Porphyromonas gingivalis was shown to accelerate atheroma formation in murine models such as apolipoprotein E knockout (ApoE-KO) mice and BALB/c. apoE-deficient spontaneously hyperlipidemic (C. KOR-Apoe^shl) mice. The purpose of this study is to characterize mouse gender and strain differences in P. gingivalis-induced atherosclerosis. Male and female ApoE-KO mice (10 weeks old) and age- and sex-matched C. KOR-Apoe^shl mice were intravenously injected with P. gingivalis three times a week for 3 weeks. Mice were then killed at 14 weeks. Atherosclerotic plaques in the proximal aorta were determined by Oil Red O staining. Serum lipid parameters (total cholesterol, TC; high density lipoprotein, HDL; and low density lipoprotein, LDL) and body weights were evaluated. P. gingivalis injection significantly enhanced the formation of atherosclerotic plaque in both ApoE-KO and Apoe^shl mice. Moreover, atherosclerotic lesion area was slightly larger in ApoE-KO mice than in Apoe^shl mice, while both model mice displayed similar body weight gain regardless of bacterial infection. The weight gain of male was larger than that of female in the period, and the TC of Apoe^shl mice was higher than that of ApoE-KO mice. Furthermore, P. gingivalis injection had elevated serum TC and LDL levels compared to the non-injected Apoe^shl mice group. These results suggest that P. gingivalis induces atherosclerosis in both ApoE-KO and Apoe^shl mice subsequently increasingTC and LDL levels. Thus, the Apoe^shl mice may serve as a substitute for ApoEKO mice at the point of it being more natural and superior in examination of temporal change of morbidity, if we take account the import cost and the complication of maintenance of genetically modified mice.

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Oral fibrous hyperplasias (OFH) are thought to result from hyperplasia of collagen fibers. However, details regarding the presence of elastic fibers and reticular fibers other than collagen fibers in OFH are unclear. Therefore, this study focused on elastic fibers in the connective tissue with regard to OFH, and assessed the histopathological, histochemical, and immunohistochemical distribution of the elastic fibers.All cases of OFH (120 cases) were performed Elastica van Gieson (EvG) staining, and the distribution of elastic fibers was assessed using image analysis (binarization). Cases were classified into 2 groups; one group with elastic fibers (EF+ group) and one group without elastic fibers (EF−group).Elastic fibers were observed in 20 cases of fibroma of the buccal mucosa, 20 cases of fibroma of the labial mucosa, 19 cases of fibroma of the dorsal surface of tongue, 8 cases of fibroma of the gingiva, 1 case of fibrous epulis, and 1 case of fibromatous epulis. Histopathologically, elastic fibers were observed with mingled hyperplastic collagen fiber bundles and extended in the lesion. The distribution quantity of elastic fibers was fibroma of labial mucosa and buccal mucosa, and there were fewer elastic fibers in fibrous epulis and fibromatous epulis. Immunohistochemically, spindle cells in all cases of OFH were diffusely positive for Vimentin and negative for Actin, and CD34-positive spindle cells were interspersed into the connective tissue in EF+ group.In conclusion, elastic fibers were observed in 57.5% of OFH cases. The distribution of these fibers was site-specific, and differed from the collagen fibers that constituted OFH. CD34 positivity was observed in the spindle cells constituting OFH accompanied by elastic fibers, and undifferentiated mesenchymal cells around myogenic blood vessels near the lesion were related to the formation of a part of elastic fibers that constituted OFH.

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Antimicrobial peptides (AMPs), including defensins and cathelicidins, are widely distributedin cells and tissues as the host defense mechanism to prevent microbial invasion. Various barriers and secretory epithelial cells produce AMPs either constitutively or inducibly. It is widely accepted that defensins and cathelicidins are expressed in various mucosal tissues within highly regulated processes, which pathogenic and commensal agents might affect in a different way.
In this study, we examined the production of AMPs in both genetic and protein levels in mice, which were orally administered with suspended natto, a traditional Japanese fermented soybean product. A significant induction of the murine cathelicidin (cathelinrelated antimicrobial peptide; CRAMP)-specific mRNA was detected in not only the small intestine but also oral mucosa in mice fed a natto suspension. In addition, the expression of CRAMP in plasma was also confirmed by ELISA. Our result suggests that, when mice were administered natto, the fermentation product might have activated the oral immune system through the intestines, resulting in the production of AMPs in oral mucosa.

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Leukoplakia is the most common potentially malignant lesion of the oral mucosa. Studies on the risk factors of oral leukoplakia (OL) are relatively scarce. The present study was planned to assess the clinical risk factors of OL in our institution, which represents a sample of the Western UP population, based on the clinical status of OL patients spanning a period of eight years. The clinical and pathological data (age, sex, lesion location and presence/absence of dysplasia) were analyzed in these patients. Possible relationships between habitual tobacco use and lesion location were explored. The data obtained showed that habitual bidi smoking was prevalent among elderly males, while buccal mucosa was the most affected site by this lesion. Applying the Z-test for double sample proportions, a significant difference was observed for the buccal mucosa, labial mucosa, tongue and habitual smoking (1% level of significance, p<0.01) between the two age groups. A significant difference was observed between habitual tobacco use and various degrees of dysplasia (Fisherʼs exact test=0.00008, p<0.05). The present study underlines the role of habitual tobacco use in the etiology of OL in the Western UP population of India. Rigorous anti-smoking measures need to be taken in this region in order to prevent transformation into oral cancer.

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Multi-observer assessment involves the assessment of a personʼs work behavior by more than one colleague at the same time for the purpose of human resource development and capacity building. In the medical field, multi-observer assessment is employed to provide formative feedback during regular one-on-one meetings in order to increase the professional competence of medical residents, but it is rarely used in dental medicine. This report describes multi-observer assessment of the performance of trainee dentists at cooperative-type facilities. A total of 70 trainee dentists were assessed in the present study. For method of an investigation, a supervising dentist, a dental hygienist, and a receptionist assessed the professionalism and communication skills of the trainee dentists. There were significant differences of the average scores of assessment about the professionalism of the trainee dentist by all reviewers (p<0.01, p<0.05).There was a positive correlation between the average scores assigned by the supervising dentist and the dental hygienist (r=0.62, p<0.001,), as well as between the scores assigned by the dentist and receptionist (r=0.53, p<0.001,) or the dental hygienist and receptionist (r=0.78, p<0.001). These results suggest that there is a strong correlation between assessment by dentists, dental hygienists, and receptionists. The assessment that includes the perspective of the healthcare service recipients (patients) is needed in the future.

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Superselective arterial infusion therapy has recently played an important role in the treatment of head and neck tumors. We report, herein, an extremely rare case of tongue necrosis as a side effect of superselective arterial infusion therapy in a 64-year-old woman. In the first examination, she showed a tumor on the left side of her tongue, measuring 24×17 mm. T1-weighted magnetic resonance imaging (MRI) revealed an enhanced lesion on the left side of the tongue; however, neither an MRI nor a positron emission tomographycomputed tomography showed metastasis to the sentinel lymph nodes or remote organs. Incisional biopsy of the tongue lesion was performed, and the histopathological diagnosis was squamous cell carcinoma. Superselective intra-arterial infusion therapy via the lingual artery was therefore started. On the first day, docetaxel (20 mg/body) and cisplatin (100 mg/m²) were injected by a microcatheter via the lingual artery, followed by 5-fluorouracil (750 mg/m²) injected by drip injection from day two to day five. This cycle of therapy was repeated every four weeks, for a total of three cycles. One week after completing the third cycle, part of the tongue on the left side showed necrosis. The necrotic area did not spread, but the front third of the tongue showed necrotic decay. No effects on pronunciation or deglutition were seen. After three weeks, the area affected by necrosis showed epithelization. The post-treatment course was uneventful, and no signs of recurrence were identified at follow-up after 14 months.

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A hybrid lesion is defined as being a “lesion showing the combined histopathological characteristics of two or more previously recognized odontogenic tumors and/or cysts of different categories.” Adenomatoid Odontogenic Tumor (AOT) is relatively rare, and was previously described as a histological variant of ameloblastoma, but is now recognized as a separate entity by the World Health Organization, representing 3-7% of all odontogenic tumors. AOT is a slow-growing lesion that is thought to arise from odontogenic epithelium because of its predilection for tooth-bearing bone, with varying degrees of inductive changes in connective tissue. It is sometimes referred to as the “two-three tumor” because about two thirds occur in the maxilla, two thirds occur in young women, two thirds are associated with an unerupted tooth, and two thirds of these teeth are canines. Cases of maxillary involvement are more common, usually in the anterior region of the jaw. The present case describes the concomitant occurrence of AOT, dentigerous cyst and CEOT in the anterior portion of the mandible of a 13-year-old male patient. PAS staining was performed for confirmation of amyloid components, followed by Congo Red staining.

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Alternative techniques such as surgically-facilitated orthodontic therapy (SFOT), using corticotomy and single- or multiple-tooth osteotomy to enhance orthodontic tooth movements, are gaining popularity. Presented here is a case report of correction of an ectopically erupted maxillary central incisor using corticotomy-facilitated orthodontic treatment. The results were achieved in comparatively lesser time with good retention and stability.

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