Thank you for this great question which many patients contemplating or undergoing this procedure are sure to ask. Fat transfer is an incredibly effective way to restore volume to the face. Harvested fat is a living graft that requires good blood supply in the recipient site to survive and become incorporated, and once it does, it pretty much stays there permanently. This is one of the greatest advantages of fat compared to other volumizing products such as Fillers and Sculptra. The percentage of fat that survives out of the total that is injected is called the "take rate". The best location for a fat transfer is in the cheeks, lower eyelids, temples and forehead. Unfortunately, because the mouth moves so much, the take rate on injected fat around the mouth is generally very low (think of it as a blood vessel aiming for a moving target). I still inject around the mouth and lips during a full face fat transfer because even a 10% take rate is better than 0, but I always educate my patients not to expect a great deal sticking around. I usually recommend laser or chemical peel skin resurfacing for wrinkles around the mouth, although patients need to be aware of the increased down-time associated with such treatments (atleast 10-14 days of swelling and 24/7 occlusive ointments and the possibility of prolonged redness). Fillers are extremely popular around the mouth to treat the lines you're referring to, although longevity varies between 6 months to 1 year. Hope that helped! Best, Dr. Roy.