Effects of Multiple Drilling of a Bone by the Same Drill Bit: Thermal and Forces Analysis

Repeated use of the same drill bit during drilling causes wear of the cutting edges, which can lead to a significant increase in heat due to friction which is harmful to bone above 55°C. Few previous studies have examined the influence of several uses of the same drill bit on temperature rising. The objective of this study was to determine the influence of each drilling on temperature. T thermocouples were used to measure temperatures during each drilling test. Possible correlations of cutting parameters were studied. Tests were performed on a test rig measuring forces and temperatures during drilling of bovine bone. Effects of spindle speed (N), feed rate (Vf), and several trials (E) on temperature were measured. Temperatures increased significantly from E1 to E3. They decreased moderately with Vf. The best cutting conditions were at N= 200 rpm for Vf=60 mm/min and N= 100 rpm for Vf=30 mm /min drilling. At N> 200 rpm, they were very high. Temperature rising is significantly related to number of drilling (E), spindle speed (N), and inversely to feed rate (Vf).Funding Information: The author(s) received no specific funding for this study.Declaration of Interests: The authors declare that they have no conflicts of interest to report regarding the present study.