Root canal failure should be immediately brought into the consideration of the dentist that did your RCT. Dont try any medications prior prescription. You can try some home remedies like:

1. Soak cotton dipped in two to three drops of clove oil and 1/4 teaspoon of olive oil
2. Apply a dab of vick vaporub on the outside of the cheek where tooth hurts. Place a paper over the pillow and lie down on that side.

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