不同镍钛器械临床疗效的体外研究

Clinical efficacy of different nickel-titanium instruments:An in vitro study

目的:评价ProTaper Universal(PTU)、Reciproc Blue(RB)、VDW.ROTATE(VR)、葆丰蓝晶灵(葆丰)和ORODEKA-U系列(O-U)五种机用镍钛器械在中心定位能力、根尖碎屑溢出和牙本质微裂三方面的临床预备效果。方法:(1)中心定位实验:选取50个树脂根管(n=10),记录预备前后根管形态和预备时间,测量树脂去除量。(2)根尖碎屑溢出实验:选取50个单根管前磨牙(n=10),收集预备过程中溢出的碎屑并称重。(3)牙本质微裂实验:选取50个下颌磨牙(n=10),micro-CT扫描预备前后横截面图像。结果:(1)中心定位实验:5组预备时间有统计学差异(P<0.05),PTU组最长,RB组最短。PTU组距根尖孔1-3 mm处偏移显著大于其余4组(P<0.05);距根尖4 mm处O-U组较好,距根尖5-6 mm处VR组较好。(2)根尖碎屑溢出实验:RB组溢出碎屑最多(P<0.05),其余四组无明显差异(P>0.05)。(3)牙本质微裂实验显示,PTU、RB、VR和O-U组预备前后有显著性差异(P<0.05),葆丰组无明显差异(P>0.05)。结论:(1)在根尖段,PTU的中心定位能力欠佳;根管弯曲段,VR、O-U的中心定位能力相对较好。(2)RB的根尖溢出碎屑量最多。(3)葆丰预备后产生的微裂最少。

AIM:To evaluate the clinical efficacy of five Ni-Ti instruments,namely,ProTaper Universal(PTU),Reciproc Blue(RB),VDW.ROTATE(VR),Baofeng Lanjing(Baofeng)and ORODEKA-U series(O-U),with regard to their centering ability,apical debris extrusion,and dentinal microcracks.METHODS:①Centering ability:50 resin root canals(n=10)were selected,the morphology of the canals and the preparation time were recorded before and after the preparation,and the amount of resin removed was measured.②Apical debris extrusion experiment:50 single root canal premolars were selected(n=10),and the debris extruded in the process of the preparation was collected and weighed.③Dentinal microcrack:50 mandibular molars(n=10)were selected,the cross-section before and after preparation was scanned by micro-CT.RESULTS:①Centering ability:there was a statistically significant difference in the preparation time among the five groups(P<0.05),with the longest in the PTU group and the shortest in the RB group.1-3 mm from the apical foramen of the PTU group was significantly larger than that of the remaining four groups(P<0.05);4 mm from the apical foramen in the O-U group was better,and 5-6 mm from the apical foramen in the VR group was better.②Apical debris extrusion experiment:the largest amount of debris extruded from the RB group(P<0.05),and there was no significant difference among the remaining four groups(P>0.05).③Dentinal microcrack:there was a significant difference before and after preparation in the PTU,RB,VR,and O-U groups(P<0.05),and there was no significant difference in the Baofeng group(P>0.05).CONCLUSION:①In the apical segment,PTU had poor centering ability;in the curved segment of the root canal,VR and O-U had relatively good centering ability.②RB had the highest amount of apical extruded debris.③Baofeng produced the least amount of microcrack.