Injectable fillers for facial soft tissue enhancement.

Soft tissue augmentation materials have been advocated for correction of post-surgical or post-traumatic facial defects, as well as for age-related folds and wrinkles. While autogenous tissues may be the safest option, they require a second operative site. Animal-derived or synthetic materials have been advocated since the late 19th century, and have waxed and waned in popularity. In recent years, we have gained a better understanding of the physical events that occur when material is placed within or below the skin. With this knowledge, we stand at the threshold of a new era, where soft tissue fillers can be designed and customized to suit the individual patient. This article will review the major materials that have been or are now advocated for use as soft tissue fillers, and will detail their relative strengths and weaknesses in order to give the clinician a better perspective when considering a material for soft tissue augmentation.