linked immunosorbent assay, respectively. RESULTS: The purities of T cells were all >95% in the three groups ( CONCLUSIONS Two axes interact with each other in the pathogenesis of OLP and may play different roles in its occurrence and development.
Chemokine CCL17 ; Chemokine CXCL10 ; Humans ; Lichen Planus, Oral ; Ligands ; Receptors, CCR4 ; Receptors, CXCR3

OBJECTIVE: To observe the efficacy and safety of Nocardia rubra cell wall skeleton (Nr-CWS) for the treatment of erosive oral lichen planus (EOLP). METHODS: Sixty patients with clinically and pathologically diagnosed EOLP were randomly divided into the experimental group and control group according to the random number. Patients in the experimental group were treated with lyophilized powder containing Nr-CWS combined with normal saline. Patients in the control group received topical placebo without Nr-CWS combined with normal saline. Changes in the EOLP lesion area and the patient's pain level were recorded at the timepoints of weeks 1, 2, and 4 after the two different treatments, respectively. The changes of the patient's REU scoring system (reticulation, erythema, ulceration), the visual analogue scale and the oral health impact score (OHIP-14) were compared between the experimental group and control group after treatment, and the safety indicators of the two groups at the initial diagnosis and after 4 weeks' treatment were also observed, respectively. RESULTS: Totally, 62 patients with clinically and pathologically diagnosed EOLP were enrolled, 2 of whom were lost to the follow-up, with 31 in the experimental group, and 29 in the control group. The mean age of the experimental group and control group were (52.9±12.4) years and (54.07±12.40) years, respectively. There was no significant difference in the oral periodontal index between the experimental group and control group. In the experimental group, the erosive area of oral lichen planus was significantly reduced 1, 2, and 4 weeks after the Nr-CWS's treatment (P < 0.05), the reduction rate was 81.75%, the patient's pain index was also decreased (P < 0.05), and in addition, the OHIP-14 was reduced (P < 0.05). The changes of the REU scoring system, the visual analogue scale and the OHIP-14 were significantly different between the experimental group and control group after treatment. There was no significant difference in the safety index between the two groups. CONCLUSION The priliminary data show that the Nr-CWS is effective and safe to treat EOLP.
Adult ; Aged ; Cell Wall Skeleton ; Humans ; Lichen Planus, Oral/drug therapy* ; Middle Aged ; Pain Measurement ; Rhodococcus

Background: Oral lichen planus is an idiopathic autoimmune inflammatory condition and oral lichenoid reactions are lesions that resemble oral lichen planus clinically and histopathologically, but develop secondary to various underlying causes. Oral lichenoid reactions have been reported to be caused by contact allergy to dental materials. This study aims to describe the characteristics of patients with a clinical and/or histopathological diagnosis of oral lichen planus who underwent patch testing in Hospital Kuala Lumpur, Malaysia. Methods: This is a 5-year retrospective study of patients who had oral lichen planus and had undergone patch testing at the Department of Dermatology, Hospital Kuala Lumpur, Malaysia between January 2015 and Cecember 2019. Patch tests were performed with European Baseline Series and relevant extended series, which include dental and metal series as well as patients’ own products. Patch test results were recorded according to the International Contact Dermatitis Research Group recommendation. Results: There were 41 patients with oral lichen planus who underwent patch test. The median age was 56 (range 21 to 73) with 70.7% of patients being female. There were 29 (70.7%) patients who developed at least one positive reaction. The most frequent sensitizing allergens were nickel sulfate (34.1%), gold(I)sodium thiosulphate dihydrate (22.0%), fragrance mix I (19.5%), cobalt chloride (14.6%), Peru balsam (12.2%) and sodium tetrachloropalladate (II) hydrate (12.2%). Current relevance was recorded in 16 patients (39.0%) and of these patients, 12 of them had positive patch test reactions to allergens found in dental materials such as dental fillings, dental implants, orthodontic braces, dentures and dental crowns. Conclusion Contact sensitization was detected in about 70% of our patients with oral lichen planus. The most common sensitizing allergen was nickel sulfate. Current relevance was found mainly towards dental materials.
Lichen Planus, Oral--diagnosis ; Dermatitis, Allergic Contact ; Department of Dermatology, Hospital Kuala Lumpur (Malaysia)

Oral lichen planus (OLP) is a common chronic inflammatory disease of the oral mucosa. The prevalence rate of OLP in adults is 0.5%-2%. The etiology and pathogenesis of OLP are still unclear. The pathogenesis of OLP may be related to the genetic polymorphism of some genes. Currently, the gene families, including tumor necrosis factor, interferon, interleukin, enzyme, and receptor, have been extensively studied. This work reviews related studies on gene polymorphism of OLP.
Adult ; Humans ; Lichen Planus, Oral/genetics* ; Mouth Mucosa ; Polymorphism, Genetic ; Tumor Necrosis Factor-alpha/genetics*