Traumatic indented scars, like those from chicken pox, acne, and surgery can be improved by subcision and volumizing fillers. Subcision breaks up tethering scar tissue under the depression, freeing it up and allowing it to "float" to the surface. Usually a series of treatments are needed (generally about four spaced at four to six week intervals) for optimal results. A volumizing filler, such as Radiesse, can be injected either at the time of subcision or a later date to further aid in elevating the base of the scar upward. For more information of subcision and volumizing fillers for scar treatment, I suggest you check out the archives of Realself.com.