Saliva stimulated by chewing gum is often used as a sample in buffering capacity testing. However, cases are observed whereby the collectionof the stimulated saliva from young children, the disabled, and the elderly is difficult, and an investigation to establish a method for saliva collection is considered necessary. Although the testing of the buffering capacity using resting saliva or residual saliva in the oral cavity as samples is considered useful, 1 mL or more of saliva is used in the measurements, and the collection of this sample is seen to be difficult. Accordingly, it is desirable to measure buffering capacity by a small volume of resting saliva. Until now, there have been few epidemiological studies investigating the associationof the buffering capacity with caries prevalence ina large group inorder to verify the efficacy of this parameter for risk assessment on using a small amount of resting saliva. In this research, the usefulness was investigated by means of analyzing the relationship between the buffering capacity for a small volume of resting saliva and DMF. The meanof DMF inthe high buffer capacity group was significantly lower from that inthe moderate buffer capacity group (p<0.05) and the low buffer capacity group (p<0.01). These results suggest that determination of the buffering capacity employing a small amount of resting saliva was useful and that the risk of dental caries could be assessed by measuring the salivary buffering capacity using residual saliva in the mouth as the sample.

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Interleukin-1β (IL-1β) has important roles in the inflammation and connective tissue destruction observed in joint diseases such as rheumatoid arthritis. IL-1β is also a key mediator of intracapsular pathologic conditions of the temporomandibular joint (TMJ),including disk displacement/internal derangement and osteoarthritis. To identify putative IL-1β-responsive genes from arthritic disease tissues, gene expression of IL-1β treated and untreated synovial fibroblasts was measured using DNA microarray, and IL-1β-responsive genes were analyzed with GeneSpring. To measure the expression of 8,793 genes in synovial fibroblasts from five TMJ patients, significant changes between controls and IL-1β-treated cells (p<0.05) were detected in 170 genes; 139 up-regulated genes, and 31 down-regulated genes. In addition, the biological interactions of IL-1β-regulated genes were investigated using Ingenuity Pathway Analysis, and it was found that IL-1β affects the expression of several genes in the NFκB signaling pathway. NFKB1 gene expression increased in synovial fibroblasts by IL-1β treatment. Gene expression of IKBa, TNFAIP3 and TNIP1, which are negative-feedback regulators, were also increased after IL-1βtreatment in synovial fibroblasts. The increase in the expression of these genes was confirmed by real time-PCR analysis. The results suggest that IL-1β-responsive genes play important roles in the progression of inflammation and destruction of joint components.

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Recent studies have shown an association between periodontal disease and cardiovascular disease. We previously reported that Aggregatibacter actinomyctemcomitans（Aa）bacteremia accelerated atherosclerosis in apolipoprotein E-deficient spontaneously hyperlipidemic（Apoe^shl）mice. Atherosclerosis is a chronic inflammatory disease regulated by T lymphocyte subsets. In this study, we investigated whether the functional imbalance between Th17, Th1, and regulatory T（Treg）cells, existed in Aa-challenged Apoe^shl mice. The mice were intravenously treated with live Aa HK1651 or vehicles. Histomorphometric features of atheromatous lesions, IL-17⁺ CD4⁺, IFN-g⁺ CD4⁺, and Foxp3⁺CD4⁺ cell frequencies, serum IL-17, IL-6, TGF-β, IFN-γ, and IL-10 levels, and gene expression of Th17-related molecules were examined. Aa challenge induced a Th17/Th1 shift in Apoe^shl mice. Aa-challenged splenic Th1 and Th17 cells greatly increased in contrast with reduction in Treg cells after their transient increase at 13 weeks. Serum cytokine levels of IL-6 were significantly enhanced during Aa-challenge. Similarly, gene expression of differentiation factors（IL-6, IL-17RA and IL-21）, growth/stabilization factor （IL-23）, and transcription factor（STAT3）involved in the development of Th17 cells, as well as Th1-related IFN-γ were also stimulated in Aa-challenged mice. These results suggest that Th17/Th1/Treg imbalance affect the progression of Aa- accelerated atherosclerosis.

