21 resultados para Arms Race
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In this study, curved maxillary molar root canals were instrumented with RaCe rotary system to evaluate: 1. the occurrence of canal transportation using a radiographic platform; 2. the action of the instruments on the dentin walls, centering ability and canal enlargement by analysis of digital images; and the percentage of regular dentin surfaces and debris within the canal by histological analysis. Ten mesiobuccal roots of extracted human maxillary molars were embedded in acrylic resin and sectioned at the middle and apical thirds. Root canal shaping was performed using the RaCe rotary system at 250 rpm and 1 Ncm torque. Each instrument set was used five times according to a crowndown technique in the following sequence: 40/0.10, 35/0.08, 25/0.06, 25/0.04, 25/0.02 (working length - WL), 30/0.02 (WL) and 35/0.02 (WL). Each instrument was inserted until resistance was felt and then pulled back, followed by brushing movements towards all canal walls. Each specimen was assessed by three study methods: radiographic platform, digitized image assessment and histological analysis. The radiographic platform showed lack of apical transportation. No statistically significant difference (Wilcoxon test, p>0.05) was found between the middle and apical thirds regarding instrument action on dentin walls, centering ability, area of root canal enlargement, percentage of regular dentin surfaces and debris within the root canal. It may be concluded that RaCe system is a suitable method for the preparation of curved root canals, regarding the maintenance of root canal original path, action on dentin walls, canal enlargement and removal of debris from the root canal lumen.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Objective. To evaluate the potential effects of race on clinical characteristics, extent of disease, and response to chemotherapy in women with postmolar low-risk gestational trophoblastic neoplasia (GTN).Methods. This non-concurrent cohort study was undertaken including patients with FIGO-defined postmolar low-risk GTN treated with comparable doses and schedules of chemotherapy at the New England Trophoblastic Disease Center (NETDC) between 1973 and 2012. Racial groups investigated included whites, African American and Asians. Information on patient characteristics and response to chemotherapy (need for second line chemotherapy, reason for changing to an alternative chemotherapy, number of cycles/regimens, need for combination chemotherapy, and time to hCG remission) was obtained.Results. Of 316 women, 274 (86.7%) were white, 19 (6%) African American, and 23 (7.3%) Asian. African Americans were significantly younger than white and Asian women (p = 0.008). Disease presentation, and extent of disease, including antecedent molar histology, median time to persistence, median hCG level at persistence, rate of D&C at persistence, presence of metastatic disease, and FIGO stage and risk score were similar among races. Need for second line chemotherapy (p = 0.023), and median number of regimens (p = 0.035) were greater in Asian women than in other races.Conclusions. Low-risk GTN was more aggressive in Asian women, who were significantly more likely to need second line chemotherapy and a higher number of chemotherapy regimens to achieve complete remission than women of African American and Asian descent. Further studies involving racial differences related to clinical, biological and environmental characteristics are needed. (C) 2015 Published by Elsevier Inc.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)