环氧乙烷对牙科手机灭菌效果及机械性能影响的实验研究

目的 探讨环氧乙烷对人工污染牙科手机灭菌效果和机械性能的影响.方法 采用实验室代表菌种污染牙科手机,经环氧乙烷气体灭菌后,无菌检查法检查牙科手机的灭菌效果,用酶联免疫吸附实验(ELISA)法检测HBsAg;牙科手机每经20次灭菌后进行机械性能检测.结果 环氧乙烷灭菌法对实验室污染的牙科手机可全部达到灭菌效果,乙型肝炎表面抗原(HBsAg)抗原性全部灭活;经200次灭菌后10支牙科手机中,2支转速下降至30万r/min以下,仍高于16万r/min的标准转速.结论 牙科手机用环氧乙烷灭菌效果可靠,并可满足机械的使用性能.     

五种灭菌器对牙科手机灭菌效果的研究

目的检测5种灭菌器对牙科手机的灭菌效果.方法用酶联免疫吸附(ELISA)法检测5种压力蒸汽灭菌器灭菌后的HBsAg人为污染的牙科手机,并对5种灭菌器灭菌后的临床污染的牙科手机进行无菌检测,同时用嗜热脂肪杆菌芽胞检测5种压力蒸汽灭菌器的灭菌效果.结果 5种灭菌器生物监测均合格,5种压力蒸汽灭菌器杀菌效果都可达100%,其中2种灭菌器灭菌的所有牙科手机HBsAg抗原性检测均为阴性,其他3种灭菌器灭菌的牙科手机各有1支HBsAg抗原性检测为阳性.结论压力蒸汽灭菌器效果可靠,乙肝病毒是否灭活,还需做其他检测.牙科手机应严格遵守灭菌保养流程,灭菌后应洁净存放.     

B级脉动真空压力蒸汽台式灭菌器对牙科手机灭菌效果分析

目的探讨B级脉动真空压力蒸汽台式灭菌器对牙科手机的灭菌效果。方法分析牙科手机灭菌器的选择、灭菌处理流程及灭菌效果监测,并对监测结果及牙科手机有效的灭菌方法进行评价。结果四川大学华西口腔医院采用B级脉动真空压力蒸汽台式灭菌器对牙科手机进行灭菌处理,其化学监测、生物监测指标均符合要求,灭菌有效率100%;对灭菌后牙科手机进行需氧培养、厌氧培养、乙型肝炎标志物监测均为阴性。结论对牙科手机采用B级台式灭菌器脉动真空压力蒸汽灭菌是行之有效的方法。     

牙科手机清洗及消毒方法研究

在口腔疾病诊断治疗过程中，口腔器械污染严重、尤以最常用的牙科手机的污染最为严重。我国目前尚无牙科手机灭菌标准，各个医院采取的消毒与灭菌方法有所不同，有些处理后器械未达到灭菌标准。另外，在选择牙科手机灭菌方法的同时还要考虑尽量减少多次灭菌后对其机械性能的损害，这     

戊二醛对牙科手机灭菌效果的实验室评价

目的:探讨碱性戊二醛(Cidex)对人工污染牙科手机的灭菌效果.方法:将人工污染牙科手机分别浸泡在0.5%、1%和2%的碱性戊二醛消毒液中,作用不同时间后放入中和剂中和10分钟取出,将浸泡处理后的牙科手机放入洗脱液中洗脱震荡40秒,对洗脱液进行检测.结果:0.5%、1%碱性戊二醛(Cidex)浸泡处理污染牙科手机4小时及2%碱性戊二醛(Cidex)浸泡处理污染牙科手机2小时,HBsAg灭活率均为100%;2%碱性戊二醛浸泡污染牙科手机10小时,对牙科手机上污染的枯草杆菌黑色变种芽孢菌的平均杀灭率为99.99%;2%碱性戊二醛浸泡污染牙科手机10小时,对灭菌处理后牙科手机进行无菌检查,其中有9支无菌检查合格、1支检菌仍为阳性.结论:2%Cidex浸泡处理污染牙科手机可完全破坏HBsAg抗原性,用2%Cidex浸泡处理临床污染牙科手机可作为杜绝口腔科器械HBsAg医源性传播的主要措施之一.     

