Department of Endodontics, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil.
Department of Dentistry II, Federal University of Maranhão, São Luís, Maranhão, Brazil.
Int Endod J. 2021 Sep;54(9):1653-1658. doi: 10.1111/iej.13549. Epub 2021 Jun 10.
To compare the bond strength of an epoxy resin-based sealer and two calcium silicate-based sealers (CSS) to gutta-percha discs using a new method.
Round discs of gutta-percha (n = 60), measuring 10 mm in diameter and 2 mm in thickness, were placed on a glass plate and a drop of each sealer (AH Plus, EndoSequence BC Sealer and EndoSeal MTA) was placed on their surface. Another identical disc was placed onto the first one and a standardized weight (0.0981 N) applied over them using a specially developed apparatus. Ten samples prepared for each sealer were submitted to a microshear bond strength test accomplished by a specially designed set-up coupled to a universal testing machine. The Kruskal-Wallis test followed by a post hoc procedure was used to compare groups considering the preliminary analysis of the raw data had indicated the nonadherence to a Gaussian distribution (Shapiro-Wilk, p < .05). Alpha error was set at 5%.
Overall, no premature failure occurred. All sealers had some degree of adhesiveness to gutta-percha discs but with a significant difference amongst them (Kruskal-Wallis, p = .019). The epoxy resin-based sealer (AH Plus) had significantly higher median shear bond strength values (1.43 MPa; 1.40-1.83) compared to EndoSeal MTA (0.53 MPa; 0.46-0.73) (p = .021) and EndoSequence BC Sealer (0.45 MPa; 0.34-0.46) (p = .023), whilst the lowest median value was observed with EndoSequence BC Sealer (0.45 MPa; 0.34-0.46) (p < .05).
CSS sealers had weaker bonding to gutta-percha when compared to the epoxy resin-based AH Plus sealer. The proposed methodology is an innovative and reproducible method for testing the bond strength of root canal sealers to gutta-percha.
采用一种新方法比较一种环氧树脂基密封剂和两种硅酸钙基密封剂（CSS）与牙胶尖的粘结强度。
将 60 个直径为 10mm、厚度为 2mm 的牙胶尖圆片放置在玻璃片上，在其表面各放置一滴（AH Plus、EndoSequence BC 密封剂和 EndoSeal MTA）。将另一个相同的牙胶尖圆片放在第一个牙胶尖圆片上，并用专门开发的装置在其上施加标准化重量（0.0981N）。为每种密封剂制备了 10 个样本，通过专门设计的装置与万能试验机耦合完成微剪切粘结强度测试。在对原始数据进行初步分析后，发现不符合正态分布（Shapiro-Wilk，p<.05），采用 Kruskal-Wallis 检验，然后进行事后检验，比较各组数据。误差α设为 5%。
总体而言，没有发生过早失效。所有密封剂都与牙胶尖有一定程度的粘附性，但彼此之间存在显著差异（Kruskal-Wallis，p=.019）。与 EndoSeal MTA（0.53MPa；0.46-0.73）（p=.021）和 EndoSequence BC 密封剂（0.45MPa；0.34-0.46）（p=.023）相比，基于环氧树脂的密封剂（AH Plus）具有显著更高的中位剪切粘结强度值（1.43MPa；1.40-1.83），而 EndoSequence BC 密封剂的中位值最低（0.45MPa；0.34-0.46）（p<.05）。
与基于环氧树脂的 AH Plus 密封剂相比，CSS 密封剂与牙胶尖的粘结强度较弱。所提出的方法是一种创新且可重复的根管密封剂与牙胶粘结强度测试方法。
