不同黏结材料对纤维桩修复牙根发育不完全牙抗折性能的影响

Effect of fiber posts on the fracture resistance of immature permanent teeth

目的:观察比较不同黏结材料对牙根发育不完全牙修复后抗折强度的差异,以期为临床使用桩核系统修复根尖诱导成形术后的牙提供依据。方法:收集符合纳入标准的因正畸需要拔除的第一、二前磨牙75颗,随机分为5组,实验组2组(纤维桩+黏结材料充填)、阳性对照组2组(黏结材料桩道充填)、阴性对照组1组(根管充填后不作处理),每组15颗牙,将桩核系统修复后的样本牙进行包埋,采用TY-8000型电子万能测试机分别测量牙根颈1/3和中1/3的抗折强度,比较不同黏结材料修复对牙根抗折强度的影响。采用SAS6.0软件包对数据进行分析。结果:实验1组牙根颈、中部的抗折强度分别为(999±75.40)N、(799±21.77)N,实验2组牙根颈、中部的抗折强度分别为(896±15.73)N、(739±20.14)N。经统计学分析,2组间根颈1/3和中1/3抗折强度差异有显著性(P<0.01);各实验组与阳性对照、阴性对照组之间差异均有显著性。结论:不同黏结材料对纤维桩修复后的牙根发育不完全的牙各部位的抗折强度有影响。在牙根发育不完全牙玻璃纤维桩的修复中,建议用复合树脂水门汀作为黏结材料。

PURPOSE： To investigate the influence of different cements on the fracture resistance of the immature teeth restored with fiber post and the fracture resistance at different parts of the roots. METHODS： Seventy-five untreated maxillary and mandibular premolar were selected for this study, and randomly assigned to 5 groups, including 2 experimental groups, 2 positive controls, and 1 negative control. After root canal therapy was applied for each tooth, the post space was prepared to standard size and restored according to the proposal. The samples were embedded, and the fracture resistance at cervical 1/3 and middle 1/3 of the root was measured. The data was analyzed with SAS6.0 software package. RESULTS： The average fracture resistance at cervical, middle 1/3 was （999±75.40）N,（799±21.77）N in samples restored with 1.9mm fiber post ＋ composite resin cement, （896±15.73）N, （739±20.14）N in samples restored with 1.9mm fiber post＋glass ionomer cement, the difference was significant（P〈0.01）. CONCLUSIONS： The cements play some role on the fracture resistance at cervical 1/3 and middle 1/3 of the root of immature teeth restored with fiber post. The immature teeth are at high risk of root fracture because of its thin dentin , therefore we propose to use composite resin cement as a bonding material when immature teeth are restored with fiber posts. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality （Grant No.08DZ2271100）.