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11.
Abstract: Aim: To compare plaque removal efficacy of Oral‐B CrossAction (CA) used for 1 min with an American Dental Association (ADA) manual toothbrush used for 2 or 5 min in an examiner‐blind, three‐treatment, six‐period crossover study. Materials and methods: After refraining from all oral hygiene procedures for 23–25 h, subjects were randomly assigned to one of nine possible six‐period (visit) treatment sequences. Plaque was assessed at baseline (Rustogi Modified Navy Plaque Index). Post‐brushing scores were recorded after brushing with a marketed dentifrice and the assigned toothbrush for the specified duration. The same procedure was followed at each of six subsequent visits. Clinical measurements were carried out by the same examiner. Results: Forty subjects completed the study. All three treatments effectively removed plaque from the whole mouth, along the gingival margin and from approximal surfaces. Whole mouth and gingival margin plaque removal scores with CA for 1 min did not differ significantly from scores with the ADA toothbrush used for 2 min. The ADA brush used for 5 min showed significantly greater whole mouth (P < 0.001) and gingival margin (P < 0.001) plaque reduction than the two other treatments. Approximal plaque removal scores did not differ between the three treatments. Conclusions: Efficient plaque removal can be achieved after 1 min of brushing with CA. The amount of plaque removed did not differ significantly from that achieved with the ADA brush after 2 min of brushing. Greater whole mouth and gingival margin plaque removal scores were seen with the ADA brush after 5 min.  相似文献   
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OBJECTIVE: To evaluate the safety and plaque removal efficacy of an advanced rotating-oscillating power toothbrush relative to a sonic toothbrush with either a standard or compact brush head. METHODOLOGY: Two studies used a randomized, examiner-blind, two-treatment, crossover design. In Study 1, subjects were instructed to use their first randomly assigned toothbrush for five to seven days and then, after abstaining from all oral hygiene for 24 hours, were assessed with the Rustogi, et al. Modified Navy Plaque Index. They then brushed for two minutes and post-brushing plaque scores were recorded. Subjects were assigned to the alternate toothbrush and the procedures were repeated. In Study 2, subjects alternated using both brushes for approximately 10 days, then had four study visits three to four days apart (some variability based on patient scheduling). In Study 1, Oral-B Triumph with a FlossAction brush head and Sonicare Elite 7300 with a full-size, standard head were compared in a two-treatment, two-period crossover study. Study 2 compared Oral-B Triumph with a FlossAction brush head and Sonicare Elite 7300 with a compact head in a two-treatment, four-period crossover study. RESULTS: Fifty subjects completed Study 1 and 48 completed Study 2. All brushes were found to be safe and significantly reduced plaque after a single brushing. In Study 1, Oral-B Triumph was statistically significantly (p < 0.001) more effective in plaque removal than Sonicare Elite 7300 with the full-size brush head: whole mouth = 24% better, marginal = 31% better, approximal = 21% better. In Study 2, Oral-B Triumph was statistically significantly (p < 0.001) more effective than Sonicare Elite 7300 with the compact brush head: whole mouth = 12.2% better, marginal = 14.6% better, approximal = 12% better. CONCLUSION: Oral-B Triumph with its rotation-oscillation action was significantly more effective in single-use plaque removal than Sonicare Elite 7300 with its side-to-side sonic action when fitted with either a standard or a compact brush head.  相似文献   
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Background: The facial region has traditionally been quantified using linear anthropometrics. These are well established in dentistry, but require expertise to be used effectively. The aim of this study was to augment the utility of linear anthropometrics by applying them in conjunction with modern 3‐D morphometrics. Methods: Facial images of 75 males and 94 females aged 18–25 years with self‐reported Caucasian ancestry were used. An anthropometric mask was applied to establish corresponding quasi‐landmarks on the images in the dataset. A statistical face‐space, encoding shape covariation, was established. The facial median plane was extracted facilitating both manual and automated indication of commonly used midline landmarks. From both indications, facial convexity angles were calculated and compared. The angles were related to the face‐space using a regression based pathway enabling the visualization of facial form associated with convexity variation. Results: Good agreement between the manual and automated angles was found (Pearson correlation: 0.9478–0.9474, Dahlberg root mean squared error: 1.15°–1.24°). The population mean angle was 166.59°–166.29° (SD 5.09°–5.2°) for males–females. The angle‐pathway provided valuable feedback. Conclusions: Linear facial anthropometrics can be extended when used in combination with a face‐space derived from 3‐D scans and the exploration of property pathways inferred in a statistically verifiable way.  相似文献   
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Background: Azithromycin is a macrolide antibiotic that is active against several periodontal pathogens. Macrolides are taken up and concentrated inside gingival fibroblasts, which could influence their pharmacokinetics. This study tests the hypothesis that steady‐state levels of azithromycin are higher and more sustained in gingival crevicular fluid (GCF) than in serum. Methods: Four healthy patients received an initial dose of 500‐mg azithromycin followed by 250‐mg doses on each of the next 2 days. Serum and GCF samples were obtained 2 hours after the last dose on day 2, and on days 4 and 7. GCF samples were collected from maxillary posterior sites with paper strips. The strips were pooled and eluted with high‐purity water. After extraction, the azithromycin content of the serum samples and GCF eluates was determined with an agar diffusion bioassay. Results: On days 2, 4, and 7, the concentrations of azithromycin in blood serum were 0.22 ± 0.02, 0.08 ± 0.02, and 0.04 ± 0.01 μg/mL, respectively. The concentrations in GCF were 8.82 ± 1.25, 7.90 ± 1.72, and 7.38 ± 1.15 μg/mL, respectively. Mean GCF levels were significantly higher than mean serum levels (P ≤0.02; paired t test). Conclusions: The findings demonstrate that the pharmacokinetic profiles of azithromycin are different in GCF and serum. At steady state, azithromycin concentrations in GCF were higher and more sustained than those in serum. Based on previous studies, the levels observed in GCF were above the minimal inhibitory concentration for Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, and Prevotella intermedia.  相似文献   
