THERMAL ANALYSIS IN DRILLING OF EX VIVO BOVINE BONES

Abstract

Bone drilling is a common procedure in Medicine, mainly in traumatology and orthopedic procedure for fractures fixation and in reconstructive surgery. The success of this surgical procedure is dependent on many factors, namely, on heat generation control during the bone drilling. The main concern in bone drilling is the mechanical and thermal damage of the bone induced by inappropriate parameters such as drill speed and feed-rate during the drilling. This study focuses on the temperature generated during drilling of cortical bone tissue (bovine origin) and solid rigid polyurethane foams with similar mechanical properties to the human bone tissue. Different parameters such as drill speed, feed-rate and hole depth were tested. All results showed that improvement of the drilling parameters and the drill temperatures can be estimated. It was concluded that when the drill speed and feed-rate were higher, the bone temperature increase was lower. The obtained results of temperature in the drilling process of polyurethane foam blocks or bovine bone were compared with a good agreement in between both.

The influence of the chosen in vitro bone simulation model on intraosseous temperatures and drilling times

“…Drilling is a very complex machining process, cumulating the effects of cutting and material extrusion 1 . The heat generated is a result of friction between the drill bit and the cutting surface of the drilled hole and bone chips and fragments 2 .…”

“…Thermocouples allow direct temperature measurements inside the bone, but they detect only a single temperature point and need preparing pilot holes. Infrared thermography detects an overall thermal profile including also the measurement of leaking heat; however, it detects only the surface temperature, without predicting the temperature of the actual drilling site 1,2,6,11 . According to Möhlhenrich et al .’s systematic review, 18 studies used thermocouples, and 7 used thermal cameras of the involved, analyzed studies 12 .…”

“…As Fernandes et al . (2017) wrote, to date just a relatively few numbers of papers have directly compared heat development of drilling in biological tissues with synthetic bones 1 . According to our best knowledge, this is the first attempt to compare porcine and bovine ex vivo models simultaneously with different density polyurethane blocks and with fresh human cadaver bone by the same bone drilling procedure (common in oral surgery bone removals 3 ).…”

Computational model to predict the temperature distribution produced by bone cement

“…The higher the initial temperature, the higher rate of heat transfers from cement to the bone [9]. Others authors focused on empirical models for the prediction of heat generated using experimental and computational results [10]- [14]. In this paper a two dimensional thermal and transient model based on finite element method was built to predict the temperature field produced by cement polymerization in metastatic bone tumor lesion.…”

The heat transfer modelling for bone metastatic lesion minimization using two different cement types

“…Different authors studied the exothermic reaction of cement polymerization and reported in different publications predictive results regarding the temperature rise and residual stresses using time-dependent polymerization function [2], [4]. Others proposed empirical models for the prediction of heat generated using experimental and numerical tests [3], [5]- [9]. There are studies in the literature that point out thermal necrosis in cortical bone, usually when it reaches a temperature of 47ºC for 1 min [10]- [11].…”