Rajput Akhil, Ataide Ida, Lambor Rajan, Monteiro Jeanne, Tar Malika, Wadhawan Neeraj
Department of Conservative Dentistry and Endodontics, Goa Dental College and Hospital, Bambolim, Goa, India.
Eur J Esthet Dent. 2010 Winter;5(4):398-411.
Reattachment of the fractured fragment of a traumatized tooth (whenever available and usable) has become the treatment of choice in cases of uncomplicated crown fractures. Despite the presence of various bonding materials and techniques, laboratory data evaluating the biomechanical aspects of such procedures is largely lacking in the literature. The objective of this in vitro study was to evaluate the fracture strength recovery of incisors, following fragment restoration with three different techniques. A total of 90 extracted human maxillary central incisors were subjected to crown fractured under standard conditions. This was carried out by applying a compressive force from the buccal aspect of the clinical crown using a universal strength testing machine. The fractured teeth were equality distributed in three groups, defined on the basis of the technique used for reattachment: i) overcontour, ii) internal dentinal groove and iii) direct buildup. Each group was further subdivided into three subgroups on the basis of the intermediate restorative material used for reattachment, namely: i) hybrid composite (Filtek Z100 Universal Restorative, ii) nanocomposite (Filtek Z350) and iii) Ormocer (Voco Admira). Following reattachment, the crowns were re-fractured under standard conditions. The force required for fracture was recorded and was expressed as a percentage of the fracture strength of the intact tooth. The data was expressed as a percentage of the fracture strength of the intact tooth. The data was analyzed using two-way ANOVA and Bonferroni tests for pair-wise comparison. The results showed no statistically significant differences in fractures strength between the three groups (P > 0.05). However, comparison of the subgroups revealed statistically significant higher strength recovery percentages for the hybrid and the nanocomposite compared with the Ormocer material (P < 0.05). It was concluded that material properties have a significant influence on the success of reattachment procedures.
对于外伤牙折断碎片的再附着（只要可行且可用），已成为单纯冠折病例的首选治疗方法。尽管存在各种粘结材料和技术，但文献中很大程度上缺乏评估此类操作生物力学方面的实验室数据。本体外研究的目的是评估采用三种不同技术进行碎片修复后切牙的抗折强度恢复情况。总共90颗拔除的人类上颌中切牙在标准条件下进行冠折。这是通过使用万能强度试验机从临床冠的颊侧施加压缩力来实现的。折断的牙齿平均分为三组，根据再附着所使用的技术定义为：i）超外形修复，ii）牙本质内沟修复，iii）直接堆塑修复。每组根据用于再附着的中间修复材料进一步细分为三个亚组，即：i）混合复合树脂（Filtek Z100通用修复树脂），ii）纳米复合树脂（Filtek Z350），iii）有机陶瓷（Voco Admira）。再附着后，在标准条件下对牙冠再次进行折断。记录折断所需的力，并表示为完整牙齿抗折强度的百分比。数据表示为完整牙齿抗折强度的百分比。使用双向方差分析和Bonferroni检验进行成对比较来分析数据。结果显示三组之间的抗折强度无统计学显著差异（P>0.05）。然而，亚组比较显示，与有机陶瓷材料相比，混合复合树脂和纳米复合树脂的强度恢复百分比在统计学上显著更高（P<0.05）。得出的结论是，材料性能对再附着操作的成功有显著影响。