牙科手机清洗中存在的问题与对策

目的：为预防口腔治疗中的交叉感染，探讨牙科手机清洗的有效方法。方法：找出目前牙科手机清洗中存在的问题，采取相应的措施。结果：口腔热清洗／消毒机的应用，对污染的牙科手机进行外部与内腔的自动化清洗消毒，是目前较好的清洗方法。结论：灭菌前的有效清洗，是确保牙科手机灭菌效果的关键。     

两种消毒方法对牙科手机灭菌效果的评价

目的 :比较含氯消毒剂浸泡法和环氧乙烷气体灭菌法对牙科手机的灭菌效果。方法 :利用枯草杆菌黑色变种芽孢和乙肝表面抗原阳性血清污染牙科手机 ,消毒后进行定量杀菌实验 ,用酶联免疫吸附实验 (ELISA)法检测HBsAg 结果 :牙科手机浸泡在有效氯含量为 30 0 0× 10 -6的消毒剂中 30分钟 ,细菌杀灭率及乙肝表面抗原的抗原灭活率均未达到 10 0 % ,而环氧乙烷灭菌法可达到 10 0 %。结论 :环氧乙烷灭菌牙科手机效果可靠。     

两种压力蒸汽灭菌器多次高压灭菌对镍钛锉表面形貌影响的AFM研究

目的：评价两种高压灭菌法对镍钛根管锉表面形貌的影响。方法：选择6支同一批次手动Protaper镍钛根管锉,分为两组,分别用两种灭菌方法经10次灭菌程序后在原子力显微镜（AFM）下观察,从距尖端6 mm范围内的20个不同的点,评价样本的粗糙度均方根,将此6支锉未经消毒时设为对照组。结果：所有参数均显示经预真空压力蒸汽灭菌器消毒组镍钛锉粗糙度大于对照组,而快速压力蒸汽灭菌器消毒组与对照组相比粗糙度相差不明显。结论：在保证灭菌效果的前提下,从延长器械使用寿命考虑,快速高压蒸汽灭菌是镍钛锉理想的灭菌方式。     

口腔材料与器械

国产碳纤维桩的固位力实验；MTT法评价国产碳纤维桩材料的细胞毒性；五种牙本质粘接剂体外细胞毒性研究；环氧乙烷对牙科手机灭菌效果及机械性能影响的实验研究；不同材料根管桩剪切粘结强度的比较；树脂透明牙模型用于根管治疗操作训练的效果评价；反向沉淀法制备牙科纳米氧化锆粉体；口腔修复常用合金稳态电位的测定；三种金属处理剂对金属与复合树脂间剪切粘接强度影响的研究。[编者按]     

选择高温高压蒸汽灭菌器的注意事项

选择高温高压蒸汽灭菌器时要注意以下事项： 1要有预真空功能，最佳方案是采用立体杀菌式灭菌器 具备预真空功能的灭菌器（B级或S级）可以通过预真空将中空器械里的空气团排出器械内腔，确保高温高压蒸汽迅速杀灭中空器械内外部的细菌，适用于手机和三用枪管等齿科器械的灭菌。此外立体杀菌能快速且精密定量控制，大大减少灭菌对涡轮手机的损伤。     

