It took my niece's a little more than a week to be stable again. Avoid hard or sticky foods to help speed the process and the roots should get strong again.
If a tooth is going to tighten up, it will occur within two weeks. The sooner a dentist is seen after trauma, the greater the chance of saving the tooth.
Just to be safe it might be a good idea to get a second dentist to look at his x ray. If the tooth is not moving around than it probably is okay. It may take a couple of weeks for everything to go back to normal.
Generally speaking as long as the tooth has begun to successfully re-root, than it should be perfectly stable within two to three days. Anything much longer than that and more extensive repair may be necessary.
