Gold热处理镍钛锉在模拟S形根管内的抗疲劳折断性能  

Cyclic fatigue resistance of nickel-titanium files made by Gold heat treatment in simulated S-shaped root canals at different temperatures

作　　者：陈文新 侯晓玫[1] CHEN Wenxin;HOU Xiaomei(Second Clinical Division,Peking University School and Hospital of Stomatology&National Center for Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Research Center of Oral Biomaterials and Digital Medical Devices,Beijing 100101,China)

机构地区：[1]北京大学口腔医学院·口腔医院第二门诊部,国家口腔医学中心,国家口腔疾病临床医学研究中心,口腔生物材料和数字诊疗装备国家工程研究中心,北京100081

出　　处：《北京大学学报(医学版)》2025年第1期136-141,共6页Journal of Peking University:Health Sciences

基　　金：北京市自然科学基金(L242135);国家重点研发计划政府间国际科技创新合作项目(2024YFE0107100)。

摘　　要：目的:比较不同温度下3种新型热处理镍钛锉在模拟S形根管内的抗疲劳折断性能,为临床应用提供依据。方法:选取Gold热处理镍钛锉TruNatomy[25 mm长,26号/0.04锥度(尖段)]与ProTaper Gold[25 mm长,25号/0.08锥度(尖段)]作为实验组,M丝技术镍钛锉ProTaper Next[25 mm长,25号/0.06锥度(尖段)]作为对照组,每种镍钛锉各20支。TruNatomy镍钛锉经过Gold热处理使R相变分离,存在完全的中间R相,使柔软度提高;ProTaper Gold镍钛锉为CM丝镍钛锉,用热处理提高相变温度,常温下以马氏体为主,使柔软度提高,表面经Gold热处理产生中间R相;ProTaper Next镍钛锉则采用M丝技术,M丝常温下以奥氏体为主,经过热机械处理引入硬化马氏体,此类马氏体不参与相变,其弹性模量低于奥氏体,从而使镍钛锉柔软度增高。使用双弯金属模拟根管,分别在室温(24℃)及加热至65℃时检测3种镍钛锉的抗疲劳折断性能,不同温度下的每种镍钛锉各10支(n=10)。对相同温度下不同镍钛锉的疲劳折断圈数(number of cyclic fatigue,NCF)以及折断段长度数据采用单因素方差分析,并进行组间比较,以双侧P<0.05为差异有统计学意义。对相同镍钛锉不同温度下的NCF以及折断段长度数据采用配对样本t检验,并进行两两比较,检验水准均为双侧α=0.05。用扫描电镜进行折断镍钛锉断口分析。结果:3种镍钛锉均为在根尖弯曲处首先发生折断,随后在冠方弯曲处发生折断。室温下,根尖段NCF:Tru-Natomy镍钛锉为344.4±96.6,ProTaper Gold镍钛锉为175.0±56.1,ProTaper Next镍钛锉为133.3±39.7,TruNatomy镍钛锉最高(P<0.05);冠方段NCF:TruNatomy镍钛锉为618.3±75.3,ProTaper Gold镍钛锉为327.5±111.8,ProTaper Next镍钛锉为376.6±67.9,TruNatomy镍钛锉仍为最高(P<0.05)。根尖及冠方折断段长度各组间差异无统计学意义(P>0.05)。加热至65℃,根尖段NCF:TruNatomy镍钛锉为289.6±65.8,ProTaper Gold镍钛锉为187.5±75.4,ProTaper Next镍�Objective:To compare the cyclic fatigue resistance of nickel-titanium files made by 3 new heat treatment in simulated S-shaped root canals at different temperatures.Methods:Gold heat-treated nickel-titanium files TruNatomy(25 mm,tip size 26#/0.04)and ProTaper Gold(25 mm,tip size 25#/0.08)were selected as the experimental group,M wire technique nickel-titanium file ProTaper Next(25 mm,tip size 25#/0.06)was selected as the control group.It was speculated that the Gold technique used in TruNatomy nickel-titanium file was R phase separation technique,which included a complete intermediate R-phase,increasing its flexibility.ProTaper Gold was a CM wire nickel-titanium file and the increased phase transformation temperature by heat treatment introduced martensite at room temperature,while it underwent gold heat treatment on the surface,generating an intermediate R phase during phase transformation,providing hyperelastic.ProTaper Next used M wire technique,M wire included austenite at room temperature,where heat mechanical processing introduced hardened martensite,which was incapable of participating phase transformation.Because of the lower elastic modulus of hardened martensite than austenite,the flexibility of the file was increased.Twenty instruments of each nickel-titanium file were submitted to the cyclic fatigue test by using a simulated canal with double curvatures at room tem-perature(24℃)and 65℃,10 instruments of each nickel-titanium file were selected at each temperature(n=10).At the same temperature,the number of cyclic fatigue(NCF)and fragment length were analyzed by using One-Way analysis of variance at a significance level of P<0.05.NCF and fragment length of the same nickel-titanium file at room temperature and 65℃were compared by paired sample t test and the significance level wasα=0.05.Fractured surfaces were analyzed by using scanning electron microscope.Results:In double-curved canals,all the failure of the files due to cyclic fatigue was first seen in the apical curvature before the coronal cu

关 键 词：镍钛根管锉 S形根管 抗疲劳折断性能 热处理 

分 类 号：R781.3[医药卫生—口腔医学]