Abstract: To determine the proportion of dental offices in Nagasaki, Japan, that are wheelchair accessible and to identify factors related to the adoption of barrier-free designs within the study area.
Abstract: Supernumerary teeth are generally asymptomatic and may not become visible radiographically until a patient's normal teeth have erupted. Moreover, diagnosing, treating, and following up supernumerary teeth appropriately with radiographic images is important. In this case report, we present radiographic images, including three-dimensional computerized tomography films, of a 13-year-old patient with four nonsyndromic mandibular supernumerary premolars, and the surgical treatment.
Abstract: To examine the dental condition, perceived oral symptoms, and frequency of dental visits among low-income people admitted to Osaka Socio-Medical Center (OMSC) and to compare with Japanese national survey respondents.
Abstract: Many studies have reported an association between diabetes and periodontitis. We analyzed the periodontal status and glycosylated hemoglobin (HbA1c) level in nondiabetic subjects to investigate the relationship between periodontitis and glucose control in nondiabetics.
Abstract: Many elderly patients have various health problems and are susceptible to recurrent fever. We examined the influence of oral health on the febrile status of 271 long-term hospitalized elderly patients over 1 year. In dentate patients, those with > or =20 teeth had a significantly higher risk for fever than those with 1-9 teeth; multivariate logistic regression analysis: odds ratio (OR)=5.44, 95% confidence interval (CI)=1.37-21.66. In edentate patients, those with moderate or much tongue plaque had a significantly higher risk for fever than those with no or slight tongue plaque; multivariate analysis: OR=5.14, 95% CI=1.77-14.88. These results suggest that oral health status related to febrile status differs between dentate and edentate patients in the elderly population.
Abstract: Diabetes and periodontitis are associated with each other. Adipokines, specifically adiponectin and resistin, are secreted from adipocytes and are thought to cause insulin resistance in rodents. Additionally, adiponectin and resistin may play a role in inflammation and immune responses. The aim of this study was to clarify the relationship between serum levels of adipokines and periodontal conditions in elderly Japanese people with and without periodontitis.
Abstract: Resistin and adiponectin, recently discovered adipokines, are secreted from adipose tissue, with postulated opposing functions in insulin resistance and inflammation. More recently, an abundance of resistin was detected in macrophages, which suggests its important role in inflammation. The aim of this study was to clarify circulating serum adipokine levels in women with periodontitis. Thirty-four women with moderate to severe periodontitis and 42 control individuals with healthy gingiva (50- to 59-year-old women) were selected. The serum level of adipokines was analyzed between groups, along with the obesity index, smoking status, and age. Having periodontitis was significantly associated with an increased level of resistin, both in bivariate (OR, 3.0; 95% CI, 1.2-7.6) and multivariate (adjusted OR, 3.1; 95% CI, 1.1-8.6) analyses. The association of periodontitis with a decreased level of adiponectin did not reach statistical significance. It was concluded that an increased serum resistin level in middle-aged Japanese women with periodontitis may affect systemic health.
Abstract: The oral care of hospitalized elderly patients is thought to have a preventive effect on aspiration pneumonia, which is one of the main causes of fever. Although the decreased secretion of saliva is frequently observed in elderly people, no study has examined how a dry oral cavity affects aspiration.
Abstract: A previous study showed the relationship between the intake of dairy products and periodontitis, but the types of dairy products that confer a benefit on periodontal health status have not been determined.
Abstract: Previous epidemiologic studies have suggested that periodontal disease is closely related to obesity and glucose tolerance. As the level of adiponectin, an adipocyte-derived cytokine, in plasma had been reported to decrease in obese and type 2 diabetes patients, we explored the role of adiponectin in the etiology of periodontitis using the D clone of RAW264, a clone that exhibits highly efficient osteoclast formation, to determine whether adiponectin acts as a regulatory molecule in osteoclast formation stimulated by lipopolysaccharide of periodontopathic bacteria. We observed that adiponectin acted as a potent inhibitor of osteoclast formation stimulated by Toll-like receptor 4 (TLR4) ligand and receptor activator of NF-kappaB ligand (RANKL). Because NF-kappaB is an important transcription factor in osteoclast formation, we examined the effect of adiponectin on its transcriptional activity. A luciferase assay showed that adiponectin was able to inhibit the TLR4-mediated NF-kappaB activity in RAW264 cells. In addition, we observed that the cytokine was actually able to inhibit TLR4-mediated expression of the gene for inducible nitric oxide synthase and production of nitric oxide in the cells. These observations strongly suggest that adiponectin may function as a negative regulator of lipopolysaccharide/RANKL-mediated osteoclast formation in periodontal disease.
