Poly-L-lactic acid differs from the other fillers in that it is dependent on the host immune/reparative response to accomplish filling. Other similar products include silicone and polymethyl-metracrylate (neither is currently FDA approved for soft tissue augmentation). Unfortunately this mechanism of action for augmentation has two potentially negative effects inherent to the nature of the response: (1) the host immune system can respond less than optimally causing less augmentation then desired; or (2) the host immune system can respond overexuberantly creating granulomas or lumps. In the mouse model histologic evaluations at 1 month has shown: (1) polylactide surrounded by 100 (im thick capsule; (2) mononuclear cells, macrophages, fibroblasts with increased collagen; and (3) mature vascularized fibrous capsule. As reported by Gogoleski et al, at 3 months there are: (1) Decreased cell numbers and increased collagen fibers with a capsule thickness of 80 |J.m. At 6 months the cell numbers decreased and the capsule thickness is only 60 |im. Lemperle studied the histologic reaction in his own forearm to poly-L-lactic acid. At 1 month there was fine capsule around implant. At 3 months the Sculptra microspheres were intact, and surrounded by macrophages and lymphocytes. At 6 months the Sculptra microspheres were degraded and deformed, and surrounded by macrophages and giant cells. At 9 months the Sculptra microparticles completely degraded and there was no detectable scar tissue. Poly-L-lactic acid is a filler in which mechanism of augmentation has been proposed but not proven. Beljaards et al report the histology from side effects or complications has shown fibroblast giant cell granulomas but no new collagen. The immune system has an intergral role in fibroblast behavior so the response to this product in the immune-competent population might be quite different to that of the immunocompromised (HIV) population. The mechanism of augmentation for this product, particularly the short- and long-term tissue effects in immunocompetent patients, needs to be better characterized by further study.

PLLA (Sculptra) is a synthetic polymer which is resorbable, biocompatible, and biodegradable. It has been used for several years in multiple medical devices and is a component of vicryl sutures. PLLA can be injected into the deep dermal tissue or subcutaneous tissue. The area to be filled should be undercorrected. After injection, gradual degradation takes place by hydrolysis while gradual deposition of collagen occurs.

The initial correction, due to implantation of the PLLA or Sculptra decreases over the next few days as the diluent is resorbed. The area treated with Sculptra will then slowly refill as the tissue reacts to the implant. A gradual increase in the volume will continue to occur over the next few months.

The side effects of Sculptra are similar to those of other injectables and include erythema, edema, and bruising at the injection site. Palpable but nonvisible subcutaneous nodules have been noted in some patients, which can resolve spontaneously. These nodules on the lip may be due to overcorrection. Massaging the treated area after injection may reduce the incidence of this side effect according to Sculptra reviews. Rare cases of sterile abscess, late granuloma formation and hypersensitivity reactions have been reported.

Sculptra is injected with a different technique than the other wrinkle fillers. It is layered as a deep dermal and subcutaneous soft tissue filler that is used mainly to correct volume deficits rather than wrinkle correction alone. The technique of Vleggar demonstrates injection with a criss-cross pattern to lay down a uniform matrix for new collagen to be deposited in the deep dermis. To correct naso-labial folds, the entire lower facial area should be blended to augment tissue and provide a volume-enhancing effect. That not only corrects the furrow but also redefines the lost volume in surrounding skin and soft tissues. A 27 gauge needle is used to implant the gel into deep dermis and subcutaneous tissue in a criss-cross pattern. No more than 1-2 ml is injected with undercorrection. The area is then massaged and iced to decrease inflammation. Two or three repeat procedures are performed for full correction. The product has been found to last 2-4 years in large Sculptra review trials.

A new off-label indication for the use of PLLA is as a pre-treatment of the deflated face prior to other modalities that might otherwise be unsuccessful because of the poor tissue quality or severe redundancy. This works especially well in conjunction with radiofrequency tightening, threadlifts and traditional face lifts when PLLA is injected in two or three sessions, at least several months previously.

Fibroplastic fillers represent a change in paradigm from previous direct fill agents used for volumetric restoration.Although not offering instant gratification, often requiring 4-6 months to achieve correction, patient satisfaction remains high. The predictability and significant duration, up to 40 months, with injectable PLLA is also unique. Adequate dilution and placement, as well as proper technique followed by massage is essential to optimize outcomes and avoid nodules.

