BACKGROUND:With the development of tissue engineering, porous bioceramics are more and more used to repair bone defects. Current research focuses on the biological synthesis of this bioceramics and its performance evaluation.
OBJECTIVE:To discuss the preparation of a new kind of bone cement and to determine its physicochemical properties and biocompatibility with osteoblasts.
METHODS:Biphasic tricalcium phosphate powders were prepared using co-precipitation method. The powder was turned into granular stuff by arabic gum. After sintering, porous hydroxyapatite/tricalcium phosphate bioceramics were harvested, and then mixed with alpha-hemihydrate to prepare the bone cement.
RESULTS AND CONCLUSION:X-ray diffraction confirmed that the synthetic substance was a kind of biphasic calcium phosphate ceramic having a porous structure. The bone cement could be in the plastic state within 3 minutes. The curing time was 15 minutes, and the curing temperature was 36.5℃. The maximum compression strength was 5.82 MPa, and the MTT toxicity was level 0. Osteoblasts could grew wel on the material surface.

Objective To simulate the dynamic procedure of bullet damage to the three-dimensional(3D) finite element(FE) model of mandible from different angle with computer-aided engineering.Methods A mandible was scanned by thin-layer CT,and then CT images were analyzed and managed with Dicom standard and Mimics software.At the same time,a simulation of the 3D FE model penetrated by a 7.62-mm bullet was carried out through LS-DYNA software from different angle.Results A 3D FE model of human mandible was established with highly-identical geometric size,and the dynamic process of bullet damage to the model was successfully simulated.The results of this work indicated that the exit wounds in model tended to be larger than the entrances resulting from the same shot.Conclusion Thin-layer CT and Dicom standard can improve the efficiency of establishment of a more precise 3D FE model of mandible.The procedure of bullet damage to the mandible can be simulated by the finite element.