Abstract: Recent studies have suggested that several systemic conditions--such as obesity, hypertension, hyperlipidemia, and diabetes--are related to periodontitis. The objective of this study was to examine the relationship between periodontitis and 5 components of metabolic syndrome--abdominal obesity, triglyceride level, high-density lipoprotein cholesterol level, blood pressure, and fasting blood sugar level--in 584 Japanese women. In multivariate analyses, persons exhibiting more components of metabolic syndrome had significantly higher odds ratios for a greater pocket depth and clinical attachment loss than did those with no components; the odds ratios for a greater pocket depth and clinical attachment loss of the persons exhibiting 4 or 5 components were 6.6 (95% confidence interval = 2.6-16.4) and 4.2 (95% confidence interval = 1.2-14.8), respectively. These results indicate that metabolic syndrome increases risk of periodontitis, and suggest that people exhibiting several components of metabolic syndrome should be encouraged to undergo a periodontal examination.
Abstract: Previous studies have shown that smoking is a risk factor for periodontitis and that it has a suppressive effect on gingival bleeding. This study examined the relationship between smoking, including past smoking, and periodontal conditions, mainly gingival bleeding, in a community-based health investigation.
Abstract: The treatment of periodontal disease in diabetic patients is reported to have a beneficial effect on their glucose control. A recent study indicated that having deep pockets is significantly associated with past development of glucose intolerance in non-diabetic individuals using an oral glucose tolerance test (OGTT). These findings suggest that periodontal disease is a risk factor for diabetes, although more evidence is needed.
Abstract: The liver is an important organ closely associated with lipid and glucose metabolism. This study was performed to clarify the relationship between periodontitis and hepatic condition in apparently healthy Japanese women. A cross-sectional study was performed on 172 apparently healthy, dentulous Japanese women (20-59 years old) who attended a health promotion program at Fukuoka Health Promotion Center. After multivariate adjustment for age, smoking history and oral hygiene, which were known risk factors for periodontitis, the incidence of periodontitis (deepest probing depth > or =4 mm) in females was significantly increased with elevated serum levels of aspartate aminotransferase (AST, p < 0.01), alanine aminotransferase (ALT, p < 0.01) and cholinesterase (p < 0.001), and an AST-to-ALT ratio of less than one (p = 0.02). Further adjustment for either body mass index (BMI) or percent body fat did not attenuate these relationships. These results suggest that hepatic steatosis is associated with periodontitis in Japanese women.
Abstract: Recent studies have reported a relationship between obesity and periodontal disease. Obesity is the strongest risk factor for type 2 diabetes, which is, in turn, a risk factor for periodontal disease. An oral glucose tolerance test is necessary to diagnose diabetes; however, no study has examined the relationship between obesity and periodontal disease by taking oral glucose tolerance test results into consideration. METHODs: In all, 584 Japanese women aged between 40 and 79 years old, with at least 10 teeth, underwent health examinations. Body mass index, waist-hip ratio, body fat, and oral glucose tolerance test results were used as independent variables with known risk factors for periodontal disease. Mean probing pocket depth and mean attachment loss were used as the dependent variables.
Abstract: Recent studies have shown that adiponectin, an adipocyte-derived cytokine, acts as a potent inhibitor of inflammatory responses. It has been also demonstrated that bacterial and viral signalings in host cells are triggered via Toll-like receptor (TLR) molecules. Therefore, in the present study, we investigated whether globular adiponectin (gAd) would be able to inhibit TLR-mediated nuclear factor-kappaB (NF-kappaB) signaling in mouse macrophages (RAW264). gAd predominantly bound to the AdipoR1 receptor and suppressed TLR-mediated NF-kappaB signaling. gAd-mediated inhibition of TLR-mediated IkappaB phosphorylation and NF-kappaB activation was eliminated by the pretreatment of cycloheximide. Also their inhibitions of gAd were blocked by preincubation of the cells with an antibody against AdipoR1, but not with an antibody against AdipoR2. Taken together, these findings indicate that adiponectin negatively regulates macrophage-like cell response to TLR ligands via an unknown endogenous product(s).