Originally the vial containing 150 mg of PLLA freeze-dried powder with excipients was diluted in 3 ml of sterile water. Current recommendations call for dilution with 5 ml or greater of dilutent. Many authors recommend 4 ml of sterile water or bacteriostatic saline and 1 ml of 2% lidocaine with epinephrine (which may reduce post-injection bruising). Some authors, including Vleggaar and Bauer, and Lam et al recommend greater dilutions (8-12 ml), in areas such as the hands and neck. The lyophilized powder should be reconstituted no less than 2 hours prior to injection, but most users now recommend 12-24 hours prior to use. Just before withdrawal from the vial PLLA needs to be vigorously shaken, and then again, in the syringe just prior to injection. Injection with a 1 cc luer-lok syringe and a 25 gauge 1 in needle affords excellent control. Smaller gauge needles are prone to blockage with the particulate material.

Topical anesthesia should be applied 20-30 minutes prior to treatment. Areas most frequently and successfully treated are the hollow of the cheek, nasolabial and prejowl folds, malar area, suborbital and temporal areas. The lips and nose are to be avoided. Unlike many ‘immediate’ fillers, PLLA is not injected directly into a fold to achieve correction, but rather in a matrix-like cross-hatching pattern. The pattern of injection is much like a scaffold or that of rebar in reinforced concrete, where an interlocking network is created as a foundation. PLLA is injected subcutaneously - not in the dermis - by means of a reverse threading technique, where the needle is passed at a 45-degree angle through the skin and then fully inserted in the subcutaneous plane parallel to the surface. The injection then places the PLLA upon withdrawal, usually in amounts of 0.1-0.2 cc per pass. In the temple and above the malar ridge it is injected in submuscular, small depot-like deposits of 0.05 ml. A fanning pattern of injection has been recommended by some, however, a single entry point for multiple passes increases the chance of too much material being deposited in a single area, leading to nodule formation. In the subocular hollow, a successful technique for those comfortable injecting in the periorbital region is a reverse threading injection of small amounts (0.05-0.1 ml) beneath the orbicularis oculi and along the periosteum of the orbital rim.

Vigorous massage for 5 minutes to all injected areas immediately post-injection is important to assure proper dispersion in order to optimize results and avoid nodule formation. Patients should be instructed to massage daily for 1 week post treatment. The application of cold packs post injection is useful to limit bruising. Most patients require one vial per treatment session, and some, especially with significant lipoatrophy, require two vials. Injection sessions should be scheduled 4-6 weeks apart so that adequate time elapses to see volume enhancement. Three treatment sessions are often required to reach full correction.

Poly-1-lactic acid (PLLA), a.k.a. Sculptra, was approved by FDA in 2004 for the treatment of AIDS-mediated facial lipoatrophy. It’s inserted by injection into the subcutaneous tissue and triggers skin cell replication. A number of injections are necessary, but the aesthetic results for sunken cheek have been formidable. In the Europe-based studies, the effect persisted for 18-24 months. Aesthetic use of this substance is considered off-label, but has been utilized for pan facial augmentation. It’s very important to insert this product into the right level. Injection into the dermis could increase the chance of granulomas.

Here’s how PLLA works.

Facial fat atrophy may cause significant alteration in appearances and may be due to hereditary syndromes, disease or aging. In natural ageing, it happens in the form of loss of elasticity, degradation of collagen and reabsorption of bone. This sinking due to volume loss results in further skin redundancy.

A few degrees of lipoatrophy based upon anatomic considerations have been detailed. Trying to rectify by tightening without addressing volume replacement causes a skeletonized look. Volume replenishment has been attempted by various naturally-found (fat, collagen, hyaluronic acid) and man-made (acrylates, silicone and other polymers) fillers, both biodegradable (that is the body can break them down) and imperishable. Poly-L-lactic acid (PLLA), marketed in US and Europe as Sculptra, is a new type of fibroblastic fillers whose ‘volumizing effect’ is dependant on host response.

Injectable Poly-L-lactic acid, also known as Sculptra, is a biocompatible, reabsorbable material that kickstarts an intended foreign body inflammatory response, regeneration of skin cells and a slow metabolic degradation of the polymer microspheres. Histological and clinical data allude to long-lasting effects, that may last for longer than 2 years. Currently, Sculptra is FDA-approved solely for the indication of AIDS-mediated lipoatrophy, and esthetic usage are ‘off-label’, although randomised clinical studies for cosmetic usage are currently almost complete. Quite a few documentations summarise the biological effects and treatment of lipoatrophy with Sculptra.