A. In both cases it all depends on the the quality of the tooth left. In the case of the tooth with the post it will be best if you have an implant. Having a new post and crown made will be money down the drain. Posts are the last thing that you can do to a tooth. Once this fails it really should be taken out. I would have to see an x-ray of the tooth where the crown has fallen off. Usually if there isn’t any decay it is possible to be crowned again
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