Hyaluronic Acid in Modern Cosmetic and Reconstructive Surgery - Hyaluronic Acid for Biomedical and Pharmaceutical Applications - page 142

8-16 months in the skin, depending on the age, the type of skin, the
muscle activity of the underlying tissue, the depth of the injection,
and the density of the material.
There are other absorbable fillers, such as collagen (bovine- or
porcine-derived) injections, calcium hydroxyapatite (biodegradeable
microparticles), poly(L-lactic acid) (PLLA) and non-absorbable fillers
such as Artefill (polymethyl methacrylate (PMMA) with collagen)
and silicone injections. Table 7.1 lists the most popular dermal fillers
available in the United States [18]. Compared to the above-mentioned
fillers, HA has the safest biological profile, and it is fully absorbable
and biodegradable [19]. Crosslinking of its macromolecular chains
increases its resistance to degradation by matrix metalloproteinases
and extends its life in the body [6].
Non-crosslinked HA may also be used for skin biorevitalisation, a
process of inducing fibroblast stimulation and regeneration of the
intracellular components that support the dermis Biorevitalisation
with HA is different from applications of HA as a filler. Although
both procedures provide a reduction in skin wrinkles and folds
biorevitalisation can also provide skin rehydration, treat skin
irritation, reduce muscle tone of the face and neck, correct skin
sagging of the abdomen, inner thighs and upper arms, reduce wrinkles
around the eyes, chest and upper lip, as well as remove the dark circles
around the eyes and shrink enlarged oily skin pores. This treatment
provides reduction in skin wrinkles and dermal folds and is used for
skin preparation prior to chemical peels or laser treatments [20-26].