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BACKGROUND: Polymorphonuclear leukocytes (PMNs) are exposed to high concentrations of polyamines in the inflamed periodontium and possess a transport system for taking up these compounds. Previous studies suggest that polyamines are involved in priming of the PMN respiratory burst by tumor necrosis factor-alpha (TNF-alpha) and can stabilize DNA against degradation. The purpose of this study was to determine whether exogenous polyamines can modulate priming by TNF-alpha or delay nuclear changes associated with PMN apoptosis (programmed cell death). METHODS: Isolated human PMNs were incubated with putrescine or spermidine in vitro. Superoxide generation was measured with a cytochrome C reduction assay, and apoptotic changes were assessed by fluorescence microscopy (after cell staining with acridine orange and ethidium bromide). RESULTS: Incubation with 1 mM putrescine for 1 hour inhibited superoxide production by TNF-primed PMNs by 20%, but enhanced the production of superoxide by unprimed cells by 38%. Both effects were dose dependent and statistically significant (P <0.03, repeated measures ANOVA and Dunnett's test). Spermidine had no significant effects on PMN oxidative function. With regard to apoptosis, 1 mM putrescine or spermidine produced a statistically significant reduction in the proportion of apoptotic PMNs within 6 to 9 hours (P <0.05). In cells incubated for 7 hours with 300 microM putrescine or spermidine, the proportion of apoptotic cells was approximately 30% lower than in untreated controls (P <0.05, Dunnett's test). The delay of apoptosis by spermidine was less profound than that produced by TNF-alpha and was not additive to the effects of this cytokine. CONCLUSIONS: Polyamines could potentially impair the priming of PMN oxidative function by TNF-alpha at sites where this cytokine is present. In the absence of TNF-alpha, polyamines could enhance PMN superoxide release and enhance the maintenance of PMN function in the periodontal pocket.  相似文献   
16.
Living organ donors face direct costs when donating an organ, including transportation, lodging, meals, and lost wages. For those most in need, the National Living Donor Assistance Center (NLDAC) provides reimbursement to defray travel and subsistence costs associated with living donor evaluation, surgery, and follow‐up. While this program currently supports 9% of all US living donors, there is tremendous variability in its utilization across US transplant centers, which may limit patient access to living donor transplantation. Based on feedback from the transplant community, NLDAC convened a Best Practices Workshop on August 2, 2018, in Arlington, VA, to identify strategies to optimize transplant program utilization of this valuable resource. Attendees included team members from transplant centers that are high NLDAC users; the NLDAC program team; and Advisory Group members. After a robust review of NLDAC data and engagement in group discussions, the workgroup identified concrete best practices for administrative and transplant center leadership involvement; for individuals filing NLDAC applications at transplant centers; and to improve patient education about potential financial barriers to living organ donation. Multiple opportunities were identified for intervention to increase transplant programs’ NLDAC utilization and reduce financial burdens inhibiting expansion of living donor transplantation in the United States.  相似文献   
17.
Nurses often experience positive and negative dimensions of caring for dying clients and their families. This project aimed to compare stress experienced by urban and rural community nurses working with palliative-care clients in the home. Participants included five nurses working in rural Australia and seven nurses working in an urban area. Transcribed data from unstructured audio-taped interviews were coded for common and contrasting themes, and a comparison was made of the stress experienced by the two groups of nurses. The major themes were role conflict and definition, family dynamics, time and workload. For both groups of nurses, the impact of family relationships and role conflict within the community impacted significantly to the stress they experienced. Debriefing opportunities for nurses to discuss stress, including educational and support sessions, is an essential component of best practice. Rural nurses had the additional stress of trying to provide a 24 h service over vast distances with a lack of financial resources.  相似文献   
18.
Trichinella infection and clinical disease   总被引:1,自引:0,他引:1  
Trichinellosis is caused by ingestion of insufficiently cooked meat contaminated with infective larvae of <it>Trichinella</it> species. The clinical course is highly variable, ranging from no apparent infection to severe and even fatal disease. We report two illustrative cases of trichinellosis. Returning to Denmark a few days after having eaten roasted pork in the Republic of Serbia, a female patient suffered from severe vomiting, epigastric pain, diarrhoea, and later myalgia, generalized oedema, and prostration. A biopsy showed heavy infestation with <it>Trichinella spiralis</it>, 2000 larvae/g of muscle. Life-threatening cardiopulmonary, renal and central nervous system complications developed. The patient recovered after several months. Her husband, who also ate the pork, did not have clinical symptoms, but an increased eosinophil count and a single larva in a muscle biopsy confirmed infection. The epidemiology, clinical manifestations, diagnosis, treatment and prevention of trichinellosis are reviewed.   相似文献   
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