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Objective: Xerostomia, temporomandibular disorder, and periodontal disease are frequently seen in menopausal women. However, few studies have reported the prevalence of oralsymptoms during menopause or the cooperation between doctors at outpatient clinics for women and dentists. The purpose of this study was to investigate the frequency of oral symptoms and the cooperation between doctors at outpatient clinics for women and dentists. Methods: A questionnaire was sent to 380 outpatient clinics for women in Japan. The questionnaire included characteristics for the person completing it, staff structure,cooperation with medicalspecialists, the existence of oralsymptoms, details of these symptoms, cooperation with dentists, and space for free responses. Results: The survey response rate was 57.9% (220 of 380 institutions). Most respondents (81.6%) thought that female sex hormones influenced the mouth, and 79.4% had encountered oralsymptoms. The most frequently encountered symptoms were oral dryness, taste disorder, and burning sensation of the mouth. The necessity of cooperation between doctors and dentists was recognized by 63.1%. Staff that recognised the influence of female hormones on the mouth were significantly more likely than others to acknowledge the importance of cooperation (p<0.01). However, as only half of the staff had referred patients to a dental clinic, it seems possible that patients whose symptoms could have been alleviated by dentists were not appropriately managed. Conclusion: Although oral symptoms can relate to menopause, the cooperation between doctors and dentists is poor. Improved cooperation may relieve not only oral complaints but also systemic menopausal symptoms.

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Aim: For the treatment of polydipsia, medication and occupational therapy are implemented. Since polysipsia canʼt be completely intercepted, patients are isolated or restrained in severe case. Determining the predictive factors of polysipsia may lead to decreasing abnormal water consumption. This study aimed to reveal the influence of subjective oral dryness, salivary volume and other factors including medication on polydipsia in patients with schizophrenia. Methods: Fifty-two patients were divided into two groups: a polydipsia patient (PD) group and a non-polydipsia patient (NPD) group. Their age, medical history, age of onset of schizophrenia, duration of suffering, tobacco, frequency of mouth opening, subjective oral dryness, number of medications, number of xerogenic medications, chlorpromazine (CPZ) equivalent dose, salivary volume and salivary spinability were investigated. Results: The number of total medications was significantly higher than that of the NPD group. Subjective oral dryness of the PD group was rated as ʻsevereʼ compared with the NPD group, and the frequency of mouth opening in the PD group was higher than the NPD group, though there were no significant differences. There was no significant difference in salivary volume and spinability between the two groups. Logisticregression analysis that demonstrated the predictors of polydipsia were tobacco and number of medications. Conclusion: It was shown that the predictors of polydipsia were tobacco and number of medications. The polydipsia may reduce by decreasing medications and quitting tobacco.

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Hospitals are the places where infective agents abound. Medical workers may be contaminated by these nosocomial infective agents, such as methicillin-resistant staphylococci. To better understand the potential role ofmedical staffas a reservoir for circulating pathogenic bacteria and their transmission, we analyzed staphylococcal colonization in the oral cavities ofsix medical staffmembers who work at Nihon University Hospital at Matsudo. Oral samples were obtained by swabbing the oral cavities with sterile cotton swabs, and then the inoculated samples were evaluated using routine bacteriological study methods. Staphylococci were detected in the oral samples ofall ofthe medical staff. Staphylococcus epidermidis was the most predominant species in the oral cavity (75.1%). None ofthe medical staffwere infected with methicillin-resistant Staphylococcus aureus (MRSA), but three ofsix staffmembers possessed methicillin-resistant coagulase-negative staphylococci (MR-CNS). Medical staffmembers are both at risk ofinfection and are a potential source of nosocomial pathogens such as methicillin-resistant staphylococci. As a preventive measure against nosocomial infection, it might be necessary to continuously investigate the frequency of methicillin-resistant staphylococci in the oral cavities of medical staff.

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Selecting the appropriate wire alloys during orthodontic treatment requires knowledge of the biomechanical and clinical applications of various metallic orthodontic wires. Microindentation hardness testing is a convenient means of investigating the mechanical properties of a small volume of materials. The aim of this study was to apply the dynamic micro-indentation method as a simple method for determining the mechanical behavior of orthodontic wire alloys. Moreover, through this method, the effect of the indentation peak load on the mechanical behavior of orthodontic wire alloys was investigated. Four commercially available orthodontic wire alloys (stainless steel, cobalt-chromium-nickel alloy, s-titanium alloy and nickel-titanium alloy) were tested. All specimens were straight and round with a diameter of 0.018-inch. Dynamic hardness and elastic modulus of the orthodontic wire alloys under peak loads of 50, 100 and 1,000 mN were determined using a dynamic ultra-micro-hardness tester fitted with a Berkovich indenter tip. The elastic recovery on the nickel-titanium alloy was higher than on the others on unloading of microindentation load and penetration depth curves. Moreover, for all orthodontic wire alloys,both dynamic hardness and elastic modulus decreased with increasing indentation peak load. Thus, we confirmed that the hardness and elastic modulus of orthodontic wire alloys on micro indentation scales is dependent on the indentation size effect. In conclusion, the dynamic micro-indentation method is a usefultechnique for determining mechanical properties within very small areas on the surface of orthodontic wires without complex sample preparation.

