Rheologic properties of soft tissue fillers and implications for clinical use

Abstract

The use of injectable soft-tissue fillers has become an essential tool in esthetic rejuvenation. Rheology, the study of flow of matter, helps to understand the function of these products. The purpose of this article is to review the rheologic properties of soft-tissue fillers currently available in the United States and to evaluate how these properties relate to clinical performance. This article explains basic rheologic terms and describes how rheologic properties of specific soft-tissue fillers affect filler performance. The currently available soft-tissue fillers have unique rheologic and physicochemical properties that influence performance and cosmetic outcome. These properties determine that filler product is most appropriate based on degree of soft-tissue defect and anatomic location. It is imperative for physicians to have an in-depth understanding of the rheologic properties of soft-tissue fillers in order to appropriately select and utilize these products for the desired cosmetic outcome.