Hesarkhani Azadeh, Fotovat Farnoush, Saneian Fatemeh, Akbari Hosein, Allahbakhshi Hanif
Department of Endodontics, Faculty of Dentistry, Kashan University of Medical Sciences, Kashan, Iran.
Department of Prosthodontics, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
Front Dent. 2021 Oct 17;18:37. doi: 10.18502/fid.v18i37.7562. eCollection 2021.
This study aimed to compare the retention of cast posts cemented with four types of cements and assess the mode of root fracture following their removal. In this in vitro, experimental study, 48 upper central incisors were randomly divided into 4 groups of 12, and were endodontically treated. The fabricated cast posts in each group were cemented with zinc phosphate (Masterdent), glass ionomer (GI; Meron), Meta resin cement, and Panavia SA resin cement. A device was customized for post removal by a universal testing machine similar to WAM X pliers. The retention of cemented posts was measured by the pull-out test in a universal testing machine. Next, the teeth were macroscopically and microscopically inspected regarding the occurrence and sites of catastrophic fracture, cracks, or craze lines. Quantitative and qualitative data were analyzed by ANOVA, and Chi-square test, respectively (P<0.05). ANOVA showed a significant difference in the mean retention of cements (P<0.001). Panavia provided the highest retention (278.6±34.9 N) followed by zinc phosphate (221.9±28.88 N), GI (161.3±60.7 N), and Meta (140.4±66.54 N). There was no significant difference between the groups regarding the pattern of root fracture (P=0.39). However, site and extent of fractures were significantly different among the groups (P<0.05). The conventional cements provided optimal retention and caused less root damage after post removal. Thus, cements providing adequate retention and allowing easier post removal are recommended for use in endodontically treated teeth with a possibility of requiring retreatment.
本研究旨在比较用四种不同类型的粘结剂粘结的铸造桩的固位力，并评估其拆除后的牙根折断模式。在这项体外实验研究中，48颗上颌中切牙被随机分为4组，每组12颗，并进行了根管治疗。每组制作的铸造桩分别用磷酸锌（Masterdent）、玻璃离子水门汀（GI；Meron）、Meta树脂粘结剂和Panavia SA树脂粘结剂进行粘结。定制了一种类似于WAM X钳的装置，用于通过万能试验机拆除桩。通过在万能试验机上进行拔出试验来测量粘结桩的固位力。接下来，对牙齿进行宏观和微观检查，观察灾难性折断、裂纹或龟裂线的发生情况和部位。分别采用方差分析和卡方检验对定量和定性数据进行分析（P<0.05）。方差分析显示粘结剂的平均固位力存在显著差异（P<0.001）。Panavia提供的固位力最高（278.6±34.9 N），其次是磷酸锌（221.9±28.88 N）、GI（161.3±60.7 N）和Meta（140.4±66.54 N）。各组之间在牙根折断模式方面没有显著差异（P=0.39）。然而，各组之间骨折的部位和范围存在显著差异（P<0.05）。传统粘结剂提供了最佳的固位力，并且在拆除桩后对牙根造成的损伤较小。因此，对于可能需要再次治疗的根管治疗后的牙齿，建议使用具有足够固位力且便于拆除桩的粘结剂。
