Silly question, maybe. Does the baby just wear the necklace, or chew on the beads?
Also, a lot of companies sell amber bracelets and ankle bracelets for the same purpose and they are cheaper, but I have read that the jewelry should be as close to the origin of pain as possible to work, so for teething, you'd need a necklace.
The baby just wears it and their bodies warm the amber which releases trace amounts of succinic acid onto their skin where it is absorbed and relieves pain.
Some moms find that the teething necklaces don't work for their babies. If you buy one from Inspired by Finn, however, she will guarantee them, so you can send it back if it doesn't work for you.