This Iron Tooth has the rune of purity inscribed on the side in silver dwarven script
Greater Purifying Tooth
How to use— Place tooth in an empty socket and it will attach to your jaw and it will work
Special— Anything put into your mouth loses all harmful property’s, purifying food and drinks of poison and other harmful substances.
Special— Gives you a +10 fortitude save against poisons and drunkenness
Lesser Purifying Tooth
Special— Gives +5 fortitude save vs poisons and drunkenness.
Cost: 6,000 gp
There are many of these in existence, it was first invented by the dwarves so they could drink more.