Children with cleft lip and palate have special concerns related to their teeth and jaws. Most have special dental problems. A cleft may involve the alveolar ridge (bone with teeth growing inside). Since the area of the cleft has no bone, there may be one or more teeth missing, the teeth may be defective in their shape or surface (enamel), or they may erupt into an abnormal position (rotated, tilted etc.) There may even be extra teeth. The teeth most commonly affected are the upper incisors and canines on the side of the cleft.