The effect of drilling parameters on bone

✍ Scribed by H. Ohashi; M. Therin; A. Meunier; P. Christel

• Publisher: Springer
• Year: 1994
• Tongue: English
• Weight: 462 KB
• Volume: 5
• Category: Article
• ISSN: 0957-4530
• DOI: 10.1007/bf00121095

✦ Synopsis

For biocompatibility testing, cylindrical specimens are often inserted into drilled cortical defects. However, little attention has been paid to the drilling conditions. Our previous experience revealed that bone formation in drilled cortial defects was delayed by 5000 r.p.m. drilling due to thermal necrosis around the hole compared with 500 r.p.m., and the use of irrigation was effective in reducing the degree of local ischaemia. Therefore, this experiment was performed to investigate the short-and long-term effects of the drilling conditions on bone response to cylindrical porous hydroxyapatite implants. Two holes were drilled in rabbit tibia diaphysis with two different drilling conditions: 500 r.p.m, with irrigation and 5000 r.p.m. without irrigation. Rabbits were killed at 2 or 12 weeks post-operatively. The bone formation on the hole edge, on the implant surface and within the implant pores was investigated. At 2 weeks post-operatively the area of newly formed bone within the implant pores at 500 r.p.m. was significantly greater, whereas there was no difference at 12 weeks. These results indicate that the drilling conditions affect the short-term bone response to the implants. Therefore, the drilling conditions must be taken into consideration when investigating the early bone response to materials implanted into drilled cortical defects.