What are the dangers of buttock implacts/injections fat grafting? and which one is most safe? should i worry about getting them?

Neither: These are technique sensitive procedures. As such, they are potentially problematic.

Both safe: Fat grafting to the buttocks, also known as a brazilian butt lift, transfers fat from an unwanted area to the buttocks. The most common complication is loss of the injected fat. It is normal to loose 30-40% of the injected fat. Implant augmentation is very safe when performed by an experienced surgeon. The best placement of the implant is intramuscular which decreases the risk of seromas.

Difference: Both buttock augmentation procedures are safe with minimal risks if conducted by an experienced surgeon. The procedure and recovery process differs for each technique. The fat grafting is non-invasive whereas the implants require a surgical incision in the anal region, prone to infection. Discomfort from implants is higher due to the surgical implications vs injections from fat grafting.

BBL over Implants: Both surgeries carry some risk, as with any surgery. However, a brazilian butt lift typically carries a lower complication rate and the results are much better than implants. Be sure to consult with a board certified plastic surgeon to determine what's right for you.