自增强可吸收内固定治疗儿童肘部骨折

目的评价自增强可吸收内固定治疗儿童肘部骨折的可行性和有效性。方法2002年7月-2003年12月，25例儿童肘部骨折应用自增强可吸收内固定螺钉或棒固定，对其手术方法、骨折愈合、功能恢复进行回顾性分析总结。结果平均随访时间18个月（10-24个月）。所有骨折均于4周内达到临床愈合。1例肱骨髁上骨折因可吸收棒穿于皮下引起疼痛，妨碍关节活动，于术后6周拔除，恢复良好。1例肱骨内上髁骨折予可吸收螺钉固定，为保持骨折复位稳定，术后伸肘位石膏固定3周致关节僵硬，经CPM被动活动锻炼后肘关节活动基本恢复正常。其余病例在最后一次随访时，均关节活动良好，无畸形发生，也未见局部无菌性反应。结论自增强可吸收内固定治疗儿童肘部骨折可靠有效，近期随访效果满意，术后可早期进行功能锻炼。     

数字曲面体层X片在评价非负荷期种植体周围骨吸收的临床应用

目的:评价数字曲面体层X片在测量非负荷期种植体周围牙槽骨吸收的应用情况。方法:观测、分析对比26例患者50枚Camlog系统种植体临床应用非负荷期间数字化曲面体层X片和X线牙片上种植体周围牙槽骨吸收的情况。结果:50枚Camlog种植体植入后10 d,两种X片骨吸收测量结果分别为0.65 mm、0.81 mm,两者之间无明显差异;第4个月(或6月\下颌)分别为0.12 mm、0.19 mm,两者之间无明显差异。结论:本研究显示数字化曲面体层X片在测量非负荷期种植体周围牙槽骨吸收的应用中有操作简单、重复性好、精确度高、变形可补偿等优点,有实际应用价值,值得推广。     

关节镜下可吸收性半月板箭治疗半月板损伤的初步报告

目的关节镜下应用可吸收性半月板箭治疗半月板损伤并评价其近期疗效。方法2002年2～10月,关节镜下采用半月板箭缝合固定12例12侧半月板损伤,男5例,女7例;年龄18～58岁,平均33.2岁。左膝4例,右膝8例。内侧半月板损伤4例,外侧半月板损伤8例;前角损伤2例,体部损伤3例,后角损伤7例。红区损伤10例,红-白区损伤2例。病程3d～5个月,平均2.3个月,其中急性损伤(病程<1个月)9例。关节镜下采用新型全内半月板箭技术固定,共使用25枚半月板箭(平均每例2.1枚)。5例同时施行其它类型手术。结果所有病例术后均无早期并发症发生。全部患者均获得随访,随访时间7～13个月,平均10.2个月。随访时所有患者膝关节稳定,无疼痛、绞锁等症状,6周后关节活动度全面恢复。Lysholm评分由术前的平均(45.6±13.4)分增加到术后平均(82.4±16.3)分,差异有显著性(P< 0.05)。2例分别于术后8个月和9个月出现关节积液,考虑为滑膜炎,经治疗后消失。结论对于半月板损伤,如撕裂类型和部位适当,可选择可吸收性半月板箭治疗。半月板箭技术是一种简便快捷、安全有效的半月板缝合方法。     

人发角蛋白桥接周围神经缺损的形态学观察

目的 :了解人发角蛋白在神经再生中的作用 ,为临床桥接周围神经缺损寻求新的替代材料。方法 :将 18只新西兰兔的双侧坐骨神经切断 ,造成 10mm缺损 ,一侧用人发角蛋白桥接 (实验组 ) ,另一侧用空硅胶管桥接 (对照组 ) ,术后 1、 2、 3个月通过肉眼观察 ,光镜、电镜和有髓神经密度测定 ,观察、分析神经再生情况。结果 :实验组再生神经均通过 10mm缺损 ,对照组有 2例无神经生长 ;实验组再生神经排列较紧密、有序 ,髓鞘形成早于对照组 ;神经纤维密度明显高于对照组 (P <0 0 1)。结论 :人发角蛋白可促进周围神经再生 ,是桥接周围神经缺损的理想材料。     