Abstract: Although recent studies suggest a relationship between alcohol consumption and periodontal disease, the dose-response relationship between drinking and the severity of periodontitis is unclear.
Abstract: Recent studies have suggested a relationship between periodontitis and cardiovascular disease (CVD). This study investigated the relationship between periodontitis and electrocardiographic (ECG) abnormalities, which are known predictors of CVD.
Abstract: A TaqMan-based real-time PCR assay was established to quantify the periodontopathic bacteria Tannerella forsythensis and Fusobacterium spp. With this assay, the prevalence and proportion of these bacteria in clinical specimens were evaluated. Our preliminary results suggest a positive colocalization of T. forsythensis and Fusobacterium spp. in periodontal pockets.
Abstract: Treponema denticola has been implicated in periodontitis, and the presence of this organism in periodontal pockets has been investigated. However, qualitative analysis is insufficient for the clinical evaluation of periodontal treatments, and quantification of T. denticola populations is essential for monitoring therapeutic efficacy. Therefore, we developed a quantitative method for T. denticola that uses the TaqMan real-time polymerase chain reaction assay. Using this system, we evaluated the relative and absolute numbers of this organism in saliva and subgingival plaque. Furthermore, we analyzed the relationship between the numbers of T. denticola and pocket depth, and found a significant positive correlation (P < 0.0001) between these parameters. This report demonstrates the broad potential of real-time polymerase chain reaction applications in periodontology.
Abstract: Many studies have examined the presence of Porphyromonas gingivalis in periodontal pockets. However, monitoring the number of bacterial cells is difficult. In this study, we performed quantitative analyses of P. gingivalis to clarify the relationship between the numbers of this organism and periodontal status. Using the TaqMan real-time PCR system, we found a significant positive correlation (P < 0.0001) between the number of P. gingivalis and pocket depth. The slope of the regression line indicated that for every 1-mm increase in pocket depth, the number of P. gingivalis increased 10- fold. There was also a significant reduction (P < 0.01) in the numbers of P. gingivalis before and after treatment. These results suggest that the absolute and relative numbers of P. gingivalis are closely associated with periodontal status, and that quantitative analysis of this organism is important for the evaluation of periodontal therapy.
Abstract: Inflammation is hypothesized to play a significant role in the development of type 2 diabetes; however, reports on clinical inflammatory conditions are limited. Studies have suggested that periodontitis affects glucose control in diabetics. This community-based study examined the relationship between periodontitis and glucose tolerance status, including changes in status. The relationship between periodontal condition and the results of a 75-g oral glucose tolerance test was examined in 961 adults in 1998. Deep pockets (mean pocket depth > 2.0 mm) were significantly associated with impaired glucose tolerance and with diabetes as compared with shallow pockets (< 1.3 mm). In the subgroup with normal glucose tolerance 10 years previously, subjects who subsequently developed impaired glucose tolerance were significantly more likely to have deep pockets. Deep pockets were closely related to current glucose tolerance status and the development of glucose intolerance.
Abstract: Moderate elevation of C-reactive protein (CRP) is thought to predict type 2 diabetes and cardiovascular disease (CVD), both of which are associated with periodontitis. Recent studies indicate that periodontal disease is associated with moderate elevation of CRP; however, the relationship between alveolar bone loss (ABL) and CRP elevation is unclear.
Abstract: The loss of teeth is known to influence the mastication of foods and nutritional status. Therefore, we hypothesize that poor dentition status can impair the systemic health of the aged. To clarify the influence of dentition status on deterioration in physical ability, mental impairment, and mortality, we conducted a six-year prospective cohort study of the institutionalized elderly living in 29 of the 30 institutions for the elderly in Kitakyushu, Japan. Bivariate analysis revealed that worse dentition status at baseline led to significantly worse physical and mental impairment, and higher mortality. In a multiple logistic regression analysis, the physical ability of edentulous subjects without dentures significantly deteriorated compared with that of dentate subjects with 20 or more teeth. The six-year mortality rate of the edentulous subjects without dentures was significantly higher than that of the subjects with 20 or more teeth. Poorer dentition status, especially edentulousness without dentures, may therefore be related to deterioration in the systemic health of the aged.
