Any dentists can give me advice? Infection in root of root canal

[Harping]

I had root canal done 15 years ago. The xray now showing some grey area at the tip of the root on one side. Dentist said either redo root canal which he thought 50% chance will work. Or extract. Initially I thought maybe extraction is better to just get rid of tooth: but now I am worried about the gap . It’s first molar at the bottom so maybe it will be visible. Perhaps I should try and redo root canal? How bad is it to have infection in th root?

I've had this the root canal failed after 20 years they opened it back up gave me some antibiotics and then redid the posts and filling about a week later and I still have the tooth 4 years on.
Btw the dentist said a root canal is like any other filling and break down over the years allowing bacteria to get into the root hence the infection.
Really if you can afford to get the root canal redone it's worth trying if the dentist is suggesting it aa you could keep the tooth for years longer.

Thank you. Can you remember when you say the root canal “failed” what did they mean? Did it show as a grey area in the base of to root? I am wondering how easy it is to repair after this has happened

I've had two root canal treatments - one has lasted almost twenty years and the other over ten - they haven't failed yet. I don't remember what the x-rays looked like because my first sign of failure was an immense amount of pain.

Root repairs are far more involved than a standard root canal and take much longer. I wouldn't have anyone but an endodontist complete the treatment.

@Harping when I say that the root canal failed I mean that the filling material had degraded over time in the same way as a standard filling will and it allowed 1 of the posts to loosen and let bacteria down to the tooth socket and yes there was a greyness on the xray that the dentist said was the abscess and evidence of the deteriorating filling. Tbh like @reesiespieces the 1st I new there was a problem was when the pain started and had I not missed my yearly xray (due to lockdown) the dentist said he'd of picked it up before it got infected

Thank you hoardasurass That sounds similar to my situation