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It is difficult to separate Candida dubliniensis from Candida albicans in clinical specimens,because the phenotypic characteristics of C.dubliniensis are similar to those of C.albicans. In this study, we examined the distribution of C. dubliniensis from denture membrane surfaces and the genotype of C. albicans. Twenty-two subjects provided samples obtained using swabs from the denture membrane surfaces of worn dentures. CHROMagar^TM Candida medium was used for the isolation of Candida spp. Candida spp. were detected in 18 of the 22 subjects, and Candida spp. constituted 0.256% (range: 0~1.41%) of the total cultivable microorganisms. C. dubliniensis was detected in 5 of 18 subjects (27.8%). C. dubliniensis was found in coexistence with C. albicans or C. glabrata. As a result of the classification of C. albicans by genotype analysis, the predominant genotype was found to be A. In conclusion, we found that C. dubliniensis was present in healthy denture-wearing individuals.

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The aim of this studywas to investigate how interleukin (IL)-17 and the receptor activator of nuclear factor kappaB (RANK) ligand (RANKL) contribute to root resorption during orthodontic tooth movement. The first objective was to determine the levels of interleukin-17 (IL-17), soluble RANKL (sRANKL) and osteoprotegerin (OPG) in gingival crevicular fluid (GCF) obtained from a patient with severe root resorption after orthodontic treatment. A second objective was to investigate the effects of IL-17 on the release of sRANKL and OPG from human periodontal ligament (hPDL) cells. Subjects with severe root resorption (>1/3 of original root length) were identified. Control group subjects with no loss of root structure while undergoing orthodontic treatment were also identified. GCF was collected non-invasivelyfrom the mesial and distal sides of each of the four upper incisors using filter paper strips. Eluted GCF was used for analysis by enzyme-linked immunosorbent assay (ELISA). Furthermore, this in vitro studywas performed to examine the effects of IL-17 on RANKL and OPG release from human PDL cells using ELISA. Concentrations of IL-17, sRANKL, sRANKL/OPG ratio in GCF were significantlyhigher in subjects with severe root resorption than in those with no resorption. In the in vitro study,IL-17 increased the release of sRANKL, and decreased that of OPG from hPDL cells in a time- and dose-dependent manner. These results suggest that IL-17 stimulates orthodonticallyinduced inflammatoryroot resorption (OIIRR) via production of RANKL in PDL.

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Staphylococci are common residents of the nasal flora. As the nasal and oral cavities are anatomicallyjoined at the pharynx, these organisms are generallybelieved to pass into the mouth consistently. Staphylococci are thus transient residents in the oral cavity. In our previous studies, although Staphylococcus epidermidis was most predominant in both nasal and oral cavities, the distribution of other Staphylococcus species showed diversityin the nasal and oral cavities. Our previous results indicate that the origins of nasal and oral staphylococci are not identical. To investigate the connection between staphylococci and the nasal and oral cavities, the homology of genotypes of Staphylococcus species using arbitrarilyprimed polymerase chain reaction (AP-PCR) was compared. Staphylococcus isolates from the nasal and oral cavities of the same subject showed different genotypes on AP-PCR using OPA-03 primer. These results indicate that staphylococci in the oral cavity are not derived from those in the nasal cavity, and do not move between the nasal and oral cavities.

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Intramuscular hemangiomas are uncommon benign tumors in the head and neck region. The masseter muscle is the most commonly involved muscle in the orofacial region, but simultaneous involvement of both the mentalis and masseter muscles has not yet been reported. Preoperative diagnosis of such lesions is difficult because of the rarity of such tumors, their deep intramuscular location, and their unfamiliar clinical presentation. A case of intramuscular hemangioma of the masseter and mentalis muscles in a young Indian male patient is presented with a review of the role of various imaging modalities in such tumors.

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