Analytical and experimental investigation of influence of rotational speed and feed on temperature elevation in cortical bone drilling

Bone drilling process is one of the essential steps in orthopedic surgeries. If temperature of this process is more than 47 ° C, thermal necrosis occurs. In the event of the thermal necrosis, bone consolidation is not well done. For this reason, a lot of research has been done to reduce the thermal necrosis. In this study, by using an analytical model, bone temperature elevation during drilling was investigated at different feed rates and rotational speeds. To validate the analytical results, the bone temperature elevations were evaluated by comparison with bone drilling process using bovine femurs. With comparison the results, it was found that there are differences between analytical and experimental results that are related to incorrect estimation of the fraction of total heat generated that flows into the bone. Therefore, the correct values of this fraction were obtained after comparing analytical and experimental results. Finally, it was concluded that the fraction is dependent on the feed rate and rotational speed, and also a new equation was presented for it. Experimental results show that within the range of the investigated variables, increase in feed rate causes decrease in bone temperature and with the increase in rotational speed, the bone temperature changes are swinging.