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81.
Sanguinaria extract, which contains benzophenanthridine alkaloids, has been used as a folk medicine for many years. Minimum inhibitory and minimum bactericidal concentrations (MIC and MBC values) for sanguinarine were determined for common and etiologically important plaque bacteria. Because the efficacy of sanguinarine is believed to be enhanced by zinc, isobolograms were assessed to determine their mode(s) of interaction. Hydrogen ion concentration influenced the inhibitory activity of both sanguinarine and zinc. For sanguinarine, at the optimum pH (6.5), MIC values were 4 or 8 micrograms/ml for Streptococcus mutans, Streptococcus sobrinus, Streptococcus sanguis, Actinomyces viscosus and Actinomyces naeslundii. MIC values were 0.125-0.50 mmol Zn/ml. MBC values ranged from 1 to 8 mmol Zn/ml at pH 5.5. Isobologram data revealed that sanguinarine and zinc interacted synergistically. Viadent oral rinse, which contained 300 micrograms sanguinaria extract/ml and 0.2% zinc chloride (14.9 mmol Zn/l), was inhibitory to all strains tested. MIC values were 1 or 2% (ml Viadent oral rinse/100 ml aqueous solution) for all strains except A. viscosus for which the MIC value was 12% (vol/vol).  相似文献   
82.
83.
Moral reasoning in dental hygiene students   总被引:1,自引:0,他引:1  
Sixty-five students participated in a study designed to identify the level of moral reasoning of dental hygiene students. Comparisons were made with typical college students and a normative group composed of individuals representing a cross-section of ages and educational levels. The relationships among level of moral reasoning and clinical performance, other selected academic measures, and cognitive style were also assessed. The results indicated that post-certificate dental hygiene students reasoned about moral dilemmas at a higher level than the normative group and at the same level as the college student group. In addition, clinical performance, National Board Dental Hygiene Examination scores, Dental Hygiene Aptitude Test (reading scores), high school rank, and cognitive style correlated positively with level of moral reasoning and specific stages of moral development for postcertificate students.  相似文献   
84.
85.
A 17-year-old white boy with signs, symptoms, and family history of angiokeratoma corporis diffusum universale, Anderson-Fabry disease (AFD), developed recurrent and then persistent swelling of both lips, erythematous hyperplastic gingivae, and a pebbled tongue. Positive blood findings were raised serum IgE, decreased T-cell level, and increased B-cell level. Histopathology of the gingiva showed noncaseating granulomas with multinucleate giant cells containing Schaumann bodies and large plasma-cell infiltrates in which immunofluorescence demonstrated immune globulins of several classes. Electron microscopy and histochemistry demonstrated ceramide in the vasculature. No glycolipid was found in the macrophages or giant cells of the granulomas which, in contrast, resembled sarcoid reactions. Plasma cells with Russell bodies and immune reaction-induced degranulation of mast cells were also identified. The pathogenesis of the oral findings possibly relates to altered immune reactivity associated with damage to the microvasculature analogous to that in Melkersson-Rosenthal syndrome.  相似文献   
86.
87.
Zinc ions, chlorhexidine (CHX) and cetylpyridinium chloride (CPC) are all known to inhibit production of volatile sulfur compounds (VSCs). The objective was to examine the anti-VSC dose-response effects of each of the above agents. Oral malodor was induced in 13 test subjects using the cysteine challenge method. The oral VSC response to rinses with 6 mm l-cysteine (pH 7.2) before and 1, 2 and 3 h after rinsing with zinc ions (Zn2+: 0.1, 0.3 and 1.0%), CHX and CPC (0.025 and 0.2%) was measured. Mouth air was analysed for VSC by gas chromatography (GC) according to current methodology. Zinc had a marked dose- and time-dependent anti-VSC effect. Zinc at 1% concentration had a somewhat unpleasant taste, whereas the lowest concentration was found acceptable. Chlorhexidine maintained a moderate anti-VSC effect over time. At 3 h, 0.2% CHX was the most effective agent but tasted relatively unpleasant. Cetylpyridinium at a concentration of 0.2% was only marginally more effective than 0.025% CHX over the 3 h, while 0.025% CPC had no better anti-VSC effect than water at both 2 h and 3 h. It was concluded that the three test agents demonstrated different anti-VSC kinetics. Although Zn had the best anti-VSC effect at 1 h, 0.2% CHX was at least as effective as 1% Zn at 3 h, most likely as a result of its unique substantivity.  相似文献   
88.
89.
Osteopathy has grown rapidly. Given their common action on children and adolescents, the collaboration between dentofacial orthopedics and osteopathy is increasingly common. It therefore becomes necessary and urgent to investigate whether, based on data acquired from science, there is evidence of possible interrelations between the two disciplines. After reviewing the literature, very few scientific publications demonstrate the utility of osteopathy and its relationships with other disciplines. However, the relationship between occlusion and posture seem relatively proven, especially in the sagittal direction. On the other hand, although the mobility of the cranial bones is established, the primary respiratory motion is still subject to controversy, even among osteopaths. This, even as orthodontics has long been accused of countering the primary respiratory motion of cranial bones (PRM). Today osteopaths do not reject orthodontics anymore, because the return to a physiological bite situation is considered beneficial. According to expert opinion (without proof, however), some orthodontic devices (like headgears) which block the sutures are still to be avoided and require appropriate monitoring osteopathy. The controversy over the adverse effects of orthodontic treatment is becoming more nuanced by osteopaths, and modern orthodontics claiming a ?global? approach of patient, collaboration may be possible in future year.  相似文献   
90.
The role of the dental team in caries management by risk assessment is critical to successful patient outcomes. Positive patient interactions and communication, proper appointment scheduling, diagnostics and data gathering, as well as implementation of noninvasive or minimally invasive procedures can be the responsibility of all members of the dental team. This article will evaluate the role of the clinical and administrative staff in maintaining a practice with a focus on disease prevention and management..  相似文献   
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