Biomechanical evaluation of maxillary Lefort Ι fracture with bioabsorbable osteosynthesis internal fixation

The aim of this study was to apply biomechanical analysis model to evaluate the effects of bioabsorbable internal fixation devices on maxillary Lefort Ι fracture. CT scan technology and the finite element software (ansys ) were used to establish three‐dimensional finite element models of five resorbable internal fixation devices in maxillary Lefort Ι fractures. We used the model to calculate the stress of the upper jaw and internal fixation. We further analyzed the stability of fixation under four occlusions. The fixation using two bioabsorbable plates was not stable. The zygomaticomaxillary pillars fixation is more stable than other fixations. The stability of fracture fixation was influenced with the molar occlusion. The current study developed a functional three‐dimensional finite element model of bioabsorbable internal fixation and compared the stability of five fixation methods for maxillary Lefort Ι fractures. The results would facilitate the application of bioabsorbable materials in dental clinic.     

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目的评价不同漂白方法对氟斑牙漂白的临床效果。方法轻中度氟斑牙患者30例随机分为3组,每组10例60颗牙。分别采用联合漂白、激光漂白、家庭漂白3种方法进行上前牙区漂白,在漂白前、漂白后即刻、漂白后1个月、漂白后1年记录其L＊a＊b＊值,比较3组漂白效果及颜色回复情况。应用统计学分析软件CS10.34对数据进行t’检验。结果 3组漂白后的L＊a＊b＊值与漂白前比较差异均有统计学意义（均P〈0.05）;漂白后1个月,联合组与激光组颜色有所回复（P〈0.05）;漂白后1年,联合组、激光组颜色与漂白后即刻相比有所回复（P〈0.05）,与漂白后1个月相比颜色回复差异无统计学意义（P〉0.05）;家庭组颜色回复差异无统计学意义,但1个月到1年期间颜色变化小于治疗后即刻到1个月的变化（P〈0.05）。结论 3种漂白方案治疗1个疗程都得到相似的美白效果,但短期内也出现漂白牙的颜色回复,家庭漂白颜色相对稳定,诊室漂白收效快,3种治疗方案各有其适应人群。     

三种洗手用品洗手效果比较

目的比较临床医护人员使用传统的肥皂、洗手液、无水洗手液三种洗手用品洗手的效果。方法分别对三种洗手用品的效果进行细菌学监测并作统计学分析。结果肥皂、洗手液、无水洗手液洗手后平均菌数分别为10．1cfu／cm^2、8．3cfu／cm^2和3．6cfu／cm^2。结论无水洗手液洗手效果优于传统的肥皂和洗手液,且方便、快速、高效,值得临床广泛推广。     

超声引导下深静脉穿刺置管技术在围术期小儿患者中的应用

目的：探讨超声引导下深静脉穿刺置管技术在围术期小儿患者中的应用效果。方法选取我院接收的80例择期拟行手术患儿作为本次的研究对象,对其临床资料进行回顾分析。结果观察组患儿的穿刺置管时间、穿刺总成功率、一次穿刺成功率、失败率及并发症发生率与对照组比较均有统计学差异（P ＜0.05）。结论给予择期手术患儿超声引导下深静脉穿刺置管术治疗可提高成功率,减少并发症,具有较高的应用价值,可推广应用。     

The clinical landmark of infraorbital foramen in Chinese population: a prospective measurement study

Background

Infraorbital nerve block can only be administered effectively with good knowledge of the location of the infraorbital foramen (IOF). In this article, we will describe the clinical landmark of the IOF with references to the infraorbital rim (IOR), mid-pupillary line (MPL), and facial midline (FML).

Methods

In our division, maxillary swing approach was adopted for the access of the nasopharynx and skull base. Through a Weber-Ferguson-Longmire incision, the maxilla was freed from its bony connections and swung out to expose the skull base. With this approach, the infraorbital foramen and nerve were identified under direct vision. Prospective measurements were taken intraoperatively on a series of patients who underwent maxillary swing operation. The distances between the IOF and various reference points (IOR, MPL, and FML) were measured with caliper. Means, standard deviations, and ranges were determined.

Results

From April 2009 to October 2012, 30 patients were included in this study. The locations of 30 infraorbital foramina were analyzed. The distances between IOF and IOR, MPL, and FML ranged from 8 to 12 (mean 9.6?±?1.3) mm, 4 to 14 (mean 9.3?±?2.4) mm, and 24 to 38 (mean 32.7?±?3.4) mm, respectively.

Conclusions

To our knowledge, this is the first study in the literature demonstrating the clinical landmark of IOF on living persons and adopting MPL as a reference point. We believe that the IOR and MPL are convenient reference points for the accurate localization of IOF. Level of Evidence: Level IV, diagnostic study.     

