I had root canal treatment on a tooth (#11) about 9 years ago due to a severe periapical abscess. it has been fine since but i noticed the tooth has recently been appearing more gray compared to the surrounding teeth. does this need to be looked at?

After a root canal, your tooth is not vital, no nerve or blood supply. Your tooth is now subject to a fracture unless a crown is placed. Over a period of time the tooth color starts to fade and becomes darker because it is no longer a live[vital tooth]. It is always best to have a crown made to protect the tooth from breaking and to restore its normal color. Have a crown made now.

It is normal for a tooth to darken after root canal therapy. The grey color, however could be from recurrent decay under a restoration. It would be wise to have the tooth evaluated.

Absolutely. There are multiple possibilities for color change. An examination will allow for an informed answer. Yes, please see your Dentist sooner rather than later.