Necrotizing sialometaplasia (NSM), a benign tumor-like lesion of the salivary glands, often resembles a malignant tumor in terms of clinical and histopathological features. In general pathology, metaplasia results from a kind of progressive change after chronic abnormal stimuli, and NSMis thought to arise after ischemic necrosis. However, the nature and pathogenesis of NSMremain unclear. The purpose of the present study was to investigate the morphological characteristics of metaplastic change in NSMby histopathological and immunohistochemical analyses using primary antibodies for cytokeratins (CKs) and MIB1.Positive immunohistochemical reactivities for CK13 and MIB-1 staining in the squamous metaplasia of NSMwere observed. Positive reactivity for CK13 was observed in prickle cells of the stratified squamous epithelium. The mean MIB-1 index was 6.0%. These results suggest that duct epithelial cells are responsible for metaplasia in NSM, because ducts in the palatal glands showed stratified squamous-like epithelium near areas of NSMand immunohistochemical findings resembled either salivary glands or oral mucosae covered with the lesion.

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Small non-coding microRNAs (miRNAs) regulate cellular and developmental processes through the modulation oftarget gene expression and/or protein synthesis. miRNAs are expressed in a cell-specific manner. Human mesenchymal bone marrow stem cells (hMSC) and human dental follicle cells (hDFC) can undergo multilineage differentiation into various connective tissue cell types, and may therefore be utilized for regeneration in cell therapy. To elucidate the molecular differences that underlie the more primitive characteristics ofhMSC and hDFC, we performed a comprehensive comparative analysis ofthe miRNA and mRNA expression profiles ofhMSC and hDFC using a two-fold change in the normalized intensity of expression as a cut-off to determine differences in expression. In hMSC, 37 were more highly expressed, while 32 miRNAs more highly expressed in hDFC. hMSC expressed high levels ofmiR-196a, -196b, and miR-10a, -10b, which target several homeobox (HOX) genes associated with the patterning ofthe vertebrate axial skeleton. hMSC, but not hDFC, expressed high mRNA levels ofHOX genes. In contrast, miR-199b, which is expressed in tooth germ, as well as the forkhead box O1 (FOXO1) gene, a target ofmiR-1271, were more highly expressed in DFC than in hMSC. The FOXO1 transcription factor plays a role in tooth development and regulates biomineralization. These miRNAs showed specific expression in tissues from which stem cells originate, suggesting that they influence the characteristic mRNA expression of these tissues. These data suggest that analysis of miRNA-mRNA expression profiles is useful for characterization of specific tissue types and cell-specific markers.

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Rheumatoid arthritis (RA) is a systemic autoimmune disease that involves inflammation and joint pain and causes bone resorption. Irradiation with light-emitting diodes (LEDs) is being evaluated for the treatment of RA, but the underlying molecular mechanisms are unclear. To determine whether anti-inflammatory effects are provided, LED irradiation was provided for rats with collagen-induced RA (CIA), and total RNA was isolated from the synovial tissues of CIA rat joints. Gene expression profiles were then monitored by DNA microarray. LED irradiation decreased the swelling in CIA rat knee joints. DNA microarray analysis demonstrated that expression of many genes was altered in RA, including increased MMP3 mRNA levels, while MMP3 mRNA levels were reduced by LED irradiation. These reductions in MMP3 mRNA levels by LED irradiation were confirmed by RT-PCR and real-time PCR. Immunohistochemical analysis demonstrated strong staining for MMP3 in the CIA group, and LED irradiation significantly reduced this staining. Clinical features of reduced swelling in CIA knee joints suggest that LED irradiation might be useful as RA therapy. Since MMP3 has been identified as an important factor in the pathogenesis of RA, reducing MMP3 expression by LED irradiation might offer an important mechanism for reducing inflammation in RA.

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The South Pacific Medical Team, a voluntary group organized by Japanese dentists, has worked to improve oral health in the Kingdom of Tonga since 1998. Its main activity is the planning and administration of a school-based program known as the MaliMali Program.The MaliMali Program has been promoted by a Tongan team for preventive dentistry from the Dental Office of the Ministry of Health. In the present study, we describe the results of the MaliMali Program and consider its effects from 1998 to 2009.The MaliMali Program consists of the following three main programs, plus additional activities: an education program for kindergarten and primary school children to prevent caries (including leaflet distribution, lectures, and guidance about eating between meals); a program teaching children about the proper use of toothbrushes and fluoride toothpaste;and a program providing children with fluoride mouth rinse. In the latter program, 7-10mL of a 0.2% NaF solution was given to children in primary school once a week; 5mL of a 0.05% NaF solution (Miranol^®) was given to children in kindergarten once a day. We investigated oral health habits (dietary habits in 2001, toothbrushing habits in 2008), oral conditions (prevalence of dental caries in 2001 and 2007, effectiveness of fluoride mouth rinse for prevention of caries in 2008), and gingivitis and gingival bleeding (in 2003). In 2008, 34 kindergartens, 101 primary schools (75.4% of all schools in Tonga), and 14,442 children in total participated in the MaliMali Program. In 2008, all children reported brushing their teeth at least once a day. The mean decayed/missing/filled teeth (DMFT) score DMFT and the decayed/missing/filled (DMF) person rate had decreased significantly in 2007 compared to 2001. In 2008, we examined whether fluoride mouth rinse is effective for the prevention of caries and found that fluoride mouth rinse significantly decreased the mean DMFT score. In 2003, 52.0% of children had gingivitis and 20.6% had gingival bleeding.The MaliMali Program is universally accepted in the Kingdom of Tonga. It has helped to establish childrenʼs toothbrushing habits and the application of fluoride has decreased the incidence of caries.

