Pacifier inquiry: "Cotton in the nipple"?

[Kaliborio]

Hi folks,

Hope you are well.

Someone has just written me on my tumblr, asking why a specific variety of pacifiers, "German 'big nipple' pacifiers," "have cotton in the nipple". Attached is an image of the variety of pacifier they're referring to. It has a bunch of results on Google Image Search but I'm not sure if it's a single specific product line, a single brand, or what the story is.

I've never owned one of these so I don't know if they have cotton in the nipple, and if so, why. Does anybody else know? Thanks so much in advance!

[Little Sherri]

I believe the idea is that it contributes to the "memory" of the nipple, IE that it tends to auto-inflate after compression. Larger nipples or ones comprised of less stiff materials like latex can tend to go flat and then not return to their original shape as readily as a smaller, stiffer silicon nipple would. However, that said, I don't completely understand how this works - if the cotton is hermetically sealed or what. In my size 6 silicon pacifiers, humidity and condensation can become visible within the nipple with use, so I disassemble them periodically and sanitize them and let them dry out.