Haralur Satheesh B, Al Faifi Ali Hassan, Al-Qahtani Saed Saleh
Department of Prosthodontics, College of Dentistry, King Khalid University, Abha, Kingdom of Saudi Arabia.
Department of Periodontology, College of Dentistry, King Khalid University, Abha, Kingdom of Saudi Arabia.
J Indian Prosthodont Soc. 2014 Jun;14(2):156-60. doi: 10.1007/s13191-013-0296-0. Epub 2013 Jun 19.
To evaluate the influence of complete smear layer removal by EDTA on the resistance of root fracture of tooth restored with fiber post. Twenty single rooted premolars with average root length 16 ± 1 mm were randomly divided into two groups of ten each. All teeth were obturated with guttapercha after root canal preparation, sectioned 4 mm above the cement-enamel junction. In group I, teeth root canals were etched with 37 % phosphoric acid, fiber post cemented with self adhesive resin cement. In group II, teeth radicular dentin was treated with 17 % EDTA, followed by fiber post cementation with dual cure resin cement. Coronal part of the teeth reestablished with posterior composite and NiCr full veneer coping along with 2 mm circumferential ferrule. Restored teeth were loaded with incremental force at 30° to the long axis of the root until fracture occurred. The data obtained was evaluated with paired sample T test to compare the fracture resistance between the test groups. Group I had the mean failure load of 1,883.70 N while group II had 1,622.80 N mean failure load. Paired sample T test showed statistically significant (p value = 0.033) failure load difference between the groups tested. Within the limits of this study, it may be concluded that: the complete removal of smear layer by EDTA found to have reduced the fracture strength of tooth roots restored with an epoxy fiber post.
为评估乙二胺四乙酸（EDTA）完全去除玷污层对纤维桩修复牙齿牙根抗折性的影响。选取20颗平均根长为16±1mm的单根前磨牙，随机分为两组，每组10颗。所有牙齿根管预备后用牙胶尖充填，在牙骨质-釉质界上方4mm处截断。在第一组中，牙齿根管用37%磷酸酸蚀，用自粘结树脂水门汀粘结纤维桩。在第二组中，牙齿根管牙本质用17% EDTA处理，随后用双固化树脂水门汀粘结纤维桩。牙齿冠部用后牙复合树脂和镍铬全冠修复，并带有2mm的环形箍。修复后的牙齿沿牙根长轴成30°角施加递增力直至发生折断。用配对样本T检验对所得数据进行评估，以比较试验组之间的抗折性。第一组的平均破坏载荷为1883.70N，而第二组的平均破坏载荷为1622.80N。配对样本T检验显示，试验组之间的破坏载荷差异具有统计学意义（p值=0.033）。在本研究的范围内，可以得出结论：乙二胺四乙酸（EDTA）完全去除玷污层会降低用环氧纤维桩修复的牙齿牙根的抗折强度。
