970 resultados para In-Drilling Alignment


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Objectives: Circumferential septal fiberotomy (CSF) following orthodontic treatment has been propagated to improve stability and prevent relapse of tooth alignment. The hypothesis of no difference between performed CSF and controls was tested. Methods: In 9 consecutively admitted patients at the end of orthodontic tooth alignment, the lower arch-wire was removed. CSF was performed from the mandibular canine to the central incisor on a randomly chosen side, while the contra-lateral side served as unsurgerized control. At baseline and every 4 weeks up to 6 months, study casts were taken and 1) analyzed using the Irregularity Index (II)according to Little and 2)photographed, traced and superimposed digitally. The translational and rotational movements of teeth as well as gingival parameters were analyzed as well. Results: By using the II and by superimposing the tracings, no statistically significant differences were found between the test (CSF) and control sides for any parameters. Moreover, CSF did not impinge on the gingival tissues. Conclusion: Since CSF did not improve stability of orthodontically aligned teeth nor prevent relapse during the healing pahse of up to 6 months, CSF should not be recommended following orthodontic therapy.

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OBJECTIVES: To evaluate whether or not preparation of the implant site with osteotomes instead of drilling may improve peri-implant bone density and/or osseointegration, and whether or not this further improves the predictability of immediate loading of SLA implants. MATERIAL AND METHODS: The second, third, and fourth premolars were extracted in both sides of the mandible in six dogs, and after at least 3 months four SLA implants were inserted into each side of the jaw. In three animals, the implant sites were prepared by means of osteotomes, while standard stepwise drilling was used in the remaining animals. In each side of the jaw, two non-adjacent implants were restored with single crowns 4 days after installation, while the remaining two implants were left without crowns to serve as non-loaded controls. After 2, 4, or 12 weeks of loading, specimens including the implants and surrounding tissues were obtained and processed for histologic analysis of undecalcified sections. RESULTS: All implants placed with osteotomes were lost (five before delivery of the crowns and the rest during the first week after loading). None of the conventionally inserted implants, however, was lost, and histomorphometrical analysis revealed similar soft- and hard peri-implant tissue characteristics at immediately loaded and non-loaded implants at all observation times. Average bone-to-implant contact was 59-72% at immediately loaded implants vs. 60-63% at non-loaded ones. CONCLUSION: Preparation of the implant site by means of osteotomes had a deleterious effect on osseointegration, while immediate loading of single, free-standing, SLA implants following a conventional surgical protocol did not jeopardize their osseointegration.

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This paper addresses the problem of estimating postoperative cup alignment from single standard X-ray radiograph with gonadal shielding. The widely used procedure of evaluation of cup orientation following total hip arthroplasty using single standard anteroposterior radiograph is known inaccurate, largely due to the wide variability in individual pelvic position relative to X-ray plate. 2D-3D image registration methods have been introduced to estimate the rigid transformation between a preoperative CT volume and postoperative radiograph(s) for an accurate estimation of the postoperative cup alignment relative to an anatomical reference extracted from the CT data. However, these methods require either multiple radiographs or a radiograph-specific calibration, both of which are not avaiable for most retrospective studies. Furthermore, these methods were only evaluated on X-ray radiograph(s) without gonadal shielding. In this paper, we propose to use a hybrid 2D-3D registration scheme combining an iterative landmark-to-ray registration with a 2D-3D intensity-based registration to estimate the rigid transfromation for a precise estimation of cup alignment. Quantitative and qualitative results evaluated on clinical and cadaveric datasets are given which indicate the validity of our approach.

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A cavovarus foot deformity was simulated in cadaver specimens by inserting metallic wedges of 15 degrees and 30 degrees dorsally into the first tarsometatarsal joint. Sensors in the ankle joint recorded static tibiotalar pressure distribution at physiological load. The peak pressure increased significantly from neutral alignment to the 30 degrees cavus deformity, and the centre of force migrated medially. The anterior migration of the centre of force was significant for both the 15 degrees (repeated measures analysis of variance (ANOVA), p = 0.021) and the 30 degrees (repeated measures ANOVA, p = 0.007) cavus deformity. Differences in ligament laxity did not influence the peak pressure. These findings support the hypothesis that the cavovarus foot deformity causes an increase in anteromedial ankle joint pressure leading to anteromedial arthrosis in the long term, even in the absence of lateral hindfoot instability.

