Polylatic Acid

Since 2005, the brand of polylactic acid released by the National Health Surveillance Agency (ANVISA) in the US has been released by the US Food and Drug Administration (FDA) since 2004 for use in lipodystrophy in seropositives and in 2009 for other aesthetic uses.

One of the important features of this product is that, unlike other fillers, polylactic acid does not act by filling the applied region. This product is the only one on the market that, while included as a filler, acts by stimulating the host’s own collagen, gradually correcting tissue depression as it is applied.

Polylactic acid is of synthetic origin, ie it has no animal origin. It is also biocompatible and bioresorbable, that is, it has the property of being entirely resorbable by the body, helping to stimulate the patient’s own collagen, improving expression wrinkles and promoting the harmonization of the treated area. These results lead to a lifting effect, not only by reducing depressions, as some products remain inert in the applied area, but also by the patient’s own neocolagenesis.

Polylactic acid technical information

Polylactic acid, under the acronym PLLA, is a synthetic biocompatible and biodegradable 1 – lactic acid polymer because lactic acid is naturally formed in the human body and metabolized and is subsequently eliminated by urine, sweat or reused as an energy form. Lactic acid can be converted to glucose, glycogen, protein or even oxidized, resulting in Co2 and H2O in the Krebs / citric acid cycle.

The above scheme demonstrates the transformation of lactic acid to polylactic acid, where degradation follows the same patterns: lactic acid “released” or degraded by the Krebs / citric acid cycle pathways.

The marketed product is formed by mannitol (to improve lyophilization) carboxymethylcellulose as emulsifier, and PLLA (polylactic acid) particles. Polyactic acid particles, as well as other fillers such as PMMA or hydroxyapatite, are between 40 – 60 microns in diameter, ie small enough for use with needles (recommended by the manufacturer 26 g) and large enough for avoid phagocytosis and capillary permeability.

The mechanism of action begins with a subclinical inflammatory process, following the mechanism of collagen production, which depends directly on the inflammatory process, involving the collagen-depositing fibroplasts that result in a gradual effect on skin filling.

The inflammatory response varies according to the physical characteristics of the implant to be used, regarding size, shape, surface and chemical characteristics, such as PH, electric, hydrophilic or hydrophobic charge. This reaction also varies according to the time, place, and amount applied, factors that will be decisive in determining the degree of inflammatory process and fibroplasia that results in collagen.

PRODUCT QUANTITY – SESSION INTERVAL

The amount of product to be used per application ranges from 0.2 to 0.3 ml of product per cm2. Unlike other filler products, the result of polylactic acid is gradual and may take between six (6) and eight (8) weeks for total collagen production (neocolagenesis), resulting in up to two (2) years.

The number of treatments varies from two (2) to three (3) sessions, according to region and doctor’s indication. The interval between them varies between four (4) and six (6) weeks.

The application plan varies by region, although initially indicated for deep dermal application, there is nothing to prevent it from being used justly periosteum in the zygoma region or even subcutaneously in patients with severe malar region lipodystrophy.

COMPLICATIONS:

Overall, the application of PLLA has shown low complication rates, such as bruising and edema. It is, however, self-limiting in cases of palpable nodules or granulomas, which usually occur by error in the application process.

Problems can be verified by poorly applied fillers, such as applying too shallowly, placing too much product, or just