Bellafill, like any filler, can sometimes result in granulomas. Depending on whose study you read, the risk of granulomas can be as high as 1 in 100 patients to as low as 1 in 5,000 patients. I have been injecting Bellafill (previously called Artefill) since early 2007 and had been injecting Artecoll as early as 1999 when I practiced in Canada before coming to the States. I have seen only two true granulomas. Both resolved with treatment.As for migration, that is something I have never seen happen. Given how the PMMA microspheres of Bellafill are locked into place by collagen encapsulation, migration should be nearly unheard of.All the best,--David C. Pearson, M.D.Pearson Facial Plastic Surgery®