Abnormal Vomer Development in Human Fetuses with Isolated Cleft Palate

Objective The aim of this study was to elucidate the prenatal human development of the vomer with emphasis on the vomeral footplate and to assess vomeral morphology in fetuses with isolated cleft palate. Material and Methods Nine human fetuses of which four were normal (menstrual age [MA] 13 to 21 weeks) and five with isolated cleft palate (14 to 19 weeks MA) were studied. Midaxial cranial tissue blocks from the fetuses were cut frontally in 4μm serial sections. Sections were stained with toluidine blue in 30% ethanol. Results From 16 weeks MA, the vomeral footplate of normal fetuses was formed from bilateral ossifications located below a U-shaped vomeral body. Later in development, an osseous connection was found between the footplate and the vomeral body. Neither bilateral areas of ossification below the vomer nor a vomeral footplate was observed in isolated cleft palate fetuses. Conclusions In normal fetuses, the base or footplate of the vomeral bone appears from 16 weeks MA in frontal sections. In fetuses with isolated cleft palates, with no connection between the nasal septum and the maxillary processes, this vomeral footplate does not develop in the period observed (14 to 19 weeks MA).