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Osteoarthritis is thought to be caused by a combination of intrinsic vulnerabilities of the joint, such as anatomic shape and alignment, and environmental factors, such as body weight, injury, and overuse. It has been postulated that much of osteoarthritis is due to anatomic deformities. Advances in surgical techniques such as the periacetabular osteotomy, safe surgical dislocation of the hip, and hip arthroscopy have provided us with effective and safe tools to correct these anatomical problems. The limiting factor in treatment outcome in many mechanically compromised hips is the degree of cartilage damage which has occurred prior to treatment. In this regard, the role of imaging, utilizing plain radiographs in conjunction with magnetic resonance imaging, is becoming vitally important for the detection of these anatomic deformities and pre-radiographic arthritis. In this article, we will outline the plain radiographic features of hip deformities that can cause instability or impingement. Additionally, we will illustrate the use of MRI imaging to detect subtle anatomic abnormalities, as well as the use of biochemical imaging techniques such as dGEMRIC to guide clinical decision making.

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BACKGROUND: Percutaneous Kirschner wire fixation represents the classic treatment for displaced supracondylar humeral fractures in childhood. This type of treatment first requires satisfactory reduction of the fracture. Failure to achieve a satisfactory reduction or inadequate stabilization can result in instability of the fracture fragments, which can result in either an unsatisfactory cosmetic or functional outcome. In our experience, these problems can be overcome with the use of a small lateral external fixator. METHODS: Between 1999 and 2005, thirty-one of 170 Gartland type-III supracondylar humeral fractures were treated with a lateral external fixator. The outcome of treatment was analyzed with regard to limb alignment, elbow movement, cosmetic appearance, and patient satisfaction. RESULTS: In twenty-eight of the thirty-one patients, a satisfactory reduction was achieved with closed methods. All children except one had a normal or good range of movement. The cosmetic result was excellent in all cases. All of the children and their parents stated that they would choose this treatment again. CONCLUSIONS: The use of a small lateral external fixator seems to be a safe alternative for the treatment of displaced supracondylar fractures of the humerus when a closed reduction appears to be unattainable by means of manipulation alone or when sufficient stability is not achieved with standard methods of Kirschner wire fixation.

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The U.S. natural gas industry has changed because of the recent ability to produce natural gas from unconventional shale deposits. One of the largest and most important deposits is the Marcellus Shale. Hydraulic fracturing and horizontal drilling have allowed for the technical feasibility of production, but concerns exist regarding the economics of shale gas production. These concerns are related to limited production and economic data for shale gas wells, declines in the rates of production, falling natural gas prices, oversupply issues coupled with slow growth in U.S. natural gas demand, and rising production costs. An attempt to determine profitability was done through the economic analysis of an average shale gas well using data that is representative of natural gas production from 2009 to 2011 in the Marcellus Shale. Despite the adverse conditions facing the shale gas industry it is concluded from the results of this analysis that a shale gas well in the Marcellus Shale is profitable based on NPV, IRR and breakeven price calculations.

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After teaching regular education secondary mathematics for seven years, I accepted a position in an alternative education high school. Over the next four years, the State of Michigan adopted new graduation requirements phasing in a mandate for all students to complete Geometry and Algebra 2 courses. Since many of my students were already struggling in Algebra 1, getting them through Geometry and Algebra 2 seemed like a daunting task. To better instruct my students, I wanted to know how other teachers in similar situations were addressing the new High School Content Expectations (HSCEs) in upper level mathematics. This study examines how thoroughly alternative education teachers in Michigan are addressing the HSCEs in their courses, what approaches they have found most effective, and what issues are preventing teachers and schools from successfully implementing the HSCEs. Twenty-six alternative high school educators completed an online survey that included a variety of questions regarding school characteristics, curriculum alignment, implementation approaches and issues. Follow-up phone interviews were conducted with four of these participants. The survey responses were used to categorize schools as successful, unsuccessful, and neutral schools in terms of meeting the HSCEs. Responses from schools in each category were compared to identify common approaches and issues among them and to identify significant differences between school groups. Data analysis showed that successful schools taught more of the HSCEs through a variety of instructional approaches, with an emphasis on varying the ways students learned the material. Individualized instruction was frequently mentioned by successful schools and was strikingly absent from unsuccessful school responses. The main obstacle to successful implementation of the HSCEs identified in the study was gaps in student knowledge. This caused pace of instruction to also be a significant issue. School representatives were fairly united against the belief that the Algebra 2 graduation requirement was appropriate for all alternative education students. Possible implications of these findings are discussed.

