Effect of Rotational Speed of Drill Bit on Surface Defects with H&E Stain in Bone Drilling (An Animal Study)

Drilling of bone is used to fix the fractures with screws, wires or plates. The interaction between hole surface surface and fracture stabilization components is effective in the bonding strength of the stabilization process. During bone drilling, the temperature could increase above 47 °C and cause irreversible thermal necrosis. The surface roughness can be considered as a sign of damage of the bone cells.
This study looks at the effect of rotational speed of drilling of bone on production of surface defects to determine the best processing condition for minimizing the osteonecrosis and surface defects. Seven different rotational speeds in drilling beef femur were used-in non-cooling and liquid cooling phases. In all tests the temperature was measured. After cutting samples, using hematoxylin-eosin staining were stained for detection of surface defects.
The lowest heat prodution was with use of liquid cooling. The drill speed of 1500 rpm with liquid cooling showed the maximum temperature of 48.5°C without production of surface debris and defects as witnessed in stained bone segment.
Cooling application in bone drilling process avoids over and thus less thermal necrosis, which gives the lowest number of surface defects and highest quality wall surface hole.