Believe it or not, the distinctive dental office smell is made from cloves! Eugenol, the medicine used to numb toothache pain since Medieval times, is basically pure clove oil. The ancient Chinese used to chew cloves to freshen their breath before talking to the emperor.
Cloves are the dried buds of the myrtle tree. They are used as breath fresheners, pain relievers, perfume, and as a food seasoning. The leaf oil is what is used in Eugenol, applied directly to the gum for an analgesic. When mixed with zinc oxide, clove oil is also used for temporary fillings. No wonder cloves are listed as a calming food. I bet it numbs your insides, too! Euch!
(via Mental Floss)