Intelligent dialogue based on statistical models of clinical decision-making

The independence Bayesian model has been used widely in computer programs designed to support clinical decision-making. A reasoning strategy has been developed to enable these programs to conduct clinically pertinent dialogue and explain their reasoning. It has been implemented in a program for the diagnosis of acute abdominal pain based on the Bayesian model of de Dombal et al. Several features of the dialogue design have been adopted from artificial intelligence research, including shared initiative and critiquing. The program adopts a flexible goal-driven strategy, attempting to confirm the clinician's diagnosis or rule out the likeliest alternative. Symptoms and signs are selected in order of their expected weights of evidence in favour of the hypothesized disease.     

An XPS and SEM evaluation of six chemical and physical techniques for cleaning of contaminated titanium implants

The purpose of the present study was to analyse clinically failed and retrieved implants prior to and after cleaning by means of scanning electron microscopy (SEM) and X-ray induced photoelectron spectroscopy (XPS) as compared to unused controls. Six different chemical and physical techniques for cleaning of contaminated titanium implants were evaluated: 1) rinsing in absolute ethanol for 10 min, 2) cleaning in ultrasonic baths containing trichloroethylene (TRI) and absolute ethanol, 10 min in each solution, 3) abrasive cleaning for 30 s, 4) cleaning in supersaturated citric acid for 30 s, 5) cleaning with continuous CO2-laser in dry conditions at 5 W for 10 s, 6) cleaning with continuous CO2-laser in wet conditions (saline) at 5 W for 10 s. SEM of failed implants showed the presence of contaminants of varying sizes and XPS showed almost no titanium but high carbon signals. XPS of unused titanium implants showed lower levels of titanium as previously reported, probably due to contamination of carbon which increased with time in room air. Cleaning of used implants in citric acid followed by rinsing with deionized water for 5 min followed by cleaning in ultrasonic baths with TRI and absolute ethanol gave the best results with regard to macroscopical appearance and surface composition. However, as compared to the unused implants the results from an element composition point of view were still unsatisfactory. It is concluded that further development and testing of techniques for cleaning of organically contaminated titanium is needed.     

FRACTURE OF ABUTMENT SCREW SUPPORTING A CEMENTED IMPLANT-RETAINED PROSTHESIS WITH EXTERNAL HEXAGON CONNECTION: A CASE REPORT WITH SEM EVALUATION

One of the causes of implant failures in cemented implant-retained prostheses is the fracture of abutment screw or UCLA abutment. This article reports a case of simultaneous fracture of two UCLA abutments screws occurring in an implant-supported prosthesis placed in the mandibular molar region. The fractured structures were examined under scanning electron microscopy to investigate the probable causes of the failure, which were not related to failures on materials or fabrication of the screws, but rather were due to shear forces. The misfit in cemented prostheses may be the most likely cause of shear force generation.     

儿童羟基磷灰石义眼台植入的临床分析

目的:观察儿童羟基磷灰石义眼台植入的临床效果。方法:回顾性分析不同原因造成眼球摘除的31例患儿,其中男性 21例,女性 10例,年龄 3岁～14岁,平均 8.2岁,采用义眼台一期植入 20例,义眼台二期植入 11例,植入直径 18mm义眼台者 17例,植入 20mm义眼台者 14例。结果:31例患儿术后 1例结膜裂开,5例出现轻度上睑沟凹陷,随访 1年～8年,所有患者无感染、无排斥、无义眼台暴露,运动好,外观满意。结论:儿童患者应尽可能一期植入义眼台,采用巩膜包裹义眼台植入的 3岁～6岁患儿选择 18mm直径的义眼台,而 7岁～14岁患儿尽量接近成人选用 20mm直径的义眼台。注意手术操作、术后用药及护理可减少术后并发症。