Evaluation of the biostimulatory effects and the level of neocollagenesis of dermal fillers: a review

Dermal fillers have become one of the main tools for soft tissue augmentation in the field of cosmetic dermatology. There are many types of fillers. While hyaluronic acid fillers are generally accepted as ones that fill in a space, they and other materials have been shown to have a biostimulatory effect on tissue through the process of a controlled foreign body reaction. Little research is available comparing their effects in terms of new collagen formation post administration. The goal of this review article is to evaluate the biostimulatory effects and the levels of neocollagenesis of poly-l-lactic acid (PLLA), calcium hydroxylapatite (CaHA), polycaprolactone (PCL), and hyaluronic acid (HA). A concise summary of the evidence is provided to assist clinicians in making informed decisions when deciding between the different types of widely available fillers.