Diagnosing skin rejection in vascularized composite allotransplantation: advances and challenges

Refinements in microsurgical techniques coupled with advances in immunosuppressive and immunomodulatory protocols have enabled broader clinical application of vascularized composite allotransplantation (VCA) with encouraging immunological, functional, and esthetic results. However, skin rejection remains a significant obstacle and a serious complication for VCA recipients. Clinical and histopathological features of rejection in VCA have been described in a number of studies, which led to the development of an international consensus on the classification guidelines of rejection in the context of VCA. Nevertheless, currently available diagnostic modalities still have several limitations and shortcomings that can pose a significant diagnostic challenge, particularly when signs of rejection are found to be equivocal. In this review, we provide a critical analysis of these advances and challenges in diagnosing skin rejection. Specifically, we highlight the gaps in understanding of rejection mechanisms, the shortfalls in correlating cellular, molecular, and clinicopathologic markers with rejection grades, deficiencies in defining chronic rejection, and antibody‐mediated rejection after VCA, as well as providing an outlook on novel concepts, such as the utilization of advanced computational analyses and cross‐disciplinary diagnostic approaches.     

Risk factors for acute kidney injury (AKI) in infants with melamine-associated urolithiasis and follow-up: a multi-center retrospective analysis

An epidemic of urinary tract stones was noted among infants in China, 2008. This event was believed to be associated with consumption melamine-contaminated powdered formula. The patients with symptoms and clinical manifests had already been analyzed in our previous studies. In this study, our aim is to investigate the risk factors of melamine-associated acute kidney injury (AKI) and the potential relationship toward children growth in our five years follow-up. A total of 619 infants with melamine-associated urolithiasis were admitted into 20 different hospitals in the Gansu province, China. All clinical data were divided into AKI and control groups according to the occurrence of AKI. Univariate and multivariate analyses were performed with a logistic regression model to assess the independent risk factors of AKI. Logistic regression analysis revealed that the odds ratio (OR) of AKI was 19.62 in the group of infants who consumed Sanlu® milk powdered infant milk formula. A higher prevalence of AKI was observed in infants age of 6–11 months (OR: 9.59, p?p?p?相似文献   

不同前路内固定方式治疗枢椎椎体横行骨折合并Hangman骨折稳定性的有限元分析

【摘要】 目的：应用有限元分析评价三种C2~C3前路内固定方式治疗枢椎椎体横行骨折合并Hangman骨折的生物力学稳定性,为临床手术方式选择提供理论参考。方法：选择1位35岁健康男性志愿者,采用16排螺旋CT对枕骨底（C0）~C3节段进行层厚0.5mm的薄层扫描,利用Mimics 10.01、Hypermesh V 10.0及ABAQUS 6.11软件,建立正常颈椎C0~C3节段三维六面体网格有限元模型（FE/Intact）并进行有效性验证。在已验证的C0~C3节段模型上通过弱化网格单元强度的方法模拟建立枢椎椎体横行骨折合并Hangman骨折模型（FE/Fracture）并进行验证;在FE/Fracture上分别建立三种C2~C3前路内固定模型：前路C2/3椎间盘切除、cage植骨融合+长钢板螺钉内固定模型（FE/cage+ACFLP）;前路齿状突螺钉固定+C2/3椎间盘切除、cage植骨融合+短钢板螺钉内固定模型（FE/AOSF+cage+ACFSP）;前路齿状突螺钉固定+C2/3椎间盘切除、cage植骨融合+长钢板螺钉内固定模型（FE/AOSF+cage+ACFLP）,对FE/Intact、FE/Fracture和三种内固定模型进行边界约束后分别施加前屈、后伸、侧屈、旋转四种生理载荷,比较各模型在不同工况下三维活动的角位移（ROM）及骨折端节点位移变化。结果：建立的FE/Intact外观逼真,几何相似性好,经验证有效。在相同条件下FE/Fracture模型三维活动度较FE/Intact模型明显增大,在前屈、后伸、侧屈及旋转方向上的ROM分别增加至FE/Fracture模型的244.7％、203.3％、188.9％、200％;FE/AOSF+cage+ACFLP在前屈、后伸、侧屈、旋转方向上的ROM分别为FE/Intact的60.5％、70％、66.7％、62.5％;FE/AOSF+cage+ACFSP在各方向的ROM分别为FE/Intact的118.4％、123.3％、148.1％、175％;FE/cage+ACFLP在各方向上的ROM分别为FE/Intact的123.7％、143.3％、122.2％、137.5％。FE/AOSF+cage+ACFLP稳定性最强,骨折端位移最小;FE/AOSF+cage+ACFSP稳定性较差,其在侧屈和旋转方向上ROM及骨折端位移最大;FE/cage+ACFLP在前屈及后伸方向上提供的稳定性最差,骨折端的位移最大。结论：FE/AOSF+cage+ACFLP固定可为枢椎椎体横行骨折合并Hangman骨折提供较强的生物力学稳定性,达到固定融合C2~C3节段和骨折断端以重建上颈椎稳定性的目的。     

甲状腺疾病、糖尿病相关骨质疏松的病因研究进展

骨质疏松症是临床的常见病和多发病,并严重影响着人们的健康和生活质量,而糖尿病和甲状腺疾病都是继发性骨质疏松的主要病因。了解这两种疾病相关骨质疏松的病因对骨质疏松的治疗和预防有重要意义。本文主要对内分泌代谢病中的甲状腺疾病及糖尿病引起骨质疏松的病因进行了阐述。