7 days ago all my top teeth pulled with sutures.today the stitches started falling out. i saw a big hole with a white spot in it.is it a dry socket?

Post extraction: It is common for sutures to come out after about a week. This is part of normal healing. If you had a dry socket you would have intense pain. Since you didnot say anything about pain, it is unlikely that you have a dry socket. Call the extracting dentist with you questions about healing concerns.

Not dry socket: There are several things that this could be: 1- Gelfoam - a resorbable material we use to minimize bleeding. 2 - Plaque on the blood clot - use gentle salt water rinse 3 - possible that you are seeing bone 4 - If not in sever pain - just follow directions. If pain is severe, call your dentist Good luck