Cleft lip is commonly known as “hare lip” and “open mouth”, which refers to the cleft of the upper lip. Cleft palate, commonly known as “wolf’s throat,” is a cleft in the upper palate. Cleft lip and cleft palate are often associated with each other, and they are both malformations that are present at birth. It is the most common congenital developmental malformation of the oral and maxillofacial region, with an incidence of about 0.182%, i.e., 1 in 550 newborns may have a cleft lip and palate. Clinically, depending on where the cleft occurs, those that occur solely on the lip are called cleft lip; those that occur on the palate are called cleft palate; and those that occur on both the lip and palate are called cleft lip and palate.
Children with congenital cleft lip and cleft palate usually have not only facial deformities, such as cleft upper lip, collapsed nose, cleft roof of mouth, oral and nasal cavities, etc., but also important physiological functions such as sucking, swallowing, breathing and speaking, which often vary in severity depending on the site, extent and degree of deformity. In general, children with cleft lip alone often have more deformities than dysfunctions; children with cleft palate alone often have more dysfunctions than deformities, and children with both cleft lip and cleft palate have severe dysfunctions and deformities.
Children with cleft lip and cleft palate have difficulty sucking milk soon after birth because the mouth and nasal cavity are connected and there is no negative pressure in the mouth necessary for sucking milk. Although these children can get food nutrition with spoon, dropper or large-hole bottle feeding, most of them need longer time and patience when feeding, and they tend to swallow the air when sucking milk, so they often quarrel, have stomach pain, cry at night and cannot sleep peacefully after feeding. Due to the lack of nutrition and sleep, many of these children are healthy at birth, but lose weight soon afterwards. In addition, since the nasal and oral cavities are connected, cold air and dust cannot be filtered and warmed by the nasal cavity and enter the pharynx directly.
As the child grows up and begins to speak, he or she is unable to keep the airflow sufficiently inside the mouth (most of it escapes from the nasal cavity) and has difficulty making many sounds, often reluctantly using other organs and structures to make sounds, and the sounds made are so abnormal that they are difficult for outsiders to understand, so it is called cleft palate speech.