Experimental investigation of the temperature during bone drilling using thermocouples and numerical finite element analysis

Abstract

ABSTRACT The purpose of this study was to experimentally measure and simulate thermal diffusion in the surrounding of specific dental drills with cylindrical and conical drills. The investigation was performed under different drilling conditions, with and without cooling and at different revolution speeds. During the experimental investigation, drilling into a polyurethane (PUR) foam block, was performed with and without cooling, and at three different revolution speeds, 800 rpm, 3,000 rpm and 5,000 rpm. Finite element method (FEM) simulation of the thermal diffusion during drilling into PUR foam was also performed. As a result, different temperature diffusion was found in the surroundings of the individual drills. During specific drilling conditions, some of the drills produce very high heat, as opposed to the other tested drills. The results from the numerical FEM analysis are consistent with the experiments, and it is evident that the shape of the drill and the drilling conditions affect the results. The measurements in our experiment were performed under specific conditions that resembled mechanical drilling and did not match the reality of drilling in dental surgery, which is very often interrupted and the drilling force is reduced by the dentist’s hand. The actual temperature is probably much lower. The finite element (FE) analysis of temperature rise during drilling can be useful for shape optimization of the drill when the target function is lower in temperature.