Top lip enhancement surgeon in Santa Barbara? Calcium hydroxyapatite: If you’re looking for something long-term but not permanent, Calcium hydroxyapatite injections could be for you as the effects last a whopping 18 months! Poly-L-lactic acid (PLLA): These injections are given over several months and last up to two years. Polymethylmethacrylate beads (PMMA): This bad boy …