For extra relief try throwing it in the freezer for a few minutes before your pup begins chewing. (kristenlevine.com)
The keys can also be refrigerated & stay cold long enough to provide extra relief for sore gums. (mommysbliss.com)
You can create extra relief when you place a gel pad in the refrigerator, which allows the cooling sensation on your nipples to help with the pain. (romper.com)