Abstract: Iodine deficiency is a major determinant of endemic goiter which affects bone growth. The purpose of this study was to clarify the relationship between iodine deficiency and oral health. A cross-sectional survey was carried out on 181 inhabitants aged 17 to 40 years in two villages in an iodine-deficient area in Bali, Indonesia. Thyroid swelling, serum level of thyroid-stimulating hormone, DMFT index, plaque index, gingival index, dietary habits and socioeconomic status were examined. Thirty two subjects (21%) had thyroid swelling considered to be endemic goiter, with the highest prevalence in females aged 21 to 30 years (40-41%). The DMFT, food habits, and socioeconomic status were different between both villages. Multiple regression analysis adjusted for age, sex, and location (village) did not detect any association between DMFT and serum thyroid-stimulating hormone level or thyroid swelling. Further studies will be required to confirm these findings.
Abstract: Upper body obesity, related to visceral fat accumulation, is known to increase the risk of various adult diseases, especially type 2 diabetes and cardiovascular disease. This study was conducted to clarify the relationship between upper body obesity and periodontitis. We studied 643 apparently healthy, dentulous Japanese adults who attended programs at Fukuoka Health Promotion Center. Waist-hip ratio, body-mass index (BMI), and body fat were significant risk indicators for periodontitis after adjustment for known risk factors (p < 0.002). Subjects were divided into four BMI (or body fat) categories. In only the subjects with high waist-hip ratio, higher categories of BMI (or body fat) significantly increased the adjusted risk of periodontitis, compared with subjects with low waist-hip ratios and the lowest category of BMI (or body fat). The reported relationship between cardiovascular disease and periodontitis should be reconsidered, since abdominal adiposity or visceral fat can be related to both diseases.
Abstract: Methyl mercaptan production by oral bacteria is thought to be one of the main causes of oral malodor. We examined the ability of periodontopathic Porphyromonas gingivalis to produce methyl mercaptan from L-methionine and found that the invasive strains W83 and W50 produced large amounts of methyl mercaptan. We cloned and sequenced the mgl gene encoding L-methionine-alpha-deamino-gamma-mercaptomethane-lyase (METase) from P. gingivalis W83. The structural mgl gene consisted of 1,200 bp and encoded a 43.3-kDa protein. To examine the role of methyl mercaptan in the pathogenesis of P. gingivalis, a METase-deficient mutant of P. gingivalis W83 was constructed. The methionine degradation activity and virulence of the mutant (M1217) and the parent strain (W83) in mice were compared. M1217 showed a marked decrease in the formation of methyl mercaptan from L-methionine and decreased virulence compared with the wild-type strain W83. These results suggest that methyl mercaptan not only is one of the sources of oral malodor, but may also play a role in the pathogenicity of P. gingivalis.
Abstract: Since 1984 a weekly supervised fluoride mouthrinsing programme has been implemented for schoolchildren in Hisayama, Japan. Consequently, four years after the start of the programme the DMFT index for 12.5-year-old schoolchildren in Hisayama decreased to a value of less than 3.0. However, since 1992 it has increased. The purpose of this study was to investigate the causes of this increasing prevalence of dental caries since 1992.
Abstract: Powdered semiconductor TiO2 has a photocatalytic bactericidal capacity on some kinds of bacteria, but its mechanism still remains unclear. The mode of its photocatalytic bactericidal action on the mutans group of streptococci was investigated. Powdered TiO2 had a bactericidal capacity on all serotypes of mutans streptococci. Streptococcus sobrinus AHT was mainly used for these experiments. The most effective concentration of TiO2 was about 1 mg ml-1 and, at this concentration, 10(5) colony-forming units of S. sobrinus AHT per millilitre were completely killed within 1 min. In order to search for the mechanism of this effect, a high bacterial cell density (10(9) colony-forming units ml-1) was used in the following studies. "Rapid" leakage of potassium ions from the bacteria occurred parallel to the decrease in cell viability. Protein and RNA were "slowly" released from bacterial cells for a reaction time up to 120 min. The pH of the reaction mixture decreased continuously to 4.5 after 120 min. Co-aggregation of S. sobrinus AHT and powdered TiO2 occurred at high bacterial densities (above 10(8) colony-forming units ml-1). Aggregates gradually decomposed with light irradiation. Transmission electron microscopy of S. sobrinus AHT after photocatalytic action for 60-120 min indicated complete destruction of bacterial cells. From these results, bacterial death appears to be caused by a significant disorder in cell membranes and finally the cell walls were decomposed.
