It seems from your description that the unsupported structure of a tooth with the large cavity has broken off and has created a sharp edge.
You should visit the dentist as soon as possible so that the right treatment can be instituted immediately and most likely this treatment is going to be in the form of root canal treatment of the tooth based on your description. The clinical evaluation and x-ray of the tooth will be the best deciding approaches.
Regards
Answered2017-10-06 17:36:28
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