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991.
BACKGROUND: Low-calorie diets are commonplace for reducing body weight. However, no information is available on the effects of a reduced-calorie diet on periodontal inflammation and disease. The purpose of this study was to evaluate the clinical effects of a long-term calorie-restriction (CR) diet on periodontitis in an animal model of periodontitis. METHODS: Periodontitis was induced in 55 young, healthy, adult rhesus monkeys (Macaca mulatta) by tying 2.0 silk ligatures at the gingival margins of maxillary premolar/molar teeth. Animals on a CR diet (30% CR; N = 23) were compared to ad libitum diet controls (N = 32). Clinical measures, including the plaque index (PI), probing depth (PD), clinical attachment level (CAL), modified gingival index (GI), and bleeding on probing (BOP) were recorded at baseline and 1, 2, and 3 months after ligature placement. RESULTS: Significant effects of CR were observed on the development of inflammation and the progression of periodontal destruction in this model. Compared to controls, CR resulted in a significant reduction in ligature-induced GI (P <0.0001), BOP (P <0.0015), PD (P <0.0016), and CAL (P <0.0038). Periodontal destruction, as measured by CAL, progressed significantly more slowly in the CR animals than in the controls (P <0.001). CONCLUSIONS: These clinical findings are consistent with available evidence that CR has anti-inflammatory effects. Moreover, these experimental findings are the first observations, to the best of our knowledge, that CR dampens the inflammatory response and reduces active periodontal breakdown associated with an acute microbial challenge.  相似文献   
992.
Migration of leukocytes to inflammation sites through vascular endothelium is controlled by the interactions of adhesion molecules expressed on both endothelial cells and leukocytes, most of which are already covered by cluster of differentiation (CD) codes. We examined the expression of a variety of endothelial cell adhesion molecules in human dental pulp vasculature to obtain further evidence on the tissue distribution and function of these molecules by using an indirect immunoperoxidase technique. We obtained the pulp tissue samples from teeth extracted due to orthodontic reasons as controls and compared with those extracted due to chronic periodontitis. In all samples, both CD31 and CD146 were expressed by arterial, venous, and capillary endothelia. There was no significant difference between the staining intensity of normal and inflamed pulp tissues. CD102 expression on the endothelium was significantly stronger in chronic periodontitis pulp samples. CD106, CD62-E, CD62-P, CD105, and CD54 were variably expressed in control and chronic periodontitis groups. Our results indicate that CD102 represents the major endothelial cell adhesion molecule probably involved in the inflammatory reactions in chronic periodontitis.  相似文献   
993.
The 3 human salivary cystatins S, SA and SN are multifunctional proteins that possess a cysteine protease inhibitory property, but their ability to act as such is very different (SN > SA > S). One form, S, also appears to possess antibacterial properties towards the bacterium Porphyromonas gingivalis, often associated with periodontal diseases. In this study we measured the total cystatin inhibitory activity and the levels of each salivary cystatin in the whole saliva of 8 periodontally diseased patients and 2 groups of control subjects (n = 6 and n = 10). The total cystatin inhibitory activity and the total salivary cystatin concentration in the periodontally diseased patients were found to be lower than the controls (p < or = 0.005). The concentration of S was depleted to levels that would not allow it to be an effective antibacterial agent, and the concentration of SA, although depleted in some cases, was still present at sufficient levels to allow it to act as an effective physiological inhibitor of cathepsin L. The concentration of cystatin SN was also depleted in the periodontally diseased patients, but was still present in sufficient quantities to act as an effective physiological cysteine protease inhibitor of cathepsins H and L. In comparison, the concentration of all 3 salivary cystatins in the control subjects were sufficient to enable these proteins to be both effective physiological cysteine protease inhibitors and antibacterial agents.  相似文献   
994.
A bstract — Hepatitis B is becoming increasingly common in the community. Carriers are generally difficult to identify in dental practice, and therefore preventing transmission of the disease depends primarily on sound general clinical hygiene.  相似文献   
995.
The present state of education in forensic odontology is surveyed. Courses in the subject within dental schools are directed mainly towards dental students (lectures, seminars, demonstrations), but also towards chairside assistants, dental hygienists and laboratory technicians. Extra-mural postgraduate education is directed towards private practitioners, but includes community dental health officers and colleagues serving in the defence forces; the question of 'qualification' is discussed. Finally, a wide range of non-dental personnel is approached (medical and law students, community health officers, forensic medical experts, police technicians etc.). The authors concur that independent departments of forensic odontology are now needed at all major dental schools; only here can the manpower and the facilities be developed to cope with this wide spectrum of education, and only here can recognized academic positions be ensured for those who--together with other specialists--must handle an increasing extra-mural case load, from which all material for education and research is subsequently to be derived.  相似文献   
996.
A bstract — A stratified sample of 1,588 of the 3,990 first year students at The University of Sydney responded to a questionnaire on the utilization of dental services as set out in the World Health Organization's Combined Oral Health and Treatment Assessment Form. More than 70 per cent had obtained dental care within the previous 12 months and 59 per cent of these visited for a check-up. The most common reasons for not obtaining dental care was given as "nothing wrong, or there was no reason for going". Sixty-five per cent indicated that they considered there was nothing wrong with their teeth, gums, or mouth. Twenty-five per cent wanted advice or treatment mostly for examination or cleaning. Comparison of results was made between Faculties and other community studies.  相似文献   
997.
A number of metallic elements were added singly and in combination to a simple nickel-chromium alloy. The effect of alloy composition was determined by radiographic and metallographic examination.  相似文献   
998.
A bstract — Arthrography is useful in selecting those patients with severe dysfunction of the temporomandibular joint who would benefit from surgery. Plain films are usually unrewarding in the diagnosis of soft tissue abnormalities of the joint. Three cases are presented, illustrating the most common problems encountered and diagnosed by arthrography.  相似文献   
999.
A bstract — An extensive programme was begun in 1977 to assess annually the dental health of school children aged four to thirteen years examined by the school dental services in each State and Territory.
In the period 1977 to 1982, the number of DIMF teeth per child declined by 41.4 per cent while the oral hygiene index was reduced by 21 per cent. Significant factors in addition to fluoridated water and fluoridated dentifrices have contributed to the decline in the prevalence of dental caries, however, the current data indicate that the decline in the annual increment of dental caries has ceased.  相似文献   
1000.
OBJECTIVES: Increasing evidence suggests a strong causal link between smoking and periodontitis. The goal of this study was to impute how the secular changes in smoking prevalence during the 20th century impacted the advanced periodontitis incidence in the US. METHODS: Epidemiological analyses based on US prevalence data of advanced periodontitis and smoking, and predictions of future smoking prevalence. RESULTS: Assuming other risk factors for periodontitis remained constant, we estimated that the incidence of advanced periodontitis decreased by 31% between 1955 and 2000. The changes in smoking habits, and consequently the changes in periodontitis incidence, depended strongly on education and gender. Between 1966 and 1998, we estimated a 43% decreased periodontitis incidence among college-educated individuals versus only an 8% decrease among individuals with less than a high school education. Between 1955 and 1999, we estimated a 41% decrease among males versus a 14% decrease among females. By the year 2020, the incidence of advanced periodontitis may decrease 43% from its level in 1955. CONCLUSIONS: A periodontitis epidemic fueled by smoking remained hidden for most of the 20th century. Because this epidemic was hidden, it distorted our understanding of the treatment and etiology of periodontitis. The socioeconomic polarization of this epidemic will dictate alterations in patterns of periodontal care.  相似文献   
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