On-line measurement and monitoring of pulsating saline and water jet disintegration of bone cement with frequency 20 kHz

Abstract This paper deals with performance analysis of disintegration of polymethylmethacrylate using pulsating liquids jet with different density with frequency 20 kHz using condition monitoring. The influence of the liquid on the cutting depth was studied by using contactless measurement device MicroProf, FRT. The cutting depths were compared to studies that used a continuous water jet to assess the volume flow reduction. On-line condition measurement was used for controlling the disintegration process without compromising the structural integrity of neighbouring materials. With a flow rate of 0.54 l/min, a maximum disintegration depth of 1.3 mm and material removal of 0.4 mm 3 was obtained using physiological saline and 1.1 mm and 0.2 mm 3 for water. Continuous jets required approximately 1.0 l/min to reach similar cutting depths. Hence, a pulsating liquid jet enhances the cutting capacity with reduced flow rate. Signal strength for individual pressures 7-10 MPa is not significant, but signal increases during significant bone cement removal. The results open new avenues for research a minimally invasive and non-thermal technique for on-line controlled processes for medical purposes.