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Saito CT Luvizuto ER Bosco AF Goiato MC Panzarini SR 《The Journal of craniofacial surgery》2012,23(2):e112-e115
A common finding in patients with edentulous maxilla and partially dentate mandible is mainly the presence of flabbiness in the anterior edentulous alveolar ridge that can compromise the retention and stability of a denture. Thus, this case report presents the correction of a flabby ridge, using an auxiliary technique combining surgical excision and autogenous connective tissue grafting. The technique improved the quality of the osteomucosal support of the alveolar ridge and increased the vestibule deepness, whose result increased the success rate of the new conventional total prosthesis. 相似文献
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Objective
The present work evaluated the thermal behavior of porcelain–metal and porcelain–zirconia restorations during fast and slow firing and cooling.Methods
All-ceramic (porcelain on zirconia) and porcelain-fused-to-metal (PFM) molar crowns were fabricated with 1 or 2 mm porcelain thickness. Thermocouples were attached to the cementation (T1) and occlusal (T4) surfaces of the restoration and embedded at the framework–porcelain interface (T2) and inside the porcelain (T3) to acquire temperature readings by time. Slow heating was set as 45 °C/min and fast heating as 140 °C/min. For fast cooling, the furnace was opened immediately after the holding time. Slow cooling was effected by opening the furnace when it reached 50 °C below the Tg. Porcelains Tg were calculated for each cooling rate.Results
Slow heating rate was measured at T4 as being 30 °C/min while fast heating at T4 was 100 °C/min. The measured cooling rates within the porcelain (T2) around the Tg range were 20 °C/min and 900 °C/min for slow and fast cooling, respectively. During slow cooling, similar temperatures were found for both zirconia and metal crowns. Remarkable temperature gradients were observed for the fast cooled all-ceramic crown (T1–T4 = 100 °C) and, of lower magnitude for PFM (T1–T4 = 30 °C). Tg of porcelains increase with faster cooling rates.Significance
Slow cooling appears to be especially important for all-ceramic crowns to prevent high magnitude thermal gradients, which could influence cracking and fracture of the porcelain. 相似文献55.
Although the terms "metabolic memory" and "legacy effect" have been used to describe the prolonged benefits of good blood glucose control, the former is now recognized as a phenomenon related to the prolonged harm produced mainly by hyperglycemia. At least three randomized clinical trials (Diabetes Control and Complications Trial in type 1 diabetes, United Kingdom Prospective Diabetes Study and Steno-2 in type 2 diabetes) have demonstrated that patients treated intensively for a period of time have a lower risk of micro- and macrovascular complications that persists during subsequent follow-up, even after their tight control has relented and the levels of glycated hemoglobin in the conventionally treated group improve. The mechanisms are not fully understood but most probably relate to the physiopathology of vascular complications of diabetes, and in recent years a unifying theory has been emerging to understand them. The excess superoxide anion produced by the mitochondria in response to hyperglycemia leads through disturbances at the nuclear level to the accumulation of potentially harmful substances such as advanced glycated end-products, protein kinase C, and nuclear factor κB, which are directly implicated in the development of vascular complications in diabetes. These adverse effects are not reversed when the high blood glucose is corrected, and some may be permanent because of epigenetic changes. Some antidiabetes drugs and antioxidant substances have produced partial reversibility of the mechanisms involved in the metabolic memory at the experimental level, but probably the best strategy is to optimize the metabolic control as early as possible, even before diabetes is diagnosed. 相似文献
56.
Leise R. Knoepp Kelly C. McDermott Alvaro Muñoz Joan L. Blomquist Victoria L. Handa 《International urogynecology journal》2013,24(5):735-740
Introduction and hypothesis
Benign joint hypermobility syndrome may be a risk factor for pelvic floor disorders. It is unknown whether hypermobility impacts the progress of childbirth, a known risk factor for pelvic floor disorders. Our objective was to investigate the association between joint hypermobility syndrome, obstetrical outcomes, and pelvic floor disorders. Our hypotheses were: (1) women with joint hypermobility are less likely to experience operative delivery and prolonged second-stage labor; and (2) pelvic floor disorders are associated with benign hypermobility syndrome, controlling for obstetrical history.Methods
Joint hypermobility was measured in 587 parous women (participants in a longitudinal cohort study of pelvic floor disorders after childbirth). Their obstetrical histories were obtained from review of hospital records. Pelvic floor disorders were assessed using validated questionnaires and a structured examination for prolapse. Joint hypermobility and pelvic floor disorders were evaluated at enrollment (5–10 years after first delivery). We compared obstetrical outcomes and pelvic floor disorders between women with and without joint hypermobility, defined as a Beighton score ≥4.Results
Hypermobility was diagnosed in 46 women (7.8 %) and was associated with decreased odds of cesarean after complete cervical dilation or operative vaginal delivery [odds ratio (OR)?=?0.51; 95 % confidence interval (CI):0.27–0.95]. Anal sphincter laceration was unlikely to occur in women with hypermobility (OR?=?0.19; 95 % CI 0.04–0.80). However, hypermobility was not associated with any pelvic floor disorder considered.Conclusions
Benign joint hypermobility syndrome may facilitate spontaneous vaginal birth but does not appear to be a risk factor for pelvic floor disorders in the first decade after childbirth. 相似文献57.
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William N. Evans Ruben J. Acherman Michael L. Ciccolo Sergio A. Carrillo Alvaro Galindo Abraham Rothman Brody J. Winn Noel S. Yumiaco Humberto Restrepo 《Pediatric cardiology》2016,37(7):1274-1277
We tested the hypothesis that MELD-XI values correlated with hepatic total fibrosis scores obtained in 70 predominately stable, post-Fontan patients that underwent elective cardiac catheterization. We found a statistically significant correlation between MELD-XI values and total fibrosis scores (p = 0.003). Thus, serial MELD-XI values may be an additional useful clinical parameter for follow-up care in post-Fontan patients. 相似文献