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The effects of dental disease on the population are difficult to describe to the lay public in terms which that public will appreciate. An attempt has been made to quantify the impairment of the quality of life which results from uncontrolled dental disease. Studies indicated that each person could have three to four days of dental pain a year which could be equivalent to 200 million days of toothache per year in the United Kingdom. Only 15 per cent of those who had toothache did seek dental advice for it. This represented a waste and an impairment in the quality of life. It is proposed that estimates of days of dental pain could prove an index of the quality of life of a population.  相似文献   
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Seventy-two female New Zealand white rabbits were divided into six groups and killed with Nembutal at 17.0, 17.5, 18.0, 18.5, 19.0 and 19.5 days postconception. The foetuses were removed; the palates, maxilla, mandibles and tongues were dissected from each foetus, weighed and pooled; DNA, RNA and protein were determined in each pooled sample. The results showed three distinct patterns of development. The mandible and maxilla showed similar developmental patterns, while the palate and tongue each showed their own distinct pattern. The palate showed a remarkable rise in protein/DNA at day 18.0, the time corresponding to palatal closure in our rabbits. Further such studies may elucidate the role that relative growth rates of these tissues plays in the aetiology of cleft palate.  相似文献   
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BACKGROUND: It has been suggested that locally produced immunoglobulin (Ig)A could be more protective than IgG and that there could be a relationship between crevicular fluid-specific IgA levels and the onset of periodontal disease. This study was designed to investigate this hypothesis regarding specific immune responses towards 4 plaque anaerobes in gingival crevicular fluid and saliva from patients with periodontopathies and controls. METHODS: Gingival crevicular fluid (GCF) and whole saliva were collected from 35 adults with periodontitis and 24 periodontally healthy adults (controls). Antigens were extracted from Actinomyces actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, and Fusobacterium nucleatum and used to set up specific enzyme-linked immunosorbent assay (ELISA) tests to assess IgA and IgG levels to these microorganisms in the fluids collected. RESULTS: The crevicular fluid of periodontitis patients contained significantly higher levels of IgG to the 4 microorganisms tested than that of controls (P < 10(-6) for all comparisons). IgA levels to the 4 bacteria were statistically significantly much higher in control crevicular fluid (P < 10(-7) for all comparisons). Controls also had statistically significantly higher levels of specific salivary IgA than patients (P < 0.02 for all comparisons). CONCLUSIONS: These data support the potentially protective role of specific IgA directed to oral microorganisms involved in the onset and development of periodontal disease.  相似文献   
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A rapidly growing postnatal animal model was used to study changes in the calcified tissue of the mandibular condyle during altered muscle function. A maxillary occlusal splint was designed to shift the mandible laterally (left) during closure. Groups of 5 Wistar rats were killed at 5, 9, 15, 21, 30, and 40 weeks (n = 30), with an equal number of controls. The experimental animals developed shorter, asymmetrical mandibles compared with the control animals. The left condyle became larger and thicker than the right condyle. Microcomputed tomography assessment of the left and right condylar trabecular bone indicated that both had less bone volume than the control condyle. The right masseter muscle significantly lost fiber size and type IIA oxidative fibers, suggesting that the right masseter muscle was used with less tension development. In contrast, the left masseter maintained its fiber size and was similar to the control masseter fiber diameters. Comparison in the sequence of changes indicated that the morphologic changes occurred first in the ramus (age, 5 weeks), before the corpus (age, 15 weeks), and before changes in masseter fiber size and composition (age, 9 weeks). This study showed that both the mandible and the condyle modified their shape and size, as well as the trabecular bone of the condyle, during shifting of the mandible to one side as it closed.  相似文献   
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Dentists, like other health care workers, make an overt effort to protect themselves and their employees from infectious agents present in the body fluids of their patients. Of special concern are treatment-generated infectious waste materials, such as sharps. Sharps are items such as needles, sutures, scalpel blades, or broken glass which are capable of puncturing, cutting, or abrading tissue. Needles can cause occupational transmission of hepatitis B and AIDS. This article presents methods to safety store, treat, and dispose of sharps. All suggested procedures comply with current Indiana law, CDC guidelines, and EPA and OSHA regulations.  相似文献   
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