ABSTRACT
Objective: To study the microcosmic and pathological changes of compressed premaxillary suture in rabbit models with the cleft in premaxilla.Method: 12 male New Zealand rabbits, at the age of 3 weeks were designed randomly into 3 groups with 4 in each. In group 1and 2 a retropress force of 2.24 and 1.12 N was applied on the maxilla of the animals respectively. The other group was the control. The experimental animals were killed and compressed premaxilla suture specimens were examined by microscopy and electron microscopy 3,6,9 and 12 weeks after operation respectively. Result:In group 1 disturbance of microstructure and degeneration of osteoblasts were observed 3 and 6 weeks after application of the compress force. In control group normal bone structure and development of maxilla were observed. The microcosmic changes in group 2 were similar to those in group 1, but slighter. The microcostructure in the compressed premaxilla tended to be normal 9 weeks after operation. Conclusion:Compress force on premaxillary suture may result in limited pathological changes of the bone during early developing stage.