机用ProTaper根管预备附加不同超声冲洗液对根管显微硬度的影响

Influence of different ultrasonic irrigation solutions after root canal preparation with ProTaper by machine on micro-hardness of root canal dentin

目的 :探讨机用镍钛ProTaper根管预备附加不同超声冲洗液对根管壁牙本质显微硬度的影响。方法 :收集60颗离体单根管上颌前牙,随机分为6组,A组为对照组,B组应用机用镍钛ProTaper根管预备至F3,C组预备后附加3%过氧化氢溶液超声冲洗1 min,D组预备后附加口泰漱口液超声冲洗1 min,E组预备后附加17%EDTA溶液超声冲洗1 min,F组预备后附加蒸馏水超声冲洗1 min。将每个牙根平均横截为根上、根中和根尖3段,再纵向劈开,用显微硬度仪分别测量各组根管壁显微硬度。采用SPSS 17.0软件包对数据进行统计学分析。结果:A组根管各处的显微硬度分别为(52.66±1.64)HV、(52.08±1.53)HV和(51.47±2.53)HV,差异无显著性(P>0.05),其他各组的根尖1/3显微硬度均低于根颈和根中1/3,差异显著(P<0.05)。在根颈1/3和根中1/3,E组显微硬度分别为(44.65±1.33)HV和(42.55±1.12)HV,与其他各组相比,差异显著(P<0.05)。在根尖1/3,E组显微硬度为(37.82±1.60)HV,下降最为显著,其次为C组,显微硬度为(44.14±1.73)HV。B组、D和F组之间相比,无显著性差异(P>0.05)。结论:机用镍钛ProTaper根管预备至F3可使根尖1/3显微硬度下降。17%EDTA溶液超声冲洗1 min可使根管各部显微硬度下降,3%过氧化氢可使根尖1/3显微硬度下降,口泰漱口液和蒸馏水对根管各部牙本质显微硬度值无明显影响。

PURPOSE： To develope the influence of different ultrasonic irrigations after root canal preparation with nickel titanium ProTaper on micro-hardness of root canal dentin. METHODS： Sixty of maxillary anterior teeth with single-canal were collected and randomly divided into 6 groups. Group A was control group, group B was prepared to F3 with nickel titanium ProTaper by machine, group C was ultrasonic irrigated with 3% hydrogen peroxide solution for 1 minute after preparation, group D was ultrasonic irrigated with koutai mouthwash for 1 minute after preparation, group E was ultrasonic irrigated with 17% EDTA solution for 1 minute after preparation, group F was ultrasonic irrigated with distilled water for 1minute after preparation. The roots were then sectioned horizontally into 3 parts,split longitudinally into halves and examined under a micro Vickers hardness test machine. The data was analyzed by one-way ANOVA and t test with SPSS17.0 software package. RESULTS： The micro-hardness of group A was（52.66±1.64） HV,（52.08±1.53）HV and（51.47±2.53）HV. There was no significant difference in all parts of the root canal in group A（P〉0.05）. The micro-hardness of the apical third of root canal was lower than that of the cervical and middle of root canal in the other groups（ P〈0.05）. In the cervical and middle third of the root canals, the micro-hardness of group E was（44.65 ±1.33） HV and（42.55±1.12） HV, and there were statistical significances between group E and the other groups（P 〈0.05）.In the apical third of root canal,the micro-hardness of group E was（37.82±1.60）HV, and group C was（44.14±1.73） HV, both of the comparative differences with other groups were statistically significant（P〈0.05）. There was no significant difference among group B, group D and group F（P〉0.05）. CONCLUSIONS： Root canal preparation to F3 with nickel titanium ProTaper by machine can make the micro-hardness of the apical third of root canal decrease. Ultrasonic irrigation with 17% EDTA solution for 1 minute can make the micro-hardness of the root canal decrease ultrasonic irrigation with. Ultrasonic irrigation with 3% hydrogen peroxide can make the micro-hardness of the apical third of root canal decrease. Ultrasonic irrigation with Koutai mouthwash and distilled water for 1 minute have no influence on the micro-hardness of root canal.