Kebbit teeth are dropped from Sabre-toothed kebbits after a successful deadfall trapping. The teeth can be used with a pestle and mortar to award the player 1 Herblore experience and create Kebbit teeth dust, which is used to make a Hunting potion in the Herblore skill. After Fairy Tale III - Orks Rift kebbit teeth are one of the required items to get a Tooth creature pet. The Tooth Fairy will also directly buy spare sets for 1 coin.
The Herblore Hunting potion info refers to Kebbit teeth dust as 'ground sabre-toothed Kebbit teeth'. These are the same item.