Long-term efficacy of a novel ribose-cross-linked collagen dermal filler: a histologic and histomorphometric study in an animal model.

Background: Degradation and loss of the three-dimensional shape are the major causes of limited functional longevity of dermal fillers made of natural polymers as collagen and hyaluronic acid.

Objective: This study assessed the functional longevity of a new ribose-cross-linked collagen filler during 24 months in an animal model.

Methods: Ribose-cross-linked collagen (Evolence, Colbar Life Sciences Ltd), glutaraldehyde-cross-linked collagen (Zyplast, Inamed Inc.