Dermal Fillers for Facial Harmony (eBook)

History of Fillers

The development of biocompatible and safe fillers required many years of study and research. Table 2-1 illustrates the historical evolution of fillers. With the development of local anesthesia and surgical techniques toward the end of the 19th century, more invasive cosmetic procedures became available, including soft tissue fillers. Fat was one of the first soft tissue fillers to be used after trauma and is still widely used today. However, autologous fat transplantation is considered a relatively major procedure, as it requires the transplantation of fat from another site, and its results may be variable. Prior to the introduction of autologous fat grafting, paraffin oil had been used for the restoration of volume and symmetry. However, its use was accompanied by a high incidence of inflammatory foreign body granulomatous nodules (paraffinomas), with consequent facial distortion and occasionally life-threatening pulmonary emboli. Hence, the use of paraffin oil was discontinued.3

Table 2-1 History of facial fillers

In the mid-20th century, a shift was seen toward purified synthetic polymers in the form of injectable silicone. Although seemingly promising at first, the US Food and Drug Administration (FDA) eventually banned this material because of its similar complications of granuloma formation.8 However, microdroplet injection of limited amounts of silicone material is still used today as an off-label use for silicone that is FDA approved for ocular injections.9–11 Teflon, a synthetic polytetrafluoroethylene polymer, was next tested as a soft tissue filler, but it was quickly abandoned because of the resultant inflammatory reaction and the difficulty of injection.12

The first facial filler to receive FDA approval was bovine collagen, under the trade name Zyderm (Inamed, now Allergan), in 1981. The approval of Zyderm led to widespread research and development of other fillers, including alloplastic and implantable materials, as well as a renewed interest in and use of autologous fat.13 Despite this added research, bovine collagen remained the only FDA-approved filler until 2003, when the FDA approved the first hyaluronic acid (HA) dermal filler, under the trade name Restylane (Galderma), for temporary soft tissue augmentation.14 Since then, numerous fillers have received FDA approval in response to the growing popularity of minimally invasive facial rejuvenation procedures5 (Table 2-2 and Box 2-1). Further investigations and research have continued, and more long-lasting synthetic fillers have become available, including calcium hydroxyapatite (CaHA) and poly-L-lactic acid (PLLA).15

Table 2-2 Injectable fillers listed by date of FDA approval

Products in boldface are currently available. The FDA is aware that unapproved versions of Juvéderm, such as Juvéderm Ultra 2, 3, and 4, are being sold and distributed in the US, including by online retailers. (Data from Kontis.8)

Box 2-1 FDA-approved indications for dermal fillers

Classification of Fillers

Dermal fillers can be classified according to their material properties, biodegradability, and duration of effect:

Material properties

• Autologous: Derived from the same individual (eg, autologous fibroblasts)

• Heterologous: Derived from a different species (eg, bovine collagen)

• Alloplastic: Nonbiologic material such as metal, ceramic, or plastic (eg, polymethyl methacrylate [PMMA])

Biodegradability

• Biodegradable: Capable of being broken down, especially into innocuous products (eg, HA, PLLA)

• Nonbiodegradable: Substance or chemical that cannot be changed to a natural state (eg, PMMA)

Duration of effect

• Temporary: Effective for less than 6 months (eg, collagen)

• Long-lasting: Effective for 6 to 24 months (eg, HA [12–24 months], CaHA [18–24 months])

• Semipermanent: Effective for 2 to 5 years (eg, PLLA [2–3 years])

• Permanent: Nonfading results (eg, PMMA)