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Manual drilling is a popular solution for programs seeking to increase drinking water supply in rural Madagascar. Lightweight, affordable and locally produced drilling equipment allows rapid implementation where access is problematic and funds are limited. This report will look at the practical implications of using manual drilling as a one-step solution to potable water in rural development. The main benefits of using these techniques are time and cost savings. The author uses his experience managing a drilling campaign in northeastern Madagascar to explore the benefits and limitations of one particular drilling methodology – BushProof’s Madrill technique. Just under 200 wells were drilled using this method in the course of one fiscal year (September 2011-September 2012). The paper explores what compromises must be considered in the quest for cost-effective boreholes and whether everybody - from the implementers to project managers to clients and lawmakers - are in agreement about the consequences of such compromises. The paper also discusses water quality issues encountered when drilling in shallow aquifers.

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Pat Williams emerged from the Mining City of Butte, Montana with a sense of grassroots, people-oriented politics. His inherent belief in the power of ordinary citizens carried him through the Montana Legislature and into Congress for a record-setting period. The accomplishments of his long career partially obscured his innate progressive and populist instinct that is reflective of the period of “in the Crucible of Change.” This film addresses Pat’s early years when his progressive instincts and activities resulted in pushback from the giant Anaconda Company which had held Montana hostage for 75 years. Pat is joined for part of the film by former campaign staffer, and now prominent media consultant, Michael Fenenbock for reflections on Pat’s 1978 “Door-to-Door to Congress” campaign, which demonstrated the power of his belief in the people on the other side of the doors. Pat Williams (b. 1937) rose from teaching grade school in his hometown of Butte, MT, to serving for the longest number of consecutive terms (9 terms, 18 years) in the US House of Representatives of anyone in Montana history. Pat was a member of the National Guard and attended UM in Missoula and William Jewel College, graduating from the University of Denver. Pat also served in the Montana legislature for 2 terms (1966 & 1968 elections). In 1969. Pat helped his legislative seat-mate John Melcher get elected as Montana’s Eastern District Congressman in the Special Election that June. Pat went to Washington DC as Melcher’s Executive Assistant. Upon returning to Montana, Pat headed up the Montana offices of the innovative Mountain Plains Family Education Program. In 1974, Pat ran unsuccessfully for Montana’s Western District Congressional seat in a three-way race with former Congressman Arnold Olsen and state Legislator Max Baucus. After the drafting and passage of the 1972 Montana Constitution, Pat was named a member of Montana’s first-ever Reapportionment Commission. In 1978 he successfully ran for Congress, conducting a massive grass-roots door-to-door campaign of 1½ years, reaching 50,000 doors. In a hotly contested 6-way Democratic primary, Pat won going away and also handily won the general election. Pat served in Congress from January, 1979 until January of 1997, 14 years representing the Western District and 4 years representing the entire state. Upon his retirement from Congress, in 1997 Williams returned to Montana where has been an instructor at the University of Montana and Senior Fellow and Regional Policy Associate at the Center for the Rocky Mountain West. He is a former member of the Montana Board of Regents and serves on a number of national education-related boards. In Congress Pat was a Deputy Whip of the U.S. House of Representatives and sat on committees on: Budget, Natural Resources, Education and Labor, and Agriculture. Pat’s leadership helped pass trailblazing legislation to assist hard-working middle-class families and ensure opportunities for every child. Pat’s fingerprints are on many pieces of important legislation, including the College Middle Income Assistance Act, the Family and Medical Leave Act, the Toddlers and Childhood Disability Act, the Library Services and Construction Act, and the Museum Services Act. Pat successfully sponsored the Lee Metcalf Wilderness Area and the Rattlesnake Wilderness area, helped save the Bob Marshall Wilderness from oil and gas exploration, and helped ban geothermal energy drilling near the borders of Yellowstone National Park. As Chairman of The Post-Secondary Education Committee, he protected the National Endowment for the Arts from elimination, a remarkable undertaking during a very trying time for the Agency. Pat worked tirelessly with Tribal College Leaders to build Montana’s seven Tribal Colleges. He was also responsible for the legislation that created The American Conservation Corps, which became the Corporation for National Service, giving thousands of America’s young people a chance to serve their country and pursue higher education. Pat lives in Missoula with his wife Carol Griffith Williams, former Montana Senate Majority Leader. They have three children and five grandchildren.

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The Williston basin has been producing oil and gas since the 1950s, but production has increased recently due to use of hydraulic fracturing and horizontal drilling technologies to extract oil and gas from the Bakken and Three Forks Formations. As concern about effects of energy production on surface-water and groundwater quality increases, the characterization of current water-quality conditions is highly important to the scientific community, resource managers, industry, and general public.

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Oil and gas have been found in the Triassic strata of Wyoming. Although the Triassic has not as yet proven to be a large producing horizon it is very probable that ad­ditional oil will be found in Triassic strata in the future, and it is one of the goals at which oil well drillers aim their tools.