Cleft lip and palate: Developmental abnormalities of the face, mouth and jaws

The cleft of the secondary palate does not disrupt a basic growth mechanism of the upper jaw, hence the maxillary complex has normal growth potential. In normal palate, muscles are oriented transversely and meet in midline, while in cleft palate the muscle fibers are oriented in the anteroposterior direction inserting into the posterior edge of hard palate and cleft mucosa.