This instructable will show you how to make a decoction from whole cloves but I would be remiss if I didn't also mention that clove oil can be purchased from most pharmacies and is, due to the steam distillation process, much more potent and effective at relieving severe dental pain.
[However if you are suffering from severe tooth pain you should consult a dentist. Clove oil should only be used for temporary relief as prolonged use can deaden the nerve.]
Cloves have been used to treat toothaches since medieval times and knowing this trick can save you from experiencing a world of pain and discomfort. The active ingredient in clove oil is eugenol and this treatment is ideal for someone about to undergo a root canal or suffering from dry socket.
If you use clove oil to get relief from a simple cavity please do no do so repeatedly as it is possible to do more harm than good in the long run - only use this remedy to make the wait for your dentist's appointment go by more easily.
Step 1: Whole Cloves
Whether chewing a whole clove or using the oil you will want to spit - don't.
Wait a couple of minutes before rinsing your mouth out with water.
The analgesic effect should last a couple of hours and the bitter taste should subside in under ten minutes.
If you don't have access to clove oil and want to make a close approximation at home, grind whole cloves with a mortar & pestle, coffee grinder or blender.
You can also make clove tea to effectively relieve the pain with less mess - Thanks to putty1cat for sharing!