J Adhes Dent. 2019;21(1):37-46. doi: 10.3290/j.jad.a41871.
To evaluate the method of resin cement mixing and insertion into the root canal on resin cement porosity and fiberglass-post push-out bond strength (PBS).
One hundred twenty human single-rooted teeth were sectioned to a length of 15 mm, en-do-dontically filled, and received a fiberglass post cemented with 3 self-adhesive resin cements (RelyX U200, seT, Panavia SA) using 4 mixing methods/insertion techniques (handmix/endodontic file, handmix/Centrix syringe, automix/conventional tip, automix/endo tip). The samples were scanned using micro-CT. Two slices from the cervical, middle, and apical thirds were submitted to push-out bond strength (PBS) testing, and failure modes were classified. The PBS, volume of resin cement, and porosity data were analyzed using ANOVA and Tukey's test.
The porosity was lowest in the cervical third and highest in the apical third, irrespective of the resin cement. The porosity was lower in the the automix/endo tip group compared to the handmix/endodontic file group. The use of Centrix or endo tip reduced the porosity and increased the PBS in the apical third compared with the use of endodontic files. The root canal depth reduced the PBS for U200 and seT when handmix/endodontic files were used. U200 and seT using the automix method increased the PBS, thus eliminating the effect of root region, irrespective of the insertion technique. In general, U200 showed higher PBS and Panavia lower PBS. Adhesive failure between root dentin and resin cement was predominant.
Automixing the cement and using an endo tip produces fewer voids and increased the bond strengths.
评估根管内树脂水泥混合和插入方法对树脂水泥孔隙率和纤维玻璃桩推出粘结强度（PBS）的影响。
将 120 个人类单根牙切成 15mm 长，根管内填充，并用 3 种自粘树脂水泥（RelyX U200、seT、Panavia SA）用 4 种混合方法/插入技术（手混/根管锉、手混/Centrix 注射器、自动混合/常规尖端、自动混合/根管尖端）粘结纤维玻璃桩。使用微 CT 扫描样本。从颈、中、根尖三分之一处取两个切片进行推出粘结强度（PBS）测试，并对失效模式进行分类。使用 ANOVA 和 Tukey 检验分析 PBS、树脂水泥体积和孔隙率数据。
无论使用哪种树脂水泥，根尖三分之一的孔隙率最低，颈三分之一的孔隙率最高。与手混/根管锉组相比，自动混合/根管尖端组的孔隙率较低。与使用根管锉相比，使用 Centrix 或根管尖端可减少根尖三分之一的孔隙率并增加 PBS。根管深度降低了 U200 和 seT 在手混/根管锉时的 PBS。使用自动混合方法时，U200 和 seT 增加了 PBS，从而消除了根区的影响，无论插入技术如何。一般来说，U200 显示出更高的 PBS 和 Panavia 更低的 PBS。树脂水泥与牙根牙本质之间的黏附性失效是主要的失效模式。
混合水泥并使用根管尖端可减少孔隙率并提高粘结强度。
