清洗时间和消毒灭菌频率对镍钛根管锉物理性能的影响

Influence of ultrasonic cleaning time and disinfecting frequency on physical property of Ni-Ti root canal files

目的探讨超声清洗时间和消毒灭菌频率对镍钛根管锉的物理性能的影响，以了解超声清洗和高温高压消毒灭菌法在镍钛根管锉灭菌中应用的安全性和可行性。方法实验对象为3种不同的镍钛根管锉（ProTaper、Mtwo、Hero642），每组各5支，经过超声振荡清洗和高温高压灭菌后进行折断实验，对照组为不清洗和未灭菌组。记录各组镍钛根管锉的折断时间并进行比较。结果ProTa．per和Mtwo镍钛根管锉经不同时间清洗，折断时间比较差异无统计学意义，而Her0642型根管锉经不同时间的清洗，折断时间比较差异有统计学意义。经不同频率的消毒灭菌后，Mtwo型镍钛根管锉的折断时间比较差异无统计学意义，而另两种折断时间比较差异有统计学意义。结论超声清洗时间对ProTaper、Mtwo型镍钛根管锉的物理性能无显著影响，而对Her0642型镍钛根管锉的物理性能影响显著。消毒灭菌频率对ProTaper和Her0642型根管锉的物理性能影响显著，而对Mtwo型的物理性能影响不显著。

Objective To investigate the influence of ultrasonic cleaning time and disinfecting frequen- cy on physical property of Ni- Ti root canal files in order to understand the safety and feasibility of ultrasonic cleaning and high temperature and high pressure disinfection for Ni-Ti root canal files. Methods The Ni-Ti root canal files used in this study were ProTaper, Mtwo and Hero642, 5 files were selected from each kind. After the ultrasonic cleaning and high temperature high pressure disinfection the files underwent breaking test, the breaking time was recorded. Unclean and non-sterile Ni-Ti root canal files were set as control. Results After different time of ultrasonic cleaning, ProTaper and Mtwo showed no difference in breaking time, but the result was opposite in Hero642. After different times of disinfection, Mtwo showed no difference in breaking time, but significant difference was seen in the other two kinds. Conclusions Ul- trasonic cleaning time has no significant influence on physical property of ProTaper and Mtwo Ni-Ti root canal files, but the influence was significant for Hero642. Disinfection frequency had no significant influence on physical property of ProTaper and Hero642 Ni-Ti root canal files, but the influence was significant for Mtwo Ni-Ti root canal files.