Ramazanzadeh Barat Ali, Fatemi Kazem, Dehghani Mahboobe, Mohtasham Nooshin, Jahanbin Arezoo, Sadeghian Hamed
Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
Oral & Maxillofacial Diseases Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
ISRN Dent. 2014 Apr 6;2014:179037. doi: 10.1155/2014/179037. eCollection 2014.
Objectives. This study aimed to evaluate the effect of immediate and delayed loading of orthodontic micro-implants on bone-implant contact. Materials and Methods. Sixty four micro-implants were implanted in dog's jaw bone. The micro-implants were divided into loaded and unloaded (control) groups. The control group had two subgroups: four and eight weeks being implanted. The loaded group had two subgroups of immediate loading and delayed (after four weeks healing) loading. Loaded samples were subjected to 200g load for four weeks. After sacrificing the animals micro-implants and surrounding tissues were observed histologically. Bone-implant contact ratios (BIC) were calculated and different groups' results were compared by three-way ANOVA. Results. Mean survival rate was 96.7% in general. Survival rates were 96.7%, 94.4% and 100% for control, immediate and delayed loaded groups, respectively. BIC values were not significantly different in loaded and control groups, immediate and delayed loading groups, and pressure and tension sides. Mandibular micro-implants had significantly higher BIC than maxillary ones in immediate loading, 4-weeks control, and 8-weeks control groups (P = 0.021, P = 0.009, P = 0.003, resp.). Conclusion Immediate or delayed loading of micro-implants in dog did not cause significant difference in Bone-implant contact which could be concluded that healing time had not significant effect on micro-implant stability.
目的。本研究旨在评估正畸微种植体即刻加载和延迟加载对骨-种植体接触的影响。材料与方法。在犬颌骨中植入64枚微种植体。将微种植体分为加载组和未加载组（对照组）。对照组有两个亚组：植入后4周和8周。加载组有即刻加载和延迟加载（愈合4周后）两个亚组。加载样本施加200g负荷，持续4周。处死动物后，对微种植体及周围组织进行组织学观察。计算骨-种植体接触率（BIC），并通过三因素方差分析比较不同组的结果。结果。总体平均存活率为96.7%。对照组、即刻加载组和延迟加载组的存活率分别为96.7%、94.4%和100%。加载组和对照组、即刻加载组和延迟加载组以及压力侧和张力侧的BIC值无显著差异。在即刻加载组、4周对照组和8周对照组中，下颌微种植体的BIC显著高于上颌微种植体（分别为P = 0.021、P = 0.009、P = 0.003）。结论犬微种植体的即刻或延迟加载在骨-种植体接触方面未引起显著差异，由此可以得出愈合时间对微种植体稳定性无显著影响。
