Where my tooth was pulled thought there was piece of tooth.came out and it was spongy,no smell and disintegrated in fingers.more is left.is it gauze?

Extraction fragment: It could have been a small fragment of decayed tooth or a bone fragment (or something else). I wouldn't be concerned about it. Just make sure your dentist sees you for a follow up visit to check healing. If you have any other questions or concerns call and speak to your own dentist.

Gel foam : It can often be a variety of materials that we use to try to pack in an area to stop bleeding, an example is gel foam. It will usually dissolve on its own if it is not removed.

No: How long has it been since the surgery? If recent, may be part of the clot that formed in the extraction site. If it's been a while since the surgery may be a spicule of bone. If concerned, return to the Dentist or specialist that did your extraction for post-surgical reevaluation.

Probably bone : Probably bone spicule or calcified areas of the clot. Check with your dentist to evaluate the area and discuss ant issues.