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21.
We hypothesized that one mechanism underlying advanced periodontal disease in diabetes may involve oxidant stress in the gingiva, induced by the effects of Advanced Glycation Endproducts (AGEs), the irreversible products of non-enzymatic glycation and oxidation of proteins and lipids which accumulate in diabetic plasma and tissue. Infusion of AGE albumin, a prototypic ligand, into mice resulted in increased generation of thiobarbituric acid reactive substances (TBARS) compared with infusion of non-glycated albumin in the gingiva, as well as in the lung, kidney and brain. Pretreatment of the animals with the antioxidants probucol or N-acetylcysteine (NAC) prevented the generation of TBARS in the gingiva. Affinity-purified antibody to AGEs demonstrated increased immunoreactivity for AGEs in the vasculature and connective tissues of the gingiva in streptozotocin-induced diabetic mice compared to non-diabetic controls. Increased immunoreactivity for AGEs was also demonstrated in the gingiva of diabetic humans compared with non-diabetic individuals via immuno-histochemistry and ELISA. Consistent with these data, immunohistochemistry for heme oxygenase-1, a marker of enhanced oxidant stress, was increased in the gingival vasculature of diabetic mice and humans compared with non-diabetic controls. These data suggest that AGEs present in diabetic gingiva may be associated with a state of enhanced oxidant stress, a potential mechanism for accelerated tissue injury.  相似文献   
22.
The aim of this study was to compare detection of non-cavitated approximal caries lesions in images from seven solid-state intraoral digital receptors, with particular focus on two task-specific enhancement filters. One hundred and sixty approximal non-cavitated surfaces were radiographed under standardized conditions using the following seven intraoral solid-state digital receptors: two CMOS systems, Schick CDR-APS, and Kodak RVGui; and five CCD systems: Visualix, VistaRay, Dixi2, Sidexis, and Dr. Suni Plus. The Kodak RVGui digital images were captured with two task-specific, predefined enhancement filters ("dento-enamel" and "periodontal"). Eight observers examined the digital images for the presence or absence of approximal carious lesions. The teeth were subsequently sectioned for histological analysis, which served as the "gold standard" for the radiographic examination and allowed for a calculation of sensitivity, specificity, and overall accuracy. Both RVG modalities obtained the highest sensitivity values, which were significantly higher than with Visualix, Sidexis, and VistaRay images (all P 0.05).  相似文献   
23.

Background

(i) to describe oral health counselling in Norway to parents with infants and toddlers, ii) to assess existing collaboration and routines in oral health matters between nurses and personnel in the PDS, iii) to evaluate to what extent oral health was integrated in the basic educational curriculum of public health nurses.

Methods

This study was based on two separate surveys: the sample of Study I was 98 randomly selected child health clinics. A questionnaire covering oral health promotion counselling of parents with young children was returned by 259 nurses. Study II was a telephone survey addressing teachers of public health nurses at the eight educational institutions in Norway.

Results

The response rate in Study I was 45%. Nutrition (breast feeding, diet) was the health subject most often prioritized in the counselling targeting parents of young children (by 60% of the nurses). Oral health was not among the first priority counselling subjects. The subject was seldom spontaneously mentioned by parents. Seventy percent of respondents reported (agreed or totally agreed) that they managed to provide information parents needed and 72% believed that the information they gave influenced parents' health behaviours. Seven nurses (5.2%) responded that they agreed with the statement that the information they gave only slightly influenced parents' health behaviour. Lack of time was mentioned as being a problem. Approximately half of the nurses (48%) had regular contact with the PDS for the 0-3 year-old children, but only a quarter of the nurses claimed that children's teeth were routinely examined at the child clinics. Some forms of previously established contact with the PDS enhanced the likelihood of nurses' referrals. Oral health was a minor part of the educational curriculum for public health nurses; at three institutions, the subject was totally absent.

Conclusion

Collaboration between nurses and the PDS in Norway could be improved. Oral health should have a bigger place in the basic educational curriculum.  相似文献   
24.
25.
BACKGROUND: The significance of serum concentrations of various antibodies and cytokines in the pathogenesis of early-onset periodontitis (EOP) is not well understood. Recent reports suggest differences between young blacks and whites in certain humoral responses, regardless of periodontal status. This study was undertaken to compare the serum concentrations of IgG, IgA, IgM, and IL-1beta in EOP subjects with that of healthy controls, and to study the effect of race on these levels. MATERIAL AND METHODS: This case-control study included 228 individuals, 19-25 years old who were selected from a larger population examined in the National Survey of Oral Health of United States Children in 1986/1987. The subjects were classified by their EOP status and they included 166 subjects with EOP and 62 healthy controls. Blood samples were used to assess the serum concentrations of IgG, IgM, IgA, IgG subclass, and IL-1beta. RESULTS: The serum concentrations of IgG, IgG subclasses, IgA, and IgM in blacks were not significantly different in the generalized, localized and incidental EOP groups as compared to the healthy controls. The serum IL-1beta concentration was slightly and uniformly lower in the EOP groups than in the control group, although not statistically significant. Blacks had significantly higher serum concentrations of total IgG, and of IgG1, IgG2 and IgG3 than whites and Hispanics. Hispanics had significantly higher serum concentrations of IgM and IgG4 than whites and blacks. Hispanics also had a significantly higher serum concentration of IL-1beta than blacks. CONCLUSIONS: Total antibody response in blacks is not associated with EOP classification. Race has a significant effect on serum antibody concentrations irrespective of disease classification, with blacks having significantly higher serum concentrations of IgG1, IgG2 and IgG3 than whites and Hispanics.  相似文献   
26.
A case of an unusual number of supernumerary teeth is reported because patients who present with this symptom may be suffering from Gardner's syndrome or cleidocranial dysostosis.  相似文献   
27.
Steroid-induced anterior open bite. Case report   总被引:1,自引:0,他引:1  
A young man presented with an increasing anterior open bite due to severe erosion and eventual collapse of the mandibular condyles. He had been undergoing immunosuppressive treatment, including high dose prednisolone, to treat the rejection of his renal transplant originally, and subsequently in connection with his mitral valve replacement following infective endocarditis. He also suffered severe secondary hyperparathyroid bone disease. A search of the English language literature failed to find a similar case.  相似文献   
28.
Dentistry is undergoing significant changes with need for the dentist to manage a larger body of knowledge and information. There will be increasing reliance on electronic information systems in education, research, and dental practice. Dental informatics is concerned with computer and information science and technology and communications. Goals, that could be adopted for Australia, were proposed in the USA in 1989. Specific action steps that could meet those goals are proposed for Australia.  相似文献   
29.
It is generally accepted that in the treatment of Class II, 1 malocclusion classical activators may tip the upper incisors considerably. In comparison, in the cases described, an even better torque control was obtained. It has been our clinical experience that with the modified Teuscher activator it is possible to control upper incisor inclination and in some cases it is even possible to induce active palatal root torque. The appliance is relatively comfortable with good vertical retention even without headgear.  相似文献   
30.
There is little knowledge of the number or the work characteristics of dental hygienists outside the private-practice setting. This survey was conducted to determine the percentage of hygienists practicing in nontraditional (nonprivate-practice) settings and the types of settings in which they are employed. Mail questionnaires were returned from a total of 21,847 (56.9%) of the hygienists in the survey sample. The percentage of active hygienists practicing in nontraditional settings was 11.8. Dental or dental hygiene schools, and government and nongovernment-supported clinics were the most frequent nontraditional practice settings. State supervision requirements were found to be associated significantly with the prevalence of nontraditional hygiene practice.  相似文献   
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