Abstract
In order to clarify the cause of inhibition of maxillary growth in the cleft palate, the maxillary growth after resection to the midpalatal suture was studied quantitatively in rats.
The animals were randomly divided into group A of untreated con t rol, group B with elevation of the palatal mucoperiosteum, group C with bone resection of the palate on except for the midpalatal suture, group D with bone resection including the midpalatal suture. In each group, serial maxillary casts were made for subsequent measurements of the palatal width.
The results are summarized as follows.
1. When compared with the untreated group, the lateral growth of the palate was most severe in group D; which was followed in order of severity by group C and group B.
2. Elevation of the palatal mucoperiosteum had the least effect on the lateral growth of the palate.
3. In group C, the rate of inhibition showed a tendency to decrease 40 days after operation.
4. Resection to the midpalatal suture produced the most prominent and long lasting inhibition of the bilateral growth of the palate.
5. The midpalatal suture defect was found to have a much greater effect on the lateral growth of the palate than the surgical intervention of the palate itself.
