Liquid Nitrogen Refrigeration Autologous Skull Flap Repair Of Cranial Defects Experimental And Applied Research,

In order to study whether the autogenous skull bone flaps preserved in liquid nitrogen have the activity of living bone cells and whether these skull bsne flaps can be applied to repair the skull defects ,we select 8 mice,which are di vided into 2groups:in first group,the fresh tibia preserved in liquid nitrogen are taken as experimental.The tibia bone call morphology and en2yme activity are observed by histology and histo- chemistry .The experimental results are below: 1. In experimental group ( preserved in liquid nitrogen).the most bone pits are filled by bone cells and the crevices are normal. 2. In experimental group.the bone tissue high iodine acid Schiff reaction is positive:there is no significant difference between 2goups in ACP.AKP positive colourness in experimental group is less than that of control group.The experimental group has only positive reactions in some bone calls and the fringe of bone marrow. ? 3. The most bone cells of the experimental groupare observed by the electron microscope to be in normal morphology. In clinical practice.9 patients with skull defects were treated by the autogenous skull flap repair method and followed up 1 to 2years to have attained bone healing.No one had adverse reaction.The result is satisfactory.The skull bone flaps preserved in liquid nitrogen in another 6 patients were selected to undergo the study of histology.histochemistry and electron micro-scope . attaining the results consistent with animal experiment. 2 Conclusion: 1. The animal experiment verifies that the bone cells preserved in liquid nitrogen basically retain the living bone cell morphology and en2yme activity. 2. The clinical applications verify that the antogenous skull bone flaps retain living bone cell morphology and en2yme activety. 3. The skull defects were repaired by the autogenous skull flaps preserved in liquid nitrogen.This attained bone healing. 4. The method of repairing the skull defects with the autogenous skull flaps pveserved in liquid nitrogen has acquired satisfactory clinical effectiveness and is valuable to be recommened further.