Oral mucous membrane pemphigoid in a group of Thai patients-A 15-year retrospective study.

Background/purpose: Mucous membrane pemphigoid (MMP) is a rare autoimmune disease affecting mucous membrane of the body. Oral involvement is common causing chronic and painful lesions. This study aimed to characterize oral MMP in a group of Thai patients and to analyze treatment regimens. Materials and methods: The files of patients attending Oral Medicine Clinic were retrospectively studied. Patients fulfilled diagnostic criteria of MMP were included. Chief complaints, medical and dental history, oral manifestations and investigations of individual patients were summarized. Treatment regimens and efficacy were also analyzed. Results: There were fourteen patients (age range 33-70 years) with a diagnosis of MMP. The prevalence of oral MMP was 0.51%. The lesions presented as vesicles, blood blisters, erosions, ulcers, erythema, either one type or in combination. Common complaints were chronic painful and bleeding gums. Gingival lesions were found in 13 of 14 patients (92.86%). The most common direct immunofluorescence findings were linear C3 at basement membrane zone (92.31%) followed by linear IgG deposition (84.62%). Most lesions were successfully managed with topical and/or systemic corticosteroids. The average time to control disease was 1.97 months (IQR, 0.69-12.73 months). Conclusion: Gingival lesions are very common in MMP. Mainstay of treatment is combination of systemic and topical corticosteroids. Multidisciplinary care including oral hygiene maintenance is necessary.

Detection of Human Papillomavirus and p16INK4a Expression in Thai Patients with Oral Squamous Cell Carcinoma.

This study investigated the prevalence of human papillomavirus (HPV) infection in oral squamous cell carcinoma (OSCC) cases, as well as the association between HPV presence and p16INK4a expression, in Thai patients with OSCC. Eighty-one formalin-fixed paraffin-embedded specimens of OSCC were obtained. DNA extraction was performed; this was followed by nested polymerase chain reaction analysis to determine HPV DNA status, using consensus primers for the L1 region of HPV. HPV subtypes were determined by DNA sequencing. HPV-positive specimens and HPV-negative specimens from age- and sex-matched patients were subjected to immunohistochemical analysis to determine p16INK4a expression status. Of the 81 OSCC specimens, eight (9.9%) exhibited HPV DNA; DNA sequencing confirmed that the viral subtype was HPV-18 in all eight specimens. These eight HPV-positive specimens, as well as eight HPV-negative specimens from age- and sex-matched patients, were subjected to immunohistochemical analysis to determine p16INK4a expression status. Three of eight (37.8%) HPV-positive specimens and three of eight (37.8%) HPV-negative specimens showed positive p16INK4a expression findings. However, we did not find a significant association between HPV status and p16INK4a expression status in our OSCC samples. In conclusion, the prevalence of high-risk HPV was low in this group of OSCC patients; no association between HPV status and p16INK4a expression status was identified.

An Unusual Presentation of Multiple Superficial Mucoceles Occurring with Oral Lichen Planus.

Superficial mucoceles, a rare variant of the mucocele occurring simultaneously with oral lichen planus, are uncommon. This report introduces a case of multiple superficial mucoceles developing with oral lichen planus in a 76-year-old Thai female and provides information to avoid misdiagnosis and over-management of this lesion. Pathogenesis and clinicopathological characteristics of this phenomenon are also discussed.

Effect of Nicotine and Porphyromonas gingivalis on the Differentiation Properties of Periodontal Ligament Fibroblasts.

OBJECTIVES: This study aimed to evaluate the effect of Porphyromonas gingivalis and nicotine on the in vitro osteogenic differentiation of periodontal ligament (PDL) fibroblasts. MATERIALS AND METHODS: PDLs were cultured in Dulbecco's modified Eagle's medium containing 10% fetal bovine serum at 37°C under 5% CO2 and 100% humidified atmosphere. Cells were incubated with various concentrations of nicotine and P. gingivalis extracts, and cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. To study cell differentiation, PDLs (5 × 104cells) were treated with the osteogenic differentiation medium containing 10 mM ß-glycerophosphate, 10 nM dexamethasone, 50 mg/mL ascorbic acid, 1 µM nicotine, and 50 µg/mL P. gingivalis lysate. mRNA samples were collected at 0, 7, and 14 days. Odontogenic-related gene expression, namely, Runt-related transcription factor 2 (Runx2), collagen type I (COL1A1), and alkaline phosphatase (ALP) was determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Calcified nodule formation was determined on day 28 using Alizarin Red S. Analysis of variance and Tukey's test were used to compare the difference among groups at significant level of p < 0.05. RESULTS: It showed that 50 µg/mL of P. gingivalis lysate and 1 µM of nicotine showed no toxicity to PDLs. Runx2, COL1A1, and ALP expression were found to decrease significantly after 7 days of treatment, while osteocalcin expression was found to decrease after 14 days. The nodule formation in the control group was much greater in both number and size of nodules than in experimental groups, which implied a positive sign of calcium deposition in controls. CONCLUSION: The results indicated that nicotine and P. gingivalis showed adverse effect on osteogenic differentiation properties of PDLs.

Genotyping of Candida albicans and Candida dubliniensis by 25S rDNA analysis shows association with virulence attributes in oral candidiasis.

OBJECTIVES: This study genotyped oral isolates of Candida albicans and C. dubliniensis by analyzing 25S rDNA transposable intron and evaluated their virulence attributes in oral candidiasis. DESIGN: C. albicans and C. dubliniensis were isolated from oral cavity of normal carriers (n = 100) and oral candidiasis patients (n = 100), genotyped by PCR, and virulence properties, namely, secreted phospholipase and proteinase activities (using an agar plate method) and binding to buccal epithelial cells, were determined. In addition, antifungal sensitivity was assayed for all Candida isolates. RESULTS: C. albicans genotypes A, B, C and D (C. dubliniensis) were identified. Genotype B was the most prevalent in both healthy and candidiasis groups and had highest buccal epithelial cell binding ability but lowest secreted phospholipase activity. Genotype C was the third most prevalent, with higher frequency in patients than normal carriers. Genotype A, the second most prevalent, was equally found in both groups. There were no significant differences in secreted proteinase activity among the three C. albicans genotypes. C. dubliniensis, the least prevalent, was more frequent in healthy carriers and demonstrated minimal levels of the virulence properties. When all Candida isolates were compared based on groups of subjects, only secreted phospholipase activity was significantly higher in isolates from candidiasis patients. All Candida isolates were susceptible to clotrimazole, fluconazole, miconazole and nystatin. CONCLUSIONS: Genotyping based on the 25S rDNA transposable intron region provided a simple method allowing studies of the pathogenicity of each genotype.