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1.
Dental floss use among elementary school children and environmental factors; a cross-sectional study
Takahisa Toyama Yumi Furukawa Yuki Hayashi Mami Araki Takashi Nakano Osamu Fukuta 《Pediatric Dental Journal》2019,29(2):78-83
BackgroundThe onset of carious lesions and periodontal disease originates in plaque formed from dental bacteria. Appropriate plaque control is therefore important. Dental floss is one instrument used to control plaque. The influence of guardians is an important factor in whether children use dental floss regularly. However, the use of dental floss among school-age children and the relationship between use and family background has yet to be examined.AimIn this study, we conducted a questionnaire survey to examine rates of dental floss use and other related factors among elementary school children and their guardians.MethodsSurveys were sent to 298 guardians of children in grades 1–6 at an elementary school in Japan and 283 valid responses were received. Statistical analyses were carried out, with child’s use of dental floss as a dependent variable and grade, sex, guardian assistance with child's tooth brushing, frequency of child’s dental check-ups, and guardian's use of dental floss as independent variables.ResultsThe results revealed that 18.4% of children used dental floss compared with 52.7% of guardians, suggesting that the rate of usage among children is much lower than that among guardians. Logistic regression analysis further revealed that guardian's use of dental floss was significantly related to dental floss use among children.ConclusionThe guardian's use of dental floss was associated with dental floss use among their children in this group of Japanese elementary school. 相似文献
2.
Naohiko Aozasa Masaru Hatano Ryosuke Saigusa Kouki Nakamura Takehiro Takahashi Tetsuo Toyama Hayakazu Sumida Zenshiro Tamaki Hisataka Maki Shun Minatsuki Issei Komuro Shinichi Sato Yoshihide Asano 《The Journal of dermatology》2020,47(6):609-614
Endothelial dysfunction is a hallmark of vasculopathy associated with systemic sclerosis (SSc). Reactive hyperemia peripheral arterial tonometry is a rapid and non-invasive technique to assess peripheral microvascular endothelial function by measuring changes in digital pulse volume during reactive hyperemia. Low scores of the reactive hyperemia index (RHI) imply an impaired vasodilatory response and, accordingly, impaired endothelial and vascular health. To investigate the clinical significance of the RHI in SSc patients, RHI values were measured in 43 SSc patients and 10 healthy controls. In diffuse cutaneous SSc (dcSSc) patients, RHI values were significantly decreased compared with healthy controls, and inversely correlated with disease duration. In total SSc patients, there was a significant inverse correlation between RHI values and skin score, and interstitial lung disease was associated with the decrease in RHI values. Among vascular symptoms, the current and past history of digital ulcers was seen more frequently in patients with decreased RHI values than in those with normal RHI values. Although no SSc patients had pulmonary arterial hypertension, an inverse correlation was evident between RHI values and mean pulmonary arterial pressure measured by right heart catheterization. These results indicate that the decrease in RHI values is associated with skin fibrosis, interstitial lung disease, digital ulcers and pulmonary vascular involvement leading to pulmonary arterial hypertension, supporting the canonical idea that endothelial dysfunction is a critical event underlying the development of tissue fibrosis and vascular complications in SSc. 相似文献
3.
Irinoda Y Matsumura Y Kito H Nakano T Toyama T Nakagaki H Tsuchiya T 《Operative dentistry》2000,25(4):274-282
This study was designed to investigate the relationship between the etched depth, penetration of sealants and marginal seal. Sixty unerupted lower first premolars extracted from patients for orthodontic reasons were thoroughly cleaned and stored in an antiseptic Ringer's solution at 4 degrees C. A "window" on the occlusal of 15 of the premolars, including both mesial and distal pits, was developed by painting nail varnish around the border of the occlusal surfaces. Etching was then done with 35% phosphoric acid for 60 seconds to all 60 premolars. Five of the "window" teeth were evaluated by microradiography to determine the etched depth of the superficial and subsurface enamel. Five were prepared for SEM analysis to observe the change of the superficial etched enamel surface. Another five "window" teeth were embedded in epoxy resin and sectioned parallel to the long axis of the tooth through the fissures in order to observe the subsurface depth of the etch by SEM analysis. The other 45 teeth were divided into three groups of 15 teeth each. Fissures of each group of teeth were sealed using Prisma-Shield (LD Caulk), Concise White Sealant (3M Dental Products) or Teethmate A (Kuraray) sealants and stored in water (37 degrees C) for 24 hours. They were then sectioned and demineralized before being examined by a scanning electron microscope. Photographs of secondary electron image (SEI) were done to gradate the resin-infiltrated enamel and resin tags for these sealants. After SEM observation, the 15 samples of each applied sealant were polished to a high gloss again and placed in a silver nitrate solution for 24 hours before being examined under the SEM equipped with a back-scatter electron detector. Data were then analyzed using the Welch and Student t-tests. Results showed that fissured enamel of unerupted human lower first premolars became porous after etching with 35% phosphoric acid. The low viscosity sealant Teethmate A (approximately 260 mPa.s), penetrated fully and formed a resin-infiltrated layer in enamel beyond the etched depth. However, the high viscosity sealants (Prisma-Shield and Concise White Sealant) did not penetrate enough to ensure that the acid-etched enamel was infiltrated sufficiently by the sealant to insure good marginal seals. 相似文献
4.
