Usually a crown comes out if it has lost its support(surface), due to secondary carries under it. Or if it is newly fixed , there may be high point- but that may not be your case.
Secondly, there might be micro leakage under the crown leading to fluid seepage .
Basically there are many reasons for the crown to come out.
So please visit the dentist, if the toot is carious , 1st get it treated.
Cost varies depending the treatment needed.
Thanks
Answered2017-06-14 09:24:13
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