BACKGROUND:Drilling is a well-known mechanical operation performed for fixing fracture at required locations in bone. The process may produce mechanical and thermal alterations in the structure of the bone and surrounding tissues leading to irreversible damage known as osteonecrosis. OBJECTIVE:Themain purpose of this study was to measure the level of biological damage in bone when a drill assisted by low and high levels of vibrations is penetrated into bone tissue. METHODS:Histopathology examination of sections of bones has been performed after drilling the bone using a range of vibrational frequency and rotational speed imposed on the drill with and without supply of saline for cooling. RESULTS:Cell damage in bone was caused by the combined effect of drill speed and frequency of vibrations. Histopathology examination revealed more damage to bone cells when a frequency higher than 20 kHz was used in the absence of cooling. Cooling the drilling region helped minimize cell damage more at a shallow depth of drilling compared to deep drilling in the cortex of cortical bone. The contribution of cooling in minimizing cell damage was higher with a lower drill speed and frequency compared to a higher drill speed and frequency. CONCLUSION:Vibrational drilling using a lower drill speed and frequency below 25 kHz in the presence of cooling was found to be favorable for safe and efficient drilling in bone.

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振动钻孔对骨骼生物损伤的实验研究

背景：钻孔是一种众所周知的机械操作，用于在骨骼中的所需位置固定骨折。该过程可能会在骨骼和周围组织的结构中产生机械和热变化，从而导致称为骨坏死的不可逆损伤。目的：本研究的主要目的是测量在低振动和高振动辅助下钻入骨组织时骨中生物损伤的程度。方法：在使用一定范围的振动频率和旋转速度对骨进行钻孔后，对骨切片进行组织病理学检查，无论是否提供盐水冷却。结果：骨细胞损伤是由钻速和振动频率共同作用引起的。组织病理学检查显示，在没有冷却的情况下使用高于 20 kHz 的频率时，对骨细胞的损伤更大。与在皮质骨皮质中的深钻孔相比，冷却钻孔区域有助于在浅钻孔深度下更大程度地减少细胞损伤。与较高的钻孔速度和频率相比，较低的钻孔速度和频率对最小化细胞损伤的冷却贡献更大。结论：在存在冷却的情况下，使用较低的钻孔速度和频率低于 25 kHz 的振动钻孔被发现有利于在骨骼中安全有效地钻孔。与较高的钻孔速度和频率相比，较低的钻孔速度和频率对最小化细胞损伤的冷却贡献更大。结论：在存在冷却的情况下，使用较低的钻孔速度和频率低于 25 kHz 的振动钻孔被发现有利于在骨骼中安全有效地钻孔。与较高的钻孔速度和频率相比，较低的钻孔速度和频率对最小化细胞损伤的冷却贡献更大。结论：在存在冷却的情况下，使用较低的钻孔速度和频率低于 25 kHz 的振动钻孔被发现有利于在骨骼中安全有效地钻孔。