Of course they do. But can anyone give me a more reliable cite than about.com or ask.com to refute the bit of received wisdom which says they don’t?
How about the Departments of Radiology and Pathology, Children’s Hospital Medical Center, Cincinnati, Ohio.
The sphenoid and frontal sinuses are undeveloped at birth.
Although babies do have some sinuses present at birth, they are very small and most are undeveloped.
I have a theory that babies small sinuses are the reason they cry on planes. They cannot equalize the changing cabin pressure. This is based on nothing but pure speculation of course.
How about it?
Perfect; thanks.
The idea doesn’t make much sense. Equalization of pressure is carried out through the Eustachian tube that connects the mouth and middle ear. Undeveloped sinuses wouldn’t have much to do with it. In fact, they would mean that there are fewer cavities in the skull in which pressure would need to be equalized.
The Eustachian tubes of infants and toddlers are horizontal and short, and their palatal muscles aren’t developed enough to allow them to open the tubes as effectively as adults can. So while their small sinuses don’t cause a problem on planes, their small Eustachian tubes do.
ETA: Whoops - cite.