目的 探讨口腔医学专业本科生临床前期手卫生理论教学和实践训练模式.方法 将同一年级口腔医学专业本科生分为2组,试验组学生通过教师课堂教学形式学习手卫生知识后参加理论考试和洗手考核,对照组未经课堂学习手卫生知识直接进行理论考试和洗手考核.洗手采样和结果评价按照GB15982-2012《医院消毒卫生标准》,洗手训练采用PDCA循环管理体系进行监测.结果 2组学生在性别和学制上成绩比较,差异均有统计学意义(P＜0.05).试验组学生知晓洗手、卫生手和外科手的概念和指征、手卫生消毒的标准均明显高于对照组,差异均有统计学意义(P＜0.05).但2组学生手卫生具体方法上的知晓率比较,差异无统计学意义(P＞0.05).2组学生在性别和学制上比较,第3次明显高于第1次,差异有统计学意义(P＞0.05).结论 口腔医学专业本科生临床前期纳入手卫生学习和训练很有必要,应将手卫生原则和指征进行重点教学,手卫生训练需经PDCA循环反复实践才能达到理想的效果.
Objective: To study the composition and microstructure of the surface reaction layer of titanium castings into Al2O3-based investment materials.Methods: The composition,microstructure and hardness of the surface reaction layer of titanium castings were observed by SEM and TEM.Results: There were two layers on the surface of titanium castings,with outer layer being oxide layer including Al2O3,MgO,Al2TiO5(Al2O3·TiO2) and TixOy,and inner layer being alloy layer including Ti3Al and Ti.Conclusion: The formation mechanism of the surface reaction layer of titanium castings is that,when molten titanium is cast into Al2O3-based casting mould,Al2O3 dissolves into molten titanium by the form of atomic Al and O,Ti3Al and TixOy are separated out when the melt solidifies.
Procera系统是目前临床较常用的CAD/CAM系统。本文就CAD方面,在具体应用Procera Forte扫描仪和软件的1000多案例的口腔修复体设计过程中,包括扫描设计冠桥、贴面和种植体的单个蜡型基台过程中分别遇到的一些常见问题,通过截图的形式进行表述,并提出了相应的处理对策。
Objective:To evaluate ProTaper and Mtwo Instruments in curved Root Canals Preparation.Method:A total of 171 molars treated by root canal therapy were randomly assigned to three groups: ProTaper group,Mtwo group and K group.Wearing and tearing degree of equipment,preparation time and postoperative pain of 3 groups were also compared.Result:The average root canal preparation time of the Mtwo group was 5.4 min,significantly less than the ProTaper(6.8 min) group and the K(13.6 min).In three groups,root canals of ProTaper group and Mtwo group,could maintain the root canal anatomy in early form,and achieved good preparation results.Conclusion:Two nickel-titanium systems tested in this study are effective in the curved root canal preparation.The Mtwo instrument is much easier and faster during preparation with routine preparation technique.
