INTRODUCTION
Visible signs of facial aging are the result of several
dynamic physiologic processes including dermal atrophy,
loss of facial fat, collagen breakdown, and loss