Division of Pediatric and Preventive Dentistry, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India.
Dent Traumatol. 2024 Feb;40(1):5-10. doi: 10.1111/edt.12888. Epub 2023 Sep 20.
BACKGROUND/AIMS: The recommended treatment for uncomplicated crown fractures is bonding the fractured fragment or the fragment reattachment. A paucity was identified regarding the studies comparing the efficacy of micro-hybrid and nanohybrid composites in fragment reattachment. Hence, the present study aimed to evaluate and compare three materials for bonding of fragments rehydrated by humidification in teeth with uncomplicated crown fractures.
Eighty mandibular bovine incisors with similar dimensions and free of any structural deformities were fractured similar to the technique followed in previous studies. Fracture was simulated, fragments, and stumps were coded, stumps were stored in artificial saliva and the fragments were dehydrated at room temperature and pressure. They were randomly assigned to Group-1 (no rehydration), Group-2 (rehydrated and bonded by flowable nanohybrid composite-3M Filtek Supreme Syringe Flowable Composite Resin-A2, Sao Paulo, Brazil), Group-3 (rehydrated and bonded by flowable micro-hybrid composite- Ruby Flow, InciDental, England, United Kingdom), and Group-4 (rehydrated and bonded by light-cured Glass-Ionomer-Cement-Voco Ionoseal, Cuxhaven, Germany). The samples were subjected to a universal testing machine to evaluate the force required to fracture the bonded fragments.
The highest median value of the force required to fracture was recorded for Group 2 (208.4 N) followed by Group 3 (195.2). The force required to fracture the bonded fragments was lowest in Group 4 (67.2 N) which was lower than the negative control (131.4 N). The differences between the observations in Groups 2 and 3 were not found to be statistically significant.
The nano and micro-hybrid composites showed greater force required to fracture than fragments bonded by LC-GIC. Dehydrated fragments bonded using nanocomposites performed better than rehydrated fragments bonded by using LC-GIC.
背景/目的：对于简单冠折，推荐使用粘结剂粘结折裂片或复位折裂片。关于比较微混合和纳米混合复合材料在折裂片复位方面疗效的研究相对较少。因此，本研究旨在评估和比较三种材料用于粘结经加湿再水化的简单冠折牙折裂片。
80 颗下颌牛切牙具有相似的尺寸且无任何结构畸形，采用类似先前研究中使用的技术进行折断。模拟折断后，对裂片和残端进行编码，残端保存在人工唾液中，裂片在室温及大气压下脱水。将裂片随机分为 4 组：第 1 组（不水化）、第 2 组（水化后用可流动纳米混合复合材料 3M Filtek Supreme 注射器流动复合树脂 A2 粘结，巴西圣保罗）、第 3 组（水化后用可流动微混合复合材料 Ruby Flow 粘结，英国英西德牙科公司）和第 4 组（水化后用光固化玻璃离子水门汀粘结，德国库克斯港）。将样本置于万能试验机上，以评估折断粘结裂片所需的力。
记录到的折断粘结裂片所需的最大中位数力值见于第 2 组（208.4N），其次是第 3 组（195.2N）。第 4 组（67.2N）的折断粘结裂片所需力最低，低于阴性对照组（131.4N）。第 2 组和第 3 组之间的观察结果差异无统计学意义。
纳米和微混合复合材料比用 LC-GIC 粘结的折裂片所需的力更大。用纳米复合材料粘结的脱水裂片比用 LC-GIC 粘结的水化折裂片表现更好。