Autoclave sterilization of dental handpieces: A literature review

PurposeThe present review aimed to investigate autoclave sterilization of dental handpieces based on available studies.Study selectionThe sterilizing efficiency of dental handpieces with autoclave is mainly affected by the types of apparatus (N, B, and S), the packaging with sterilizing pouch, cleaning, and lubrication. These subjects were reviewed based on the in vitro experimental studies.ResultsDental handpieces can be sterilized, including inactivation of heat-resistant bacterial spores, with type B or type S sterilizers, regardless of the use of a sterilization pouch. In contrast, although type N autoclaves are capable of sterilization of general bacteria such as Streptococcus salivarius even in a sterilization pouch if instruments are washed beforehand, complete sterilization of the wrapped handpiece is not always achieved. Therefore, to achieve sterilization efficiency with type N autoclaves, processing without any packaging is recommended. As regards cleaning of handpiece, although contamination decreases with irrigation and wiping of handpieces, all reports concluded that these treatments alone do not achieve complete decontamination of reusable handpieces.ConclusionAlthough type B and type S autoclaves allow us to sterilize the dental handpieces, it is important to realize that complete sterilization of the handpiece is not always achieved by type N autoclave. Understanding autoclave processing of handpieces is essential for dental practice to deliver the safe dental care.     

Effect of steam sterilization inside the turbine chambers of dental turbines

OBJECTIVE: It has been demonstrated that contamination of the insides of high-speed dental turbines occurs and that bacteria as well as viruses may remain infectious when expelled from such turbines during subsequent use. Consequently, it has been widely recommended that a high-speed turbine be sterilized after each patient. The purpose of this study was to evaluate the effect of steam autoclaving on a high-speed dental turbine with a contaminated turbine chamber. STUDY DESIGN: Streptococcus salivarius and endospores of Bacillus stearothermophilus were used as test organisms to determine the effectiveness of 4 different small non-vacuum autoclaves and one vacuum autoclave. RESULTS: The study demonstrated different efficiencies among the small non-vacuum autoclaves, the best showing close to a 6 log reduction of the test organisms inside the turbine chamber. When cleaning and lubrication of the high-speed dental turbine was carried out before autoclaving, this level of reduction was observed for all the examined non-vacuum autoclaves. CONCLUSIONS: It is concluded that cleaning before sterilization is essential for safe use of high-speed dental turbines and that small non-vacuum autoclaves should be carefully evaluated before being used for the reprocessing of hollow instruments such as high-speed turbines.     

Influence of number of dental autoclave treatment cycles on rotational performance of commercially available air-turbine handpieces

The influence of number of autoclave treatment cycles (N) on rotational speed and total indicated run-out of commercially available air-turbine handpieces from five manufacturers was investigated at N=0, 50, 100, 150, 200, 250 and 300 cycles, and the significance in the test results was assessed by Dunnett's multiple comparison test. Some air-turbine handpieces showed the significant differences in rotational speed at N=300 cycles, however, the decreases of the rotational speeds were only 1 to 3.5 percent. Some air-turbine handpieces showed the significant differences in total indicated run-out, however, the respective values were smaller than that at N=0 cycle. Accordingly, it can be considered that the ball bearing in the air-turbine handpieces is not affected significantly by autoclave. To further evaluate rotational performance, this study focused on the rotational vibration of the ball bearing components of the air-turbine, as measured by Fast Fourier Transform (FFT) analysis; the power spectra of frequency of the ball's revolution, frequency of the cage's rotation and frequency of the ball's rotation were comparatively investigated at N=0, 150 and 300 cycles, and the influence of autoclave was evaluated qualitatively. No abnormalities in the ball bearings were recognized.     

一次性口腔高速涡轮手机的研制

目的　研制一次性口腔高速涡轮手机。方法　通过分析使用一次性口腔高速手机对于防止医源性交叉感染的重要意义 ,指出目前口腔临床治疗中所使用的高速手机存在的主要问题。提出了一种创新性的一次性口腔高速涡轮手机的的设计和制造方案。结果　设计出符合人体工程学的一次性口腔高速涡轮手机 ,并对其进行空气动力学分析 ,同时制定出一次性口腔高速涡轮手机所应符合的 7项主要技术指标。结论　新研制的口腔高速涡轮手机性能达到了口腔临床使用的要求。     

Performance of high-speed dental handpieces subjected to simulated clinical use and sterilization.

