Aside from the advances made in laser and light-based technologies, no other subset of dermatology has expanded or advanced in the past two decades as much or as quickly as the field of tissue fillers. As we will discuss in this chapter, early products used were rudimentary, often allergenic, and cosmetically inferior when compared to the products that are available in the U.S. and European markets now as well as those in late-stage development at the time this chapter was written. In fact, advances in hypoallergenicity; stability though cross-linking; and newer, more biocompatible filling agents are coming through the pipeline so quickly that the reader may see only a brief lag after reading this chapter to a time when agents covered in our “Future Directions” section become available in certain global aesthetic markets.

In the following discussion, we will first provide a historical backdrop for the development of early filling agents, their uses, benefits, and drawbacks. We feel it is important for current practitioners who may not have used earlier products to know how the field has evolved. This becomes quite important when we see, like many fashions, that trends in tissue filling agents come and go, and some become reborn again in the future because of advances in science that eliminate certain side effects or drawbacks to a particular product.