Department of Stomatology - Periodontology, School of Dentistry, University of Santiago de Compostela, Santiago de Compostela, Spain.
Clin Oral Implants Res. 2011 Jan;22(1):92-9. doi: 10.1111/j.1600-0501.2010.02009.x. Epub 2010 Oct 6.
to evaluate early osseointegration of dental implants installed with two different drilling protocols.
thirty-six cylindrical shape Mozo Grau implants, with a diameter of 3.75 and 11 mm long, were placed into the distal condyle (submerged) of each femur of 18 New Zealand rabbits. In the control group, a 3.3 mm diameter drill was used as the last one prior implant installation (standard protocol). In the test group, the same procedure was carried out but an additional 3.5 mm drill was used as the final one (oversized protocol) Thus, we could obtain different primary stability at day 0 between groups. Sacrifice of the animals was after 2, 4 and 8 weeks. Histomorphometric analysis (bone-to-implant contact ratio [BIC%]) and implant stability quotient (ISQ) values (Ostell ) were registered at each sacrifice time.
the ISQ values were statistically significant different between groups at day 0 (control: 69.65; test: 64.81); and after 2 weeks (control: 77.93; test: 74). However, after 4 and 8 weeks the results were similar. BIC% showed a similar tendency, with 58.69% for the control group and 40.94% for the test group after 2 weeks, this difference being statistically significant. At 4- and 8-week interval, BIC% was similar.
at 2-week interval (early healing), osseointegration had been influenced by different primary stability at implant installation, being slower in the oversized protocol (lower primary stability), which could be especially risky in challenging clinical situations, such as soft bone (class 3 and 4) and early/immediate loading. However, from 4 week on, these differences disappeared. Nevertheless, we have to consider that a direct transfer of the results of this animal study (time bone repair mechanisms) into clinic has to be done with caution.
评估两种不同种植体植入方法对种植体早期骨整合的影响。
将 36 个 Mozo Grau 圆柱形种植体（直径 3.75mm，长 11mm）植入 18 只新西兰大白兔双侧股骨髁远端（植入方式为潜入式）。在对照组中，使用直径 3.3mm 的钻头作为最后一道种植体植入前的预备孔（标准方案）。在实验组中，采用相同的程序，但使用直径 3.5mm 的钻头作为最后一道预备孔（扩孔方案），从而使两组在种植体植入的即刻获得不同的初始稳定性。在 2、4 和 8 周时处死动物。在每个时间点，通过组织形态计量学分析（骨-种植体接触率[BIC%]）和种植体稳定性指数（ISQ 值[Ostell]）进行评估。
在第 0 天（对照组：69.65；实验组：64.81）和第 2 周（对照组：77.93；实验组：74.01），两组的 ISQ 值存在显著差异。然而，在第 4 周和第 8 周时，结果相似。BIC% 也呈现出相似的趋势，第 2 周时对照组为 58.69%，实验组为 40.94%，差异有统计学意义。在第 4 周和第 8 周时，BIC% 相似。
在第 2 周（早期愈合阶段），种植体植入时不同的初始稳定性会影响骨整合，扩孔方案（较低的初始稳定性）下的骨整合较慢，这在具有挑战性的临床情况下，如骨质疏松（3 类和 4 类）和早期/即刻负重，可能存在更高的风险。然而，从第 4 周开始，这些差异消失。尽管如此，我们必须谨慎地将该动物研究（骨修复机制时间）的结果直接应用于临床。
