不同桩道预备时机对三种根尖封闭剂封闭效果的影响

目的 研究经3种根尖封闭剂充填后不同桩道预备时机对根管治疗术后根尖区微渗漏的影响.方法 将60颗单根管离体牙,经逐步后退法预备根管,采用简单随机分组的方法分为A、B、C3组,每组20颗,每组采用不同的根管封闭材料,用相同的牙胶尖冷侧方加压技术进行根管充填,对3组标本分别进行即刻和延迟1周桩道预备,每组抽取2颗牙为阴性对照不进行桩道预备,观察根尖部染料微渗漏情况.结果 即刻预备条件下A组和B组较C组具有较好的根尖封闭作用,微渗漏值差异无统计学意义(P＞0.05)；延迟预备组中B组产生的微渗漏较其他两组高(2.03±0.33) mm,差异具有统计学意义(P＜0.05).C组即刻预备条件下比延迟预备产生较大微渗漏但差异无统计学意义,其余两组延迟预备产生的微渗漏明显大于即刻预备组(P＜0.05).结论 即刻桩道预备能保护根尖封闭效果,选择具有粘接性能的根管封闭剂封闭效果较好.

Effect of immediate and delayed post space preparation on the apical seal of root canals filling with two kinds of root canal sealants

Objective To investigate the effect of immediate and delayed post space preparation on the integrity of the apical seal.Methods Seventy extracted human single-rooted human teeth were biomechanically prepared using the step-back technique.They were randomly assigned to 2 experimental groups of 35 teeth each and filled with two root canal sealants (AHplus and Cortisomol) separately.Thirty teeth in each group were prepared and the other five served as negative controls.Apical microleakage was evaluated with ink dye penetration.Results Cortisomol group showed better apical sealing effect than did other groups when teeth were prepared immediatlly,and microleakage values showed no statistically significant difference ( P ＞ 0.05 ),Vitapex group generated more microleakage than did the other Two groups with delayed preparation ( 2.03 ± 0.33 mm),the difference was statistically significant ( P ＜ 0.05 ).Cortisomol group had a greater microleakage than other groups did when prepared immediately,but the difference was not statistically significant.The other two groups showed significantly greater microleakage with delayed preparation than they did with immediate preparation group ( P ＜ 0.05 ).Conclusions Immediate post space preparation creates less microleakage than delayed preparation does.