Postnatal descent of the epiglottis in man. A preliminary report.

The function of the epiglottis in adult man is unclear. However, during early infancy the epiglottic cartilage appears to play an important role in separating the upper respiratory tract from the upper digestive tract. This separation is accomplished by approximation of the epiglottis to the palate, providing a continuous airway from the nose through the larynx into the trachea. This structural arrangement, however, is uniquely lost in man during postnatal development. Maturational descent of the epiglottis, found to occur between 4 and 6 months of age, is verified by cineradiography. This structural change, requiring a reorganization of respiratory function, represents a discrete developmental event manifesting the potential for oral tidal respiration from a pattern of obligate nasal breathing. This period, four to six months postnatally, interestingly coincides with the peak incidence of sudden infant death syndrome (crib death), which similarly occurs at 3 to 5 months of age.