Integrating a novel ZrO2 based end mill insert to evaluate thermal necrosis and bone surface roughness

Orthopaedic surgeries subject bones to mechanical and thermal stresses, impacting their structural integrity and healing potential. This study examines the thermal and surface integrity impacts of APMT 1135 modelled SS316L and biocompatible ceramic (ZrO₂) milling inserts during bone milling. Thermal stresses in orthopaedic surgeries can induce thermal necrosis, which is detrimental to bone healing. Temperature profiles (T_max and T_mean) were assessed, revealing ZrO₂’s peak temperature of 39.25 °C at f = 0.03 mm/tooth and s = 900 rpm. ZrO₂’s lower thermal conductivity resulted in reduced T_mean, critical for extended tool-bone contact. Surface roughness (Ra and Rz) analyses showed ZrO₂ generally achieving smoother surfaces than SS316L, except under specific conditions. These findings suggest ZrO₂ as a viable alternative for enhancing bone-implant interfaces and surgical outcomes in orthopaedics, emphasizing the importance of selecting optimal tool materials and machining parameters to improve bone surface quality, implant fixation, and healing times.