OBJECTIVETo quantitatively compare the relationship between the congenital cleft palate and development of the palatal shelf.

METHODSFifty two pairs palatal shelves were macroscopic measured, and 60 series coronal sections were microscopically measured, which were precisely orientated in the coronal plane and serially sectioned at 7 micro m thickness. With the aid of computer imaging analysis system the widths and areas of the palatal shelves in vertical and coronal direction, the maximal areas of the palatal bone and palatal process and alveolar process were measured and compared quantitatively between the cleft group and non-cleft group.

RESULTSThe widths and areas of palatal shelves in cleft foetuses showed significant reduction macroscopically and microscopically as well as the maximal areas of the palatal bone, in addition, both of two processes of the maxilla showed significant developmental deficiency.

CONCLUSIONSThe palatal shelves show significant developmental hypoplasia in three dimension directions, which have significant correlation between palatal cleft and trisomic condition.