BACKGROUND: The authors investigated the performance of nine commercially available high-speed air-turbine dental handpieces subjected to 1,000 simulated clinical uses and sterilizations. METHODS: Six new handpieces from each of nine different models were subjected to simulated clinical use with a custom-made handpiece wear tester and then autoclaved. Ten parameters related to clinical performance (longevity, power, turbine speed, fiberoptic transmission, eccentricity, noise, chuck performance, visibility angle, interocclusal clearance and water coolant spray pattern) were measured at baseline and after 250, 500, 750 and 1,000 use/sterilization cycles. RESULTS: Power, turbine speed, eccentricity and noise performance were statistically analyzed using one-way analysis of variance and Turkey post hoc pairwise comparison tests at the .05 significance level. At baseline, significant differences were found between models for all of these parameters. In general, from baseline to 1,000 cycles, the handpieces exhibited greater eccentricity and reduced fiberoptic performance. Longevity data analyzed by using Gehan's generalized Wilcoxon test for comparison of survival distributions (alpha = .05) revealed significant differences between the handpiece models. CONCLUSIONS: The results of this study indicate that no handpiece model is superior to the others in all parameters evaluated. All models evaluated can be expected to perform for at least 500 clinical use/sterilizations, or approximately one year, if properly maintained. CLINICAL IMPLICATIONS: Clinicians need to be able to identify handpieces that can withstand repeated heat sterilization without loss of performance or longevity. The results of this study will aid clinicians in selecting handpiece models that meet their needs.     

Steam sterilization of air turbine dental handpieces

The efficacy of autoclaving high-speed dental handpieces was tested in two types of downward displacement steam sterilizers (instrument autoclaves), commonly used in the dentist's office. Eight series of experiments were performed with various sterilization schedules. Lubrication oils with or without antimicrobial agent were used in four of the series. Each handpiece was inoculated with 1 ml of a suspension containing equal amounts of saliva and spores of Bacillus stearothermophilus (approx. 10(6) spores/ml). Neither sterilization at 120-124 degrees C for 20 min nor at 134-136 degrees C for 10 min resulted in complete inactivation of the spores in series in which the instruments were tested without oil or with oil containing no antimicrobial agent. However, when the handpieces were lubricated with oil containing isopropanol and formaldehyde and the schedule 134-136 degrees C/10 min was used, no growth was observed. The results indicate that instrument autoclaves with built-in programs of 120-124 degrees C/20 min and 134-136 degrees C/10 min could have insufficient capacity to sterilize lubricated or unlubricated dental handpieces. The use of oils containing an antimicrobial agent can overcome this problem.     

A study of the use of autoclave bags in non-vacuum autoclaves

Two types of autoclave bags have been tested in five commonly used dental, non-vacuum autoclaves. The bags did not prevent the sterilization of instruments provided that most of the air was removed and the bags of instruments were not stacked. The use of a sterilization indicator in the bag is mandatory.     

三种灭菌法对高速裂钻腐蚀和切削率的影响

目的:观察湿热灭菌法、干热灭菌法、化学浸泡灭菌法处理高速裂钻后其表面腐蚀情况,以及对高速裂钻切削率的影响。方法:100根新高速裂钻随机分成10组分别用3种灭菌方法处理5、10、15次,体视显微镜观察处理前后裂钻表面形态的变化,参考Siegel标准自制设备测试裂钻的垂直和侧向切削率,统计分析灭菌处理对切削率的影响。结果:3种灭菌方法中,湿热灭菌法引起的裂钻表面腐蚀最严重;干热法最轻;湿热灭菌法引起的裂钻切削率下降幅度最明显,化学浸泡法、干热法次之。灭菌次数与腐蚀程度、切削率的降低幅度成正比,处理15次后,裂钻的垂直和侧向切削率均有明显下降。结论:湿热灭菌法引起的裂钻腐蚀改变最明显、切削率降低幅度最大,化学浸泡法、干热法较轻,建议牙用高速裂钻类小器械采用玻璃珠灭菌器进行灭菌。