Does MTA affect fiber post retention in repaired cervical root canal perforations?

Abstract This study evaluated the effect of mineral trioxide aggregate (MTA) on the retention of fiber posts in repaired root canal perforations. Ten-millimeter post spaces were prepared in 60 endodontically treated bovine incisors. Root perforations were created in half of the root canals in the cervical area prior to being filled with white MTA-Angelus. Fiber posts were luted into the root canals with two self-adhesive (RelyX Unicem or Set) or self-etching (Panavia F) resin cements. The posts were submitted to a pull-out test, and the data were submitted to two-way ANOVA and Tukey’s post hoc tests (α = 0.05). The fiber posts exhibited reduced retention in MTA-repaired root canal perforations, regardless of the type of resin cement that was used (p < 0.001). Self-adhesive resin cements provided higher bond strength values than Panavia F, while no difference was observed between RelyX Unicem and Set (p > 0.05). The presence of MTA in repaired root perforations negatively affected post retention. In addition, self-adhesive cements seemed to be the best option to lute fiber posts within a root canal in these cases.摘要 本研究评估了矿物三氧化物凝聚体（mineral trioxide aggregate, MTA）对修复后根管穿孔内纤维桩固位效果的影响。研究选取60颗经牙髓治疗的牛切牙，制备了10mm长度的桩道。于半数根管的颈区制作根管穿孔，随后使用白色MTA-Angelus进行充填修复。采用两种自粘接型（RelyX Unicem与Set）或自酸蚀型（Panavia F）树脂水门汀将纤维桩粘接固定于根管内。对纤维桩实施抗拔出试验，所得数据采用双因素方差分析与Tukey事后检验进行统计学分析（检验水准α=0.05）。结果显示，无论使用何种类型的树脂水门汀，纤维桩在经MTA修复的根管穿孔内的固位力均显著下降（p<0.001）。自粘接型树脂水门汀的粘接强度显著高于Panavia F，而RelyX Unicem与Set之间的粘接强度无统计学差异（p>0.05）。经MTA修复的根管穿孔会对桩体固位产生负面影响；此外，在该类病例中，自粘接型水门汀似乎是根管内粘接纤维桩的最优选择。