Koiti Araki Herbert Winnischofer Hélio E.B Viana Marcos M Toyama Fabio M Engelmann Ildemar Mayer André L.B Formiga Henrique E Toma 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2004,562(2):145-152
A novel supramolecular species [MnTPyP{Ru(bipy)2H2O}4](PF6)9 containing four cis-bis(bipyridine)(aqua)ruthenium(II) complexes attached to the peripheral pyridyl groups of meso-tetra(4-pyridyl)porphyrin manganese(III) (MnTPyP) has been synthesized, and employed as the precursor of a rather promising multinuclear oxo-transfer catalyst. This complex forms molecular films by dip coating. Such films are soluble in water, but can be stabilized by exchanging the PF?6 anions by [Fe(CN)6]4? or [Zn–TPPS]4?. They exhibit remarkable electrochemical and electrocatalytic activity, as demonstrated in the oxidation of nitrite ions. In this case, experimental evidence supports the involvement of electrochemically generated [ORuIV]2+ groups in the oxidation reaction, reflecting the characteristic reactivity of high-valence metal–oxo complexes. 相似文献
5.
Ji H Nakagaki H Hayashizaki J Tsuboi S Kato K Toyama A Arai K Thuy TT Ha NT Kameyama Y Kirkham J Robinson C 《Archives of oral biology》2000,45(7):611-615
Calculus deposited on a total of 68 permanent teeth from patients 30-60 years old from Nagoya in Japan and Beijing in China was investigated. An abrasive microsampling method was used to examine the fluoride (F) and magnesium (Mg) distribution, using a fluoride ion-specific electrode and atomic absorption spectrophotometry, respectively. F concentrations decreased from the surface towards the interior of the calculus. Mg concentrations, however, gradually rose towards the innermost surface adjacent to the tooth. In all parts of the depth profiles, the average concentrations of both magnesium and fluoride were higher in the Japanese than in the Chinese calculus. Towards the inner surface of the calculus, F and Mg concentrations were also much higher in the Japanese than in the Chinese group. A greater intake of sea foods and greater use of fluoride dentifrices are possible reasons for the higher F and Mg concentrations in the Japanese individuals. 相似文献
6.
Arai K Kato K Nakagaki H Toyama A Nagai N Noguchi T Kirkham J Robinson C Thuy TT Ha NT 《Caries research》2000,34(3):254-259
Using a novel device capable of generating plaque in vivo on a natural enamel substrate, it has been possible to determine fluoride profiles from the saliva-plaque interface towards the enamel surface. Fluoride profiles in dental plaques tended to fall from the saliva-plaque interface towards the enamel. The device also offered the possibility of examining fluoride distributions after pre-treatment of the enamel with fluoride in vitro. Fluoride profiles were determined in plaque generated in vivo on enamel surfaces, which had been previously treated with a 900-ppm fluoride solution. The results showed the previously reported fall from the plaque surface, but in addition, a further rise towards the enamel surface was seen. The data imply that enamel loaded with fluoride can release some of this fluoride back into the plaque and may act as a fluoride reservoir. 相似文献
7.
Katada T Tsuchimochi M Oda T Sasaki Y Toyama M Katagiri M 《Odontology / the Society of the Nippon Dental University》2004,92(1):77-80
Nodular fasciitis (NF) is a benign reactive lesion of the soft tissues related to the fascia and characterized by fibroblastic proliferation. The most common site is the upper extremities (46%), followed by the head and neck region (20%). In the orofacial region, the lesion typically develops within the subcutaneous structures overlying the angle and inferior border of the mandible and the zygoma. Magnetic resonance imaging (MRI) findings of NF in the orofacial region are almost unreported in the literature. In the present case report, we describe MRI findings of mental NF in a 19-year-old woman. MRI revealed a well-defined, round soft-tissue mass lying on the mentum. On T1-weighted MRI, the lesion was isointense to skeletal muscle; it was hyperintense to skeletal muscle on T2-weighted MRI, and was enhanced by Gd-diethylenetriamine pentaacetic acid (DTPA). Histologic examination revealed abundant myxoid degeneration dispersed in the lesion. The T2-weighted higher heterogeneous signal intensity was likely due to abundant myxoid degeneration or the cellular component of the lesion. A strong bright signal intensity belt appeared in the periphery of the lesion on Gd-DTPA enhancement. This rim enhancement appearred to represent small arterioles and venules that were visible in the peripheral area on histologic examination. 相似文献
8.
