诺丽对冠部牙本质粘接强度及纳米渗漏的影响

Effect of Morinda citrifolia juice on the bonding strength and nanoleakage of crowns dentin

目的探讨诺丽(Morinda citrifolia juice,MCJ)联合乙二胺四乙酸盐(ethylene diaminete traacetic acid,EDTA)根管冲洗对冠部牙本质粘接强度及纳米渗漏的影响,并与临床上最常用的根管冲洗液次氯酸钠(sodi⁃um hypochlorite,NaClO)相比较,为临床应用提供参考。方法本研究已通过单位伦理审查委员会批准。选取63颗因正畸拔除的人前磨牙,去除表面釉质暴露牙本质平面后,根据冲洗液不同随机分为对照组(蒸馏水组)和6个实验组,即:A组2.5%NaClO、B组5.25%NaClO、C组6%MCJ、D组2.5%NaClO⁃17%EDTA、E组5.25%NaClO⁃17%EDTA和F组6%MCJ⁃17%EDTA(n=9),分别用相应冲洗液浸泡20 min后,在其表面分层堆积4 mm×4 mm×3 mm的Z350树脂块,每组选取6个样本,低速切割机将每个样本切割成1 mm×1 mm×8 mm的试件条,进行微拉伸粘接强度测试,随后在体视显微镜下观察断裂类型;每组剩余的3个样本经老化后切割成1 mm厚的薄片,进行界面纳米渗漏测试以及扫描电子显微镜下观察树脂⁃牙本质粘接界面。结果各组微拉伸粘接强度测试值均有显著性差异(P<0.05),对照组粘接强度最高。实验组中,B组粘接强度最低,以粘接界面破坏为主;F组粘接强度最高,以混合破坏为主。各组纳米渗漏值均有显著性差异(P<0.05),对照组纳米渗漏值最低。实验组中,B组纳米渗漏值最高、树脂突较细,F组纳米渗漏值最低、树脂突粗大且密集。结论NaClO浓度越高,冠部牙本质的粘接强度及边缘封闭性越差;MCJ联合EDTA根管冲洗对冠部牙本质的粘接强度和边缘封闭性的影响小于NaClO联合EDTA根管冲洗。

Objective To explore the effect of Morinda citrifolia juice(MCJ)combined with ethylene diamine tet⁃raacetic acid(EDTA)on premolar bonding strength and nanoleakage and compare the results with those of the most commonly used root canal irrigation solution,sodium hypochlorite(NaClO),to provide a reference for clinical applica⁃tion.Methods This study was approved by the ethics review committee.Sixty⁃three human premolars extracted for orthodontic treatment were randomly divided into a control group(distilled water group)and 6 experimental groups ac⁃cording to the different rinsing solutions used after the surface enamel was removed.The experimental groups included Group A(2.5%NaClO),Group B(5.25%NaClO),Group C(6%MCJ),Group D(2.5%NaClO⁃17%EDTA),Group E(5.25%NaClO⁃17%EDTA),and Group F(6%MCJ⁃17%EDTA)(n=9).After soaking in the corresponding rinsing so⁃lution for 20 minutes,they were layered and stacked on their surfaces to form 4 mm×4 mm×3 mm Z350 resin blocks.Six samples from each group were cut into 1 mm×1 mm×8 mm specimen strips for microtensile bonding strength test⁃ing.The fracture type was determined under a stereomicroscope,and the remaining 3 samples from each group were aged and cut into 1 mm thick slices for interface nanoleakage testing and scanning electron microscopy observation of the resin dentin bonding interface.Results There were significant differences in the microtensile bonding strength among the groups(P<0.05),and the control group had the highest bonding strength.Among experimental groups,Group B had the lowest bonding strength,mainly bonding interface fracture,and Group F had the highest bonding strength,mainly mixed fracture.There were significant differences in nanoleakage among all groups(P<0.05),and the control group had the lowest nanoleakage value.Among experimental groups,Group B had the highest nanoleakage,with resin protrusions being unaltered,and Group F had the lowest nanoleakage value,with resin protrusions being thick and dense.Conclusion The higher the concentration of NaClO was,the worse the bonding strength and edge sealing of the crown dentin were.The effects of root canal irrigation with MCJ and EDTA on the adhesive strength and edge sealing of crown dentin were less pronounced than those of root canal irrigation with NaClO and EDTA.