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991.
Janaina Salmos Marleny E. M. M. Gerbi Rodivan Braz Emanuel S. S. Andrade Belmiro C. E. Vasconcelos Ricardo V. Bessa-Nogueira 《Lasers in medical science》2010,25(1):127-136
The purpose of this study was to identify systematic reviews (SRs) that compared laser with other dental restorative procedures and to evaluate their methodological quality. A search strategy was developed and implemented for MEDLINE, the Cochrane Library, LILACS, and the Brazilian Dentistry Bibliography (1966–2007). Inclusion criteria were: the article had to be an SR (± meta-analysis); primary focus was the use of laser in restorative dentistry; published in English, Spanish, Portuguese, Italian, German. Two investigators independently selected and evaluated the SRs. The overview quality assessment questionnaire (OQAQ) was used to evaluate methodological quality, and the results were averaged. There were 145 references identified, of which seven were SRs that met the inclusion criteria (kappa?=?0.81). Of the SRs, 71.4% appraised lasers in dental caries diagnosis. The mean overall OQAQ score was 4.4 [95% confidence interval (CI) 2.4–6.5]. Of the SRs, 57.1% had major flaws, scoring ≤4. SR methodological quality is low; therefore, clinicians should critically appraise them prior to considering their recommendations to guide patient care. 相似文献
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Estevam A. Bonfante Brian Rafferty Ricardo A. Zavanelli Nelson R. F. A. Silva Elizabeth D. Rekow Van P. Thompson Paulo G. Coelho 《European journal of oral sciences》2010,118(2):202-209
Bonfante EA, Rafferty B, Zavanelli RA, Silva NRFA, Rekow ED, Thompson VP, Coelho PG. Thermal/mechanical simulation and laboratory fatigue testing of an alternative yttria tetragonal zirconia polycrystal core‐veneer all‐ceramic layered crown design. Eur J Oral Sci 2010; 118: 202–209. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci This study evaluated the stress levels at the core layer and the veneer layer of zirconia crowns (comprising an alternative core design vs. a standard core design) under mechanical/thermal simulation, and subjected simulated models to laboratory mouth‐motion fatigue. The dimensions of a mandibular first molar were imported into computer‐aided design (CAD) software and a tooth preparation was modeled. A crown was designed using the space between the original tooth and the prepared tooth. The alternative core presented an additional lingual shoulder that lowered the veneer bulk of the cusps. Finite element analyses evaluated the residual maximum principal stresses fields at the core and veneer of both designs under loading and when cooled from 900°C to 25°C. Crowns were fabricated and mouth‐motion fatigued, generating master Weibull curves and reliability data. Thermal modeling showed low residual stress fields throughout the bulk of the cusps for both groups. Mechanical simulation depicted a shift in stress levels to the core of the alternative design compared with the standard design. Significantly higher reliability was found for the alternative core. Regardless of the alternative configuration, thermal and mechanical computer simulations showed stress in the alternative core design comparable and higher to that of the standard configuration, respectively. Such a mechanical scenario probably led to the higher reliability of the alternative design under fatigue. 相似文献
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Ricardo Ramina Mauricio Coelho Neto Andre Giacomelli Erasmo Barros Jr. Ronaldo Vosgerau Alessandra Nascimento Gisele Coelho 《Acta neurochirurgica》2010,152(1):27-33
Purpose
The goal of this study was to develop a method to reduce the costs of intraoperative high-field magnet resonance imaging (iMRI). The results of a series of 29 gliomas removed with this technique are presented. 相似文献995.
996.
Márcio Bruno Amaral Sebastião Cristian Bueno Alice Araújo Ferreira Silva Ricardo Alves Mesquita 《Dental traumatology》2011,27(3):235-240
Abstract – Superolateral dislocation of the intact mandibular condyle (SDIMC) is rare. This case report focuses on a 15‐year‐old teenager who was involved in a motor vehicle accident as well a literature review regarding the SDIMC. Clinical examination demonstrated a diffuse edema in the midfacial area and a left lateral deflection of the mandible, including an open bite and a crepitation in the symphyseal region. Three‐dimensional computed tomography scans were taken, which presented a superolateral dislocation of the left mandibular condyle as well as panfacial fracture. The patient was set in intermaxillary fixation for 2 weeks and underwent subsequent active jaw physiotherapy, the evaluation of which presented satisfactory results. This case study also presents a literature review, which demonstrated 21 well‐documented cases of SDIMC. The patients’ mean age was of 29 years. The male gender proved to be more prevalent, with road traffic collisions representing the most common form of accident. Type II, with unilateral dislocation, proved to be the most common. The mean reduction time was 7 days. The open methods were the most commonly used reduction methods. Mandible fracture was associated with dislocation in 82% of the cases, with other facial fractures appearing in only 23% of the cases. Patient follow up presented satisfactory results in 59% of the cases. 相似文献
997.
Michelle Lampl Juan Pedro Kusanovic Offer Erez Jimmy Espinoza Francesca Gotsch Luis Goncalves Sonia Hassan Ricardo Gomez Jyh Kae Nien Edward A. Frongillo Roberto Romero 《American journal of human biology》2009,21(2):141-150
The past two decades in the United States have seen a 24% rise in spontaneous late preterm delivery (34–36 weeks) of unknown etiology. This study tested the hypothesis that fetal growth was identical prior to spontaneous preterm (n = 221, median gestational age at birth 35.6 weeks) and term (n = 3706) birth among pregnancies followed longitudinally in Santiago, Chile. The hypothesis was not supported: Preterm‐delivered fetuses were significantly larger than their term‐delivered peers by mid‐second trimester in estimated fetal weight, head, limb, and abdominal dimensions, and they followed different growth trajectories. Piecewise regression assessed time‐specific differences in growth rates at 4‐week intervals from 16 weeks. Estimated fetal weight and abdominal circumference growth rates slowed at 20 weeks among the preterm‐delivered, only to match and/or exceed their term‐delivered peers at 24–28 weeks. After an abrupt growth rate decline at 28 weeks, fetuses delivered preterm did so at greater population‐specific sex and age‐adjusted birth weight percentiles than their peers from uncomplicated pregnancies (P < 0.01). Growth rates predicted birth timing: one standard score of estimated fetal weight increased the odds ratio for late preterm birth from 2.8 prior to 23 weeks, to 3.6 (95% confidence interval, 1.82–7.11, P < 0.05) between 23 and 27 weeks. After 27 weeks, increasing size was protective (OR: 0.56, 95% confidence interval, 0.38–0.82, P = 0.003). These data document, for the first time, a distinctive fetal growth pattern across gestation preceding spontaneous late preterm birth, identify the importance of mid‐gestation for alterations in fetal growth, and add perspective on human fetal biological variability. Am. J. Hum. Biol., 2009. © 2008 Wiley‐Liss, Inc. 相似文献
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