The actual role of hyaluronic acid-based and calcium hydroxylapatite soft tissue fillers: a guide for a practicing dermatologist.

Soft tissue fillers (STFs) together with botulinum toxin have profoundly improved our possibilities to rejuvenate the face and other parts of human body. Among many types of STFs currently used for esthetic and medical indications in routine clinical practice dominate hyaluronic acid-based STFs and calcium hydroxylapatite. Collagen fillers (bovine, porcine and human) are gradually leaving the market replaced mostly by hyaluronic acid-based STFs. This review presents an overview of the physicochemical properties, mechanisms of action and techniques used for the correct placement of hyaluronic acid-based STFs and calcium hydroxylapatite and the most common esthetic indications for these fillers. Finally, we present the recent data on their efficacy and most common complications encountered.