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Objectives: The aim of this study was to examine systematically the data published on the efficacy of mandibular implant-retained overdentures from the patient's perspective.
Material and methods: Medline, Embase, The Cochrane Central Register of Controlled Trials and The Cochrane Systematic Reviews Database were searched and complemented by hand searching. All randomized-controlled trials published in English or French up to April 2007 were included, in which conventional dentures and mandibular implant overdentures in adult edentulous individuals were compared. The outcomes of interest were patient satisfaction, oral and general health-related quality of life. Random effects models were used to pool the effect sizes (ES) of all included studies.
Results: Ten publications of seven randomized-controlled trials were identified and eight were included in the meta-analysis. When compared with mandibular conventional dentures, implant overdentures were rated to be more satisfactory at a clinically relevant level [pooled ES 0.80, z =3.56, 95% confidence intervals (CI) 0.36–1.24, P =0.0004], but a statistical heterogeneity was found (χ2=31.63, df=5, P <0.00001, I 2=84%). The pooled ES for oral health quality of life was −0.41 ( z =1.31, 95% CI, −1.02 to 0.20; P =0.19, χ2=11.53, df=2, P <0.003, I 2=83%). There was a lack of evidence to show the impact of mandibular implant overdenture on perceived general health.
Conclusions: Our findings suggest that, although mandibular implant-retained overdentures may be more satisfying for edentulous patients than new conventional dentures, the magnitude of the effect is still uncertain. There is a need for additional evidence including cost-effectiveness analyses on the impact of mandibular implant overdentures and conventional dentures.  相似文献   
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Naevus comedonicus of the scalp   总被引:1,自引:0,他引:1  
We report the case of a 3-year-old boy with naevus comedonicus, characterized by confluent clusters of dilated follicular orifices plugged with keratinous material that resemble open comedones, located on the scalp.  相似文献   
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Objective measurements derived from digitized laryngeal stroboscopic images were used to demonstrate changes in vocal fold vibration and in the size of benign lesions after 3 months of voice therapy. Forty chronically dysphonic patients were studied. By means of a rigid stroboscope, pretreatment and posttreatment recordings were made of the vocal folds at rest and under stroboscopic light during phonation. From each recording, images of the positions at rest and during vibration at maximal opening and at maximal closure were digitized. The surface areas of any lesions and of the glottal gap were independently measured in the digitized images by 2 experienced laryngologists. Referential distances were determined in order to compensate for discrepancies in magnification in the various recordings. After 3 months of voice therapy, significant improvement in lesion size and degree of maximal closure during vibration could be demonstrated in about 50% of the patients. The degree of maximal opening did not prove to be a significant parameter.  相似文献   
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BACKGROUND: Earlier studies have reported that endovascular abdominal aortic aneurysm (EAAA) repair yields lower total profit margins than open AAA (OAAA) repair. This study compared EAAA versus OAAA based on contribution margin per day, which may better measure profitability of new clinical technologies. Contribution margin equals revenue less variable direct costs (VDCs). VDCs capture incremental resources tied directly to individual patients' activity (eg, invoice price of endograft device, nursing labor). Overhead costs factor into total margin, but not contribution margin. METHODS: The University of Michigan Health System's cost accounting system was used to extract fiscal year 2002-2003 information on revenue, total margin, contribution margin, and duration of stay for Medicare patients with principal diagnosis of AAA (ICD-9 code 441.4). RESULTS: OAAA had revenues of $37,137 per case versus $28,960 for EAAA, similar VDCs per case, and thus higher contribution margin per case ($24,404 for OAAA vs $13,911 for EAAA, P < .001). However, OAAA had significantly longer mean duration of stay per case (10.2 days vs 2.2 days, P < .001). Therefore, mean contribution margin per day was $2948 for OAAA, but $8569 for EAAA ( P < .001). CONCLUSIONS: On the basis of contribution margin per day, EAAA repair dominates OAAA repair. The shorter duration of stay with EAAA allows higher throughput, fuller overhead amortization, better use of scarce inpatient beds, and higher health system profits. Surgeons must understand overhead allocation to devices, especially when new technologies cut duration of stay markedly.  相似文献   
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Most health-care costs are fixed and sunk. Fixed costs do not vary with the level of patient activity, and once sunk they cannot be easily reversed. We must rethink how we manage the expensive investments in our health care infrastructure, which is where most costs lie. The conventional approaches to rationing care have failed. Physicians have been told to lower the cost of care by rationing resources. This rationing includes reducing the length of patients' hospital stays but this does not work as intended. A new paradigm advocates making more and better use of existing assets and by pursuing improvements incrementally and at the bedside. Elements include flexing intensive care unit beds, improving operating room efficiencies, and rationalizing health care capacity.  相似文献   
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