Can other fillers such as Sculptra be used over same area of the face where Silicon 1000 was used previously?

Permanent fillers, particularly silicone, which has fallen into disfavor owing to its many potential and permanent side effects, as well as bioalcamid and artecoll (artefill) carry with them the risk of certain long-term or even permanent complications, which include the early or late development (even many years later) of nodules and granulomas at the treatment sites--problems very difficult to manage. Since late developing complications--even up to a couple of decades afterward--are certainly well-described possibilities, many physicians, myself included, are reluctant to inject any of the newer and much safer, natural fillers and volumizers into the same areas previously treated with permanent fillers, primarily out of concern that this may trigger the onset of just such delayed reactions--essentially out of a consideration for "Let sleeping dogs lie." And this should serve as a word of caution to other readers who are first considering having permanent fillers injected into their faces.This question also segues me to a word about Sculptra, a product that I stopped using more than a half dozen years ago. Sculptra treatments tend to be expensive, generally require a series of at least three treatment sessions spaced at several week intervals to realize benefits, and characteristically do not provide any immediate improvement. Volumization takes place over time as a result of stimulating new, native collagen and elastic fiber production (neocollagenesis, neoelastogenesis). Results last about two years. Other injectable volumizing fillers, on the other hand, such as Voluma XC, give immediate results (usually result in a "Wow!" effect) after just one treatment. Results, likewise, may last up to two years, and use of these volumizers also promotes neocollagenesis and neoelastogenesis.

Sculptra, which is FDA approved for aesthetic facial volume addition, encourages gradual collagen formation through a series of deep tissue injections.  Silicon 1000, which is not FDA approved for aesthetic use, has been used by a small percentage of injectors as a filler in a technique similar to many FDA approved fillers (Restylane, Juvederm, Radiesse, etc.).  Even proponents of Silicon 1000 would generally not advocate its use as a volumizer, because of the tendency of Silicone to shift, form granulomas, and other aesthetic nightmares. In short, Sculptra and Silicon 1000 aren't comparable at all.