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This study investigated the hypothesis that coating eroded teeth with a resin-based dentin bonding agent gave protection from tooth wear. Nineteen adults with palatal tooth wear exposing dentin were recruited, following referral by their general dental practitioner. Alternate teeth were coated with the resin adhesive, while the uncoated teeth acted as controls. Accurate impressions of the eroded teeth, onto which were cemented machined stainless steel discs to act as reference areas, were scanned with a non-contacting laser profilometer at 3, 6, 12 and 24 months. The mean thickness of resin at baseline application was 0.15 mm and, from 0 to 6 months, the rate of wear of the control teeth was higher than those covered with Seal & Protect. There was a statistically significant difference in "wear" measured between resin covered and control teeth at three months. The Inter Class Correlations (repeated measurements) for the step heights obtained for the original and repeat impressions was excellent at 0.99. This study shows that coating eroded teeth with a resin-based adhesive has the potential to prevent further tooth wear.  相似文献   
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BackgroundDeep venous thrombosis (DVT) occurs in 0.1% of persons per year, affecting 15%–40% of general surgical procedures without prophylaxis. Thromboembolic prophylaxis is not commonly used after orthotopic liver transplantation (LT) owing to the risks of bleeding and coagulopathy. Cirrhosis and the association with the coagulation cascade, before and after transplantation, are not well understood. The purpose of this study was to determine the incidence of DVT and its risk factors after LT.MethodsWe retrospectively reviewed LTs performed at our center from 2005 to 2012. We identified patients with Doppler examinations showing DVT after LT, platelet count, and international normalized ratio (INR) at time of DVT, associated symptoms, DVT prophylaxis, and perioperative risk factors. We determined the incidence of DVT, the odds ratio of each preoperative risk factor, the difference in platelet count and INR between those with and without a DVT, and the weighted risk of each factor in the development of DVT with the use of logistic regression modeling.ResultsOf 314 patients, the incidence of DVT was 8.6% (27/314). Between those with and without DVT there was no significant difference in age, sex, platelet count, INR, infection, hepatocellular cancer, use of venous bypass, and prior surgery. There was a significant difference in mobility, 67% vs 20% (P < .0001), and the use of factor VII, 11% vs 2% (P < .05). The estimated risk for of developing DVT for patients with neither of these factors was 4%; with factor VII the risk rose to 17%; with mobility difficulty the risk rose to 23%; and with both the risk was 62%. In our entire population, there were no cases of pulmonary embolism.ConclusionsThe risk of developing a DVT after LT is ≥9% even with mechanical DVT prophylaxis. Consideration should be given to using both mechanical and chemical prophylaxis after LT.  相似文献   
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While ophthalmology as a surgical branch itself has evolved technologically with newer instruments, techniques and procedures; ophthalmic surgical training appears to have stagnated in terms of how it is delivered and how trainees’ learning and performance are assessed. This collaborative editorial attempts to identify the lacunae in ophthalmic residency training and highlight how technological tools such as surgical simulators can be incorporated into ophthalmic training even in limited-resource settings with good results.  相似文献   
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Purpose:To compare different endophthalmitis prophylaxis methods adopted in cataract surgery (manual small-incision cataract surgery and phacoemulsification) between the years 2013 and 2021 in the community eye care section of a tertiary eye care hospital in South India and report their outcomes.Methods:All cataract surgeries performed from January 2013 to December 2021 (2,46,874 surgeries) at a single center were included in this retrospective study. The different endophthalmitis rates with each regimen were analyzed and evaluated.Results:70,081 surgeries were performed from January 2013 to February 2015, where Tobramycin was added to Balanced Salt Solution (BSS) (Group A). From March 2015 to January 2017, 63,245 surgeries were performed when intracameral Moxifloxacin was given (Group B). From February 2017 to December 2021, 1,13,548 surgeries were performed were Amikacin was added to BSS (Group C). In total, 42 cases of postoperative endophthalmitis were reported during the study period (0.02%). There was no significant difference in the endophthalmitis rates between groups A and B (P = 0.4152); however, there was a significant decrease in endophthalmitis rates in group C when compared with group A (P = 0.04) and group B (P = 0.006).Conclusion:There was a significant reduction in the rates of endophthalmitis following the addition of amikacin in irrigating BSS. Nocardia was one of the predominant organisms isolated from these endophthalmitis patients. This is the first single-center study to report a comparative analysis of different endophthalmitis prophylactic measures in a community eye care set up with a high incidence of Nocardia endophthalmitis prevented with amikacin in BSS irrigating solution.  相似文献   
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The increase in the population creates an increased demand for construction activities with eco-friendly, sustainable, and high-performance materials. Insulated concrete form (ICF) is an emerging technology that satisfies the sustainability demands of the construction sector. ICF is a composite material (a combination of expanded polystyrene (EPS) and geopolymer concrete (GPC)) that enhances the performance of concrete (such as thermal insulation and mechanical properties). To investigate the axial strength performance, five different types of prototypes were created and tested. Type I (without reinforcement): (a) hollow EPS without concrete, (b) alternative cells of EPS filled with concrete, (c) and all the cells of EPS filled with concrete; and Type II (with reinforcement): (d) alternative cells of EPS filled with concrete; (e) and all the cells of EPS filled with concrete. Amongst all the five prototypes, two grades of GPC were employed. M15 and M20 grades are used to examine the effectiveness in terms of cost. For comparing the test results, a reference masonry unit was constructed with conventional clay bricks. The main aim of the investigation is to examine the physical and mechanical performance of sandwich-type ICFs. The presence of polystyrene in ICF changes the failure pattern from brittle to ductile. The result from the study reveals that the Type II prototype, i.e., the specimen with all the cells of EPS filled with concrete and reinforcement, possesses a maximum load-carrying capacity greater than the reference masonry unit. Therefore, the proposed ICF is recommended to replace the conventional load-bearing system and non-load-bearing walls.  相似文献   
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