How do jet time, pressure and bone volume fraction influence the drilling depth when waterjet drilling in porcine bone?

The established relation between the machine settings and drilling depth allows surgeons to adjust jet time and pressure for the patient׳s BV/TV to drill holes at a predetermined depth. For developers, the relation allows design decisions to be made that influence the dimensions, flexibility and accuracy of water jet instruments. For a pressure of 50 MPa, the potential hole depth spread indicated by the 95% confidence interval is <1.6 mm for all tested jet times. This maximum variance is smaller than the accuracy required for bone debridement treatments (2-4 mm deep), which confirms that water jet drilling can be applied in orthopedic surgery to drill holes in bone with controlled depth.