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Objective: To investigate the color alterations in enamel following the use of different orthodontic bonding resins and adhesive residue–removal burs.Materials and Methods:Metal brackets were bonded to extracted human premolars (n  =  175) by using an etch-and-rinse adhesive system, a self-etch adhesive system (SEP), or a resin-modified glass ionomer cement (RMGIC). After 24 hours of photoaging, the brackets were removed and the adhesive residue on the tooth surfaces was cleaned with either a tungsten carbide bur or a Stainbuster bur. Tooth colors were measured with a spectrophotometer at baseline, after adhesive removal, and after additional photoaging. Color evaluation was made, and color differences induced by photoaging were calculated. Statistical evaluation was made using the Kruskal-Wallis test and the Mann-Whitney U-test, with Bonferroni correction.Results:All specimens showed discoloration at varying levels. The highest color change was observed in the etch-and-rinse adhesive/tungsten carbide bur group. When the etch-and-rinse and self-etch adhesives were used, adhesive-remnant removal with Stainbuster burs resulted in significantly lower discoloration. The type of bur did not affect the extent of enamel discoloration in the RMGIC group.Conclusions:Orthodontic treatment alters the original color of enamel, and both the adhesive system and the resin-removal methods are responsible for this change. When brackets are bonded with the etch-and-rinse system or the SEP, cleaning the adhesive residuals with Stainbuster burs is recommended for minimal change. RMGIC can be safely cleaned with tungsten carbide burs.  相似文献   
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AIM: Recent findings show that the vaginal mucosa can develop an allergic response to environmental allergens and there is a strong association between atopy and some recurrent vulvovaginal infections. In this study, we investigated prospectively the rate of atopy in patients with recurrent vulvovaginitis of undetermined etiology (RVV). MATERIAL AND METHODS: After being investigated by a gynecologist, 35 patients with RVV who were considered as undetermined etiology formed the study group. The control group consisted of 150 healthy females. Study and control groups were investigated for atopy by means of skin prick test for common aeroallergens. Associated allergic disease and familial atopy history of the subjects were recorded. RESULTS: The rate of atopy (11/35; 31.4% vs 9/150; 6%) was significantly higher (P < 0.001) in the study group than in the controls. Familial history of atopy was significantly more frequent in the study group than in the controls (10/35; 28.6% vs 8/150; 5.3%, P < 0.05). RVV in atopics is more associated with seasonal rhinitis than in nonatopics (5/11; 45.4% vs 2/24; 8.3%, P < 0.05). CONCLUSION: We concluded that a significant number of RVV is associated with atopy. Although the exact mechanism(s) of this relationship remains to be investigated atopy might be a causative and/or contributing factor in the pathogenesis of RVV.  相似文献   
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The purpose of the study was to evaluate the effectiveness of caspofungin and voriconazole in the treatment of experimental Aspergillus otits media in an experimental rabbit model. A total of 30 New Zealand white rabbits were divided into four treatment groups and one control group. The rabbits were immunosuppressed by cyclophosphamide and triamcinolone acetonide. The right ear of each rabbit was infected by an injection of the inoculum of 0.1 ml (8.6 × 103 CFU/0.1 ml) of Aspergillus fumigatus into the middle ear cavity. At 72 h after the inoculation, amphotericin B 1 mg/kg per day (n = 6), itraconazole 10 mg/kg per day (n = 6), voriconazole 10 mg/kg per day (n = 6) and caspofungin 5 mg/kg per day (n = 6) were injected to each treatment group. No antifungal drug was administered to the control group (n = 6). Clinical and histopathological examination scores and microbiological analysis of middle ear mucosa were compared.There was statistically significant difference in the clinical scores, histopathological scores, and mean CFU/g between the treatment and control groups (P < 0.05). There was no statistically significant difference among the treatment groups in the clinical and histopathological scores, whereas there was statistically significant difference in the mean CFU/g (P < 0.05). The mean CFU/g of amphotericin B and caspofungin groups were similar and both were lower than the itraconazole and voriconazole groups. Also, the mean CFU/g of voriconazole group was lower than the itraconazole group (P < 0.05). Caspofungin and voriconazole were demonstrated at least as effective as amphotericin B and itraconazole. We suggest that caspofungin and voriconazole may be considered for the treatment of fungal infection of the ear.  相似文献   
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Bilateral anterior ischemic optic neuropathy is a rare complication of massive haemorrhage and related hypotension and anaemia in young individuals. We report a 34-year-old woman with bilateral non-arteritic ischemic optic neuropathy (NAION) after a massive spontaneous abortion-related haemorrhage who presented with sudden painless visual loss in her left eye. Visual acuity was 20/20 in the right eye with only hand motion discernible in the left eye. There was a left relative afferent papillary defect (RAPD). Fundus examination revealed bilateral swollen, hyperaemic optic discs and nerve fiber layer haemorrhages. Brain MRI and magnetic resonance venography were normal. The diagnosis of bilateral NAION was made and intravenous pulse corticosteroid therapy (1000 mg/day) was administered for three days. On the sixth day, optic disc oedema regressed bilaterally and on the third week, the visual acuity improved to 20/80 in the left eye. The visual field showed only a small spared area in the nasal region, and persistent RAPD was present. After two months, fundus examination showed a small and crowded optic disc on the right and a pale optic disc on the left. Severe acute haemorrhage is an important risk factor for NAION in healthy young individuals. In addition to correction of hypotension and anaemia, intravenous high dose corticosteroid might be beneficial for treatment.  相似文献   
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Background  

There are limited data about the epidemiology and risk factors/indicators of gingivitis, aggressive periodontitis (AgP) and chronic periodontitis (CP) in Jordan. The aim of this study was to assess the prevalence and risk indicators of gingivitis, AgP and CP.  相似文献   
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The postoperative development of necrotizing enterocolitis (NEC) following major surgery in neonates has often been described. We report herein the case of an older infant in whom postoperative NEC developed following emergency repair of an incarcerated inguinal hernia. Received: March 8, 2000 / Accepted: November 20, 2000  相似文献   
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