Many people have to undergo root canal therapy because of nerve death, which is in the interior part of a hollow teeth. Cavities when it erupts and contains neural networks, blood vessels and cells that deposit calcium in the inside of the pulp space and in the extension of the porridge along the roots. Teeth can die for a number of reasons. 

One deep decay, this has the most serious potential because it can cause infection and requires immediate care, combined with anti-biotics, to fight infection. A sore tooth may not mean a need for a root canal treatment. Some teeth are sensitive to cold because of gum recession, which describes the root of the teeth. Often the desensitization of the root area will solve the problem. 

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This case usually does not require anti-biotics because there is no bacterial involvement. In many cases, inner patches can cause calcification of pulp space. This can result in narrowing of blood vessels in the teeth, which leads to the loss of soft tissue vitality in the teeth. This again produces an increase in white blood cells at the root tip.

These white blood cells also remove dead tissue. When a patient presents with a sore tooth the dentist must ensure that a proper diagnosis is given.