Tomohiro Hikata Akio Iwanami Naobumi Hosogane Kota Watanabe Ken Ishii Masaya Nakamura Michihiro Kamata Yoshiaki Toyama Morio Matsumoto 《Journal of orthopaedic science》2014,19(2):223-228
Background
Diabetes mellitus (DM) is reported to be a risk factor for surgical site infection (SSI), which is a serious complication after spinal surgery. The effect of DM on SSI after instrumented spinal surgery remains to be clarified. The aim was to elucidate perioperative risk factors for infection at the surgical site after posterior thoracic and lumbar spinal arthrodesis with instrumentation in patients with DM.Methods
Consecutive patients who underwent posterior instrumented thoracic and lumbar spinal arthrodesis during the years 2005–2011, who could be followed for at least 1 year after surgery, were included. These included 36 patients with DM (19 males and 17 females; mean age 64.3 years). The patients’ medical records were retrospectively reviewed to determine the SSI rate. The characteristics of the DM patients were examined in detail, including the levels of serum glucose and HbA1c, which indicate the level of diabetes control.Results
Patients with DM had a higher rate of SSI (6 of 36 patients, 16.7 %) than patients without DM (10 of 309 patients, 3.2 %). Although the perioperative serum glucose level did not differ between DM patients that did or did not develop SSI, the preoperative HbA1c value was significantly higher in the patients who developed SSI (7.6 %) than in those who did not (6.9 %). SSI developed in 0.0 % of the patients with controlled diabetes (HbA1c <7.0 %) and in 35.3 % of the patients with uncontrolled diabetes (HbA1c ≥7.0 %).Conclusions
DM patients whose blood glucose levels were poorly controlled before surgery were at high risk for SSI. To prevent SSI in DM patients, we recommend lowering the HbA1c to <7.0 % before performing surgery. 相似文献9.
Masaya Nakamura Yuji Nishiwaki Takahiro Ushida Yoshiaki Toyama 《Journal of orthopaedic science》2014,19(2):339-350
Background
An epidemiological survey conducted in Japan in fiscal year 2010 revealed a high prevalence of chronic musculoskeletal pain, low patient satisfaction with treatment, a high incidence of protracted treatment lasting a year or more, and reduced quality of life. To improve the current system for treating chronic musculoskeletal pain, it is important to identify risk factors, including patient characteristics, for developing chronic pain. Thus, we sought to determine the incidence of new chronic pain in the Japanese population, as well as the persistence rate, associated factors, and current state of treatment of chronic pain, by repeating a postal survey in a nationwide representative sample group first surveyed in 2010.Methods
Among 11,507 participants in the 2010 epidemiological survey, 1,717 reported chronic pain and 6,283 reported no chronic pain. A repeat questionnaire, mailed to subjects in these 2 groups in fiscal year 2011, received replies from 85 % of those who reported pain and 76 % of those without pain in 2010.Results
The incidence of new chronic pain was 11.1 %. Risk factors for developing chronic pain included working in a professional, managerial, or clerical/specialist occupation, being female, having a BMI ≥25; currently using alcohol or cigarettes; and having completed an education level of vocational school or higher. Persistent chronic pain was reported by 45.2 % of respondents. Those with severe (VAS score ≥7) and constant lower-back pain lasting more than 5 years had the highest risk of the pain persisting. More than 80 % respondents with persistent chronic pain had a history of treatment, and while about 30 % were still receiving treatment at the time of the survey, the other 50 % had discontinued treatment despite the persistence of pain because of a low degree of satisfaction with treatment.Discussion
We identified risk factors related to the development of new chronic pain and the persistence of chronic pain. Countermeasures to prevent chronic pain could be especially important for the high-risk populations for understanding the pathology of chronic pain. 相似文献10.
Narihito Nagoshi Akio Iwanami Yoshiaki Toyama Masaya Nakamura 《Journal of orthopaedic science》2014,19(3):418-423