Extraction of the lower third molar is one of the most common procedures performed in oral surgery. In general, impacted tooth extraction involves sectioning the tooth’s crown and roots. In order to divide the impact...Extraction of the lower third molar is one of the most common procedures performed in oral surgery. In general, impacted tooth extraction involves sectioning the tooth’s crown and roots. In order to divide the impacted tooth so that it can be extracted, high-speed air turbine drills are frequently used. However, complications related to air turbine drills may occur. In this report, we propose an alternative tooth sectioning method that obviates the need for air turbine drill use by using a low-speed straight handpiece and carbide bur. A 21-year-old female patient presented to the institute’s dental hospital complaining of symptoms localized to the left lower third molar tooth that were suggestive of impaction. After physical examination, tooth extraction of the impacted left lower third molar was proposed and the patient consented to the procedure. The crown was divided using a conventional straight low-speed handpiece and carbide bur. This carbide bur can easily cut through the enamel of crown. On post-operative day number five, suture was removed and the wound was extremely clear. This technique could minimise intra-operative time and reduce the morbidity associated with air turbine drill assisted lower third molar extraction.展开更多
A new technology,semi-solid casting(thixocasting) method,was used to replace the conventional hot forging process to form AISI420 stainless steel air-turbine blade.The power law cut-off(PLCO) material model in Procast...A new technology,semi-solid casting(thixocasting) method,was used to replace the conventional hot forging process to form AISI420 stainless steel air-turbine blade.The power law cut-off(PLCO) material model in Procast software was used to simulate the thixocasting process.The thixocasting process was simulated.The results show that the reasonable technology parameters for air-turbine blade thixocasting process are obtained:billet temperature 1 483-1 485 °C,piston velocity 12-15 m/s and die temperature is about 400 °C.展开更多
牙科手机作为口腔诊疗中用量最大且频率最高的设备,对其进行全面统筹管理至关重要。该文以浙江大学医学院附属口腔医院为例,从单个牙科手机故障点着手分析,通过统计、对比各个院区牙科手机平均无故障连续使用次数(Mean Time Between Fai...牙科手机作为口腔诊疗中用量最大且频率最高的设备,对其进行全面统筹管理至关重要。该文以浙江大学医学院附属口腔医院为例,从单个牙科手机故障点着手分析,通过统计、对比各个院区牙科手机平均无故障连续使用次数(Mean Time Between Failure,MTBF),发现新开业的华家池总院牙科手机故障率明显异常,进而对牙科手机在医院的使用、流通过程进行了梳理,对其中可能产生问题的环节,协同各部门逐一分析,找到根本原因并采取相应措施。后续通过院区间MTBF对比,各院区牙科手机故障率接近,证明该问题得到解决。展开更多
文摘Extraction of the lower third molar is one of the most common procedures performed in oral surgery. In general, impacted tooth extraction involves sectioning the tooth’s crown and roots. In order to divide the impacted tooth so that it can be extracted, high-speed air turbine drills are frequently used. However, complications related to air turbine drills may occur. In this report, we propose an alternative tooth sectioning method that obviates the need for air turbine drill use by using a low-speed straight handpiece and carbide bur. A 21-year-old female patient presented to the institute’s dental hospital complaining of symptoms localized to the left lower third molar tooth that were suggestive of impaction. After physical examination, tooth extraction of the impacted left lower third molar was proposed and the patient consented to the procedure. The crown was divided using a conventional straight low-speed handpiece and carbide bur. This carbide bur can easily cut through the enamel of crown. On post-operative day number five, suture was removed and the wound was extremely clear. This technique could minimise intra-operative time and reduce the morbidity associated with air turbine drill assisted lower third molar extraction.
基金Project(50375117) supported by the National Natural Science Foundation of China
文摘A new technology,semi-solid casting(thixocasting) method,was used to replace the conventional hot forging process to form AISI420 stainless steel air-turbine blade.The power law cut-off(PLCO) material model in Procast software was used to simulate the thixocasting process.The thixocasting process was simulated.The results show that the reasonable technology parameters for air-turbine blade thixocasting process are obtained:billet temperature 1 483-1 485 °C,piston velocity 12-15 m/s and die temperature is about 400 °C.
文摘牙科手机作为口腔诊疗中用量最大且频率最高的设备,对其进行全面统筹管理至关重要。该文以浙江大学医学院附属口腔医院为例,从单个牙科手机故障点着手分析,通过统计、对比各个院区牙科手机平均无故障连续使用次数(Mean Time Between Failure,MTBF),发现新开业的华家池总院牙科手机故障率明显异常,进而对牙科手机在医院的使用、流通过程进行了梳理,对其中可能产生问题的环节,协同各部门逐一分析,找到根本原因并采取相应措施。后续通过院区间MTBF对比,各院区牙科手机故障率接近,证明该问题得到解决。
