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It has been reported that little diagnostic information concerning periodontal conditions is entered in patient records of general practitioners, but actual rates for such chart entries are unknown. Records of regular patients, seen at least annually, were randomly selected from the offices of 36 general practitioners in two North Carolina counties. In each office 80 records were selected for audit. After adjustment, the final sample consisted of 2488 audited records. Entries noting the presence or absence of 14 diagnostic conditions were identified for the five previous years and for the patient's most recent examination. The presence of a periodontal diagnosis or periodontal treatment plan was noted. The number of radiographic sets exposed in the previous five years and the age of the most recent set were determined for complete series/panoramic films and for bitewings. Across practices, the most frequent notations (20.5% within the past five years) concerned the presence of probing depths and calculus. Gingival bleeding (13%) and plaque (12%) were noted less frequently. A periodontal diagnosis was recorded in only 16.3% of the records. Annualized rates for radiographic sets were 0.09 for complete series/panoramic films and 0.50 for bitewings. These data suggest that, except for radiographs, the majority of patient records do not contain sufficient diagnostic information to describe patients' periodontal health.  相似文献   
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The aim of this study was to investigate the effect on subgingival plaque of a simplified oral hygiene regime consisting of instruction in Bass brushing without stress on interdental cleaning, scaling and root planing, in combination with subgingival pulsated jet irrigation with dilute solutions of chlorhexidine, metronidazole or placebos. Twenty-five patients, 14 women and 11 men, each with periodontal pockets ≥ 4 mm, participated in a randomized, double-blind, placebo-controlled study. The patients were assigned to 4 groups: 2 test groups (0.02% chlorhexidine and 0.05% metronidazole) and 2 placebo groups (0.01% quinine sulphate and 0.09% sodium chloride). Subgingival plaque samples were obtained from at least 4 sites in each subject on days 0 (prior to scaling and root planing), 7, 28, 56 and 84. Subgingival irrigation was terminated on d 28. Darkfield microscopy was used to assess the effects of treatment on the subgingival microflora by observing 4 morphologic groups: cocci, motile organisms, spirochetes and others (i.e. non-motile rods and filaments). All the groups showed marked beneficial changes at the end of the 28-d irrigation period, with increases in cocci and decreases in motile forms and spirochetes to less than baseline values. These beneficial effects were maintained for at least 8 weeks after irrigation was stopped. Metronidazole was more effective in reducing motile forms, but the reduction was not significant at d 84. It was concluded that pulsating monojet subgingival irrigation as part of a simplified oral hygiene program, with or without an active antimicrobial agent at low concentration, is effective in reducing the motile and spirochete portions of the subgingival microflora. These effects might be enhanced and prolonged if suitable antimicrobial solutions of higher concentration were used.  相似文献   
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Five film-screen combinations were used to make five density-matched panoramic radiographs of a tissue-equivalent phantom skull using the Midwest/Morita Panoral x-ray machine. The radiographs were evaluated as to their diagnostic quality by twenty dental radiologists. The results demonstrate that proper screen-film selection can significantly reduce patient exposure without compromising diagnostic quality.  相似文献   
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Effects of temperature (25 and 37 degrees C), pH (4.9-10.5), and CaF2 on CaHPO4.2H2O (DCPD) hydrolysis were studied in a pH-stat. Octa-calcium phosphate (OCP) was the product at pH 6.2-6.8 and 25-37 degrees C; thermodynamically stable apatitic compounds were formed at higher pH and/or higher temperature. In the presence of CaF2, apatite was the product, its crystallinity improved, and the fluoride content increased as pH of the reaction decreased. The results demonstrate the remarkable ability of fluoride to promote the hydrolysis of an acidic calcium phosphate, DCPD, to apatite.  相似文献   
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Air turbine handpieces are manufactured with a wide range of alternative design features which may influence their suitability for particular clinical procedures. In this article a general account of these features is presented and their advantages and disadvantages are discussed. Some deficiencies in current methods of stating equipment specifications are reported and suggested improvements are given. Where appropriate, general recommendations are made regarding handpiece selection for clinical practice.  相似文献   
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