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[The influence to maxillary growth by exposed bone wound in hard palate of rat].

OBJECTIVE
To confirm if denuded bone on lateral aspects of the hard palate of surgical repairs of the cleft palate is the main reason of causing disturbance of facial growth and to investigate the mechanism.


METHODS
48 SD rats were employed in the study. Among them 40 animals were divided into normal control and experimental group randomly. Normal control was not operated. Hard palate mucoperiosteum on the left side in experimental group were excised. Left hard palate mucoperiosteum in another 8 female three-week-old SD rats were excised with same method and were sacrificed at 2nd, 5th, 8th, and 12th day, respectively. The 8 rats were used for histological research.


RESULTS
The width of all left sides hard palates in experimental group was significantly narrower than right side, and demonstrated statistical difference. Chronic osteomyelitis on the denuded hard palate was observed.


CONCLUSION
The denuded bone wound might be a principal factor for the following maxillary growth deformity in cleft palate patients who received palatoplasty in childhood. The mechanism of causing the deformity might be wound and scar contraction, decreased blood flow and nutrition plus chronic osteomyelitis.