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The purpose of this study was to evaluate the change of vital signs and adverse reactions with intravenous nonionic iodine contrast media using computed tomography (CT).Seventy-six patients who received contrast enhanced CT with nonionic iodine were studied. Systolic and diastolic arterial blood pressure, pulse rate and arterial blood oxygen saturation were monitored. The mean values of change were +0.36±6.18mmHg, −0.24±6.36mmHg, +4.95±6.63bpm and −0.17±1.22%, corresponding to systolic and diastolic arterial blood pressure, pulse rate and arterial blood oxygen saturation, respectively. Only one of 76 patients (1.3%) had nausea with rising of pulse rate and the infusion was stopped immediately. After that, pulse rate returned to nearly normal and nausea was disappeared. In conclusion, monitoring vital signs is very useful method for early detection of the accidental adverse reactions.

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Constructive operation of jaw bone for implant treatment becomes complex depending on the defect area of the bone getting larger and giving patients pain. We encountered a case of implant treatment after operation of ossifying fibroma in a 28-year-old Japanese woman.One-piece of the implant used in the treatment was able to restore the mastication and aesthetical problem of the second premolar and first molar. In addition, the atelocollagen sponge and barrier membrane used together in the treatment also improved the prognosis of the implant treatment.

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The aim of this study was to investigate the amount of external apical root resorption(EARR) and the release of interleukin (IL)-1 beta in the gingival crevicular fluid (GCF) in subjects treated with a low-force low-friction system.Sixty patients were assigned to two groups of thirty patients each: one group received treatment with self-ligating brackets and the other received conventional ligated edgewise brackets. All patients were treated with extraction of the maxillary first premolars. The EARR of the maxillary central incisors was evaluated on the periapical radiographs and cephalograms, taken before and after orthodontic treatment. The GCF was also collected non-invasively from the mesial and distal sides of central incisors using filter paper strips before and after orthodontic treatment. Enzyme-linked immunosorbent assay (ELISA) kits were used to determine the IL-1 beta levels in the GCF samples.A significant difference was found in the amount of EARR between the patients with selfligating brackets and conventional brackets. The mean amount of EARR was significantly lower for self-ligating brackets than the conventional brackets (p<0.05). The GCF levels of IL-1 beta for the patients with the self-ligating brackets application were significantly lower than for those with the conventional brackets (p<0.05).These results show that the mean amount of EARR and the GCF levels of IL-1 beta are significantly lower in patients treated using low-force low-friction appliances than with the conventional brackets. Therefore, self-ligating brackets may be a useful system for reducing inflammation and EARR.

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Many variations in crown morphology are seen. The most common among these are accessory cusps present on the crown surface. These accessory cusps most commonly occur on the molars (cusp of Carabelli), incisors (Talonʼs cusp) and premolars (Leongʼspremolar). To date, the dental literature has reported very few cases with a morphological variation on the mesio-buccal cusp of the deciduous molars. We herein present 2 cases where we observed an extra cusp on the buccal surface of the deciduous maxillary first molar adjacent to the mesio-buccal cusp. A groove separates this cusp from the mesiobuccal cusp. This cusp was present bilaterally in one case and unilaterally in the other.Presence of this anomaly may necessitate modification of treatment plans and treatment procedures in children.

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Mucosal allergies represent a growing problem and often go undiagnosed by health professionals. The prevalence of mucosal allergies due to drugs routinely prescribed in dental practice appears to be increasing. Ingestion of certain drugs by individuals with idiosyncratic reactions or intolerance may result in allergic manifestations referred to as stomatitis medicamentosa. The clinical features may vary from a burning sensation to ulcerative lesions in the oral cavity. These lesions resolve with discontinuation of the causative agent. However, antihistamines and steroids are the drugs of choice in severe cases. We describe herein the case of a 45-year-old woman with an allergic reaction to an Over- the- Counter drug, treated in the Department of Oral Medicine & Radiology at D. A.Pandu Memorial R. V. Dental College, Bangalore, India. The pathogenesis, clinical features, diagnosis and treatment are discussed.

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Langerhans cell histiocytosis (LCH), a monoclonal disease of histiocytes, may involve several organ systems but rarely involves the maxillary sinus as a primary site. This report presents an extremely rare case of LCH of the maxillary jaw in an 11-month-old girl. An incisional biopsy for a maxillary lesion was performed, and a histopathological diagnosis of LCH was established. The histopathological examination revealed the proliferation of histiocytes with an infiltration of eosinophils. Histiocytes were positive for S-100 and CD68(KPI). The patient subsequently underwent chemotherapy with the resolution of LCH in the maxillary jaw, and has continued to show partial response as of 1 year after chemotherapy.

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The diagnosis of a dysplastic pre-malignant or malignant lesion of the oral mucosa cannot be based solely on clinical findings. Therefore, histologic evaluation of a representative biopsy specimen is necessary. The choice for the site of biopsy, however, has so far remained a subjective choice that sometimes raises doubts about its representativeness. No simple and reliable method is yet available for selecting the most appropriate site for biopsy. Intra-oral microscopy (oral application of the colposcopy technique) of mucosal lesions seems to offer advantages in selecting the sites most representative of dysplastic changes for biopsy beyond routine clinical examination alone. This article highlights the application of intra-oral microscopy of the oral mucosa in the diagnosis of various oral premalignant lesions and conditions and its advantage in selecting the most representative biopsy site for the confirmation of the histopathological diagnosis of dysplasia.

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