I've had a tooth extraction 10 days ago .. is it safe enough to smoke again?&can a dry socket form 10 days after an extraction ?

Not really safe: Smoking carries with it a large number of health risks so no doctor will tell you it's safe to smoke. That said, you are past the risk window for a dry socket at 10 days..

Smoke?: Only if you want to kill yourself. Chance of dry socket remote, but smoking irritates gums and contributes to gum recession, yellowing teeth and fingers, wrinkled skin on face, lung cancer (and you die by slowly drowning as lungs fill with tissue fluid), contributes to heart attacks, hardening of the arteries, stroke, kidney failure, kidney disease, etc. Make 10 days 20, then 30, then 40, then..

Smoking, Never Safe: The risk of dry socket or other complications after 10 days is very low. Regardless of age or health status, dental procedure there is no safe or risk-free level of smoke exposure. This a great opportunity to stop smoking permanently.