Some bone removal needed for treating this below-gum cavity?

[Cathy French]

Hi,
I've been told I have a cavity just below the gum-line on a tooth that is root-canal filled and fitted with a crown. I was told the only way of treating it was to have some of the bone removed, and the crown extended. Does this sound right? It seems rather drastic and very expensive! The tooth is an upper tooth, next to a wisdom

 

[honestdoc]

Get a second opinion.

 

[MattKW]

Sometimes you can do a subgingival amalgam without removing the crown and all that, altho there may be some gum irritation; it depends on the case. Get 2nd opinion.