Dead Tooth Nerve From Shingles

[omits]

two of my teeth suffered nerve necrosis from shingles. One has been removed. The other os a crowned molar right at the back and gives low pain which is no problem as such. But the other day when brushing the gum below the tooth is sensitive. I don't really want the tooth removed but worried now it will start to rot. it has been X-rayed and the nerve is dead.

Anyone hd this problem and got away with leaving it in place?

Many thanks.