What are the side effects and complications of Bellafill to uplift atrophic scar? Are the lumps I hear about caused by PMMA?

I am looking to have Bellafill injected into my atrophic nostril scar, the scar is about the surface area of 1cm by 1cm in a fairly circular shape and is indented mainly around the natural nostril line. It is prominent when I flare my nostrils and it hollows in. I know that Bellafill has permanent properties-PMMA which scare me despite it only making up 10% of the syringe. In the long run what happens to this material, because I don't want to be happy for 5 years and then need excision.Thanks