Pasteurization temperature and duration effect in normal bone osteocyte, porosity and biomechanics: in vitro studies

Pasteurization is a relatively easy and effective technique for limb salvage surgery in malignant tumors reconstructed by reusing tissue that has already been infiltrated by the tumor. The pasteurization process affects both tumor cell apoptosis and normal bone cell viability. The study aims to determine the optimal temperature and duration for pasteurization to effectively eliminate tumor cells while preserving the viability and integrity of normal bone. Laboratory experimental studies were conducted to evaluate cell viability, bone porosity, and biomechanical strength of post-pasteurized goat diaphyseal cortical bone. Cortical bones were divided into seven groups with different temperatures and durations. Variations in temperature (60 °C and 70 °C) and pasteurization durations (20, 30, and 40 minutes) were studied. Control groups were used for comparison. A significant difference was found in cell viability and porosity. The highest number of osteocytes was in the control group (80.4%). The osteocytes of the treatment group were the highest at 60 °C and 20 minutes (±77.29%). The lowest was in the group with a temperature of 70 °C and 40 minutes (64.66%). Higher porosity was found in those treated with higher temperatures and longer pasteurization. The biomechanical bending test showed that the force needed to break the bone sample was the lowest at 70°C for 40 minutes. However, the ANOVA statistical test showed no significant difference in all groups (p>0.05). Pasteurization can be used to maximize the eradication of tumor cells yet preserve the normal bone cell and biomechanical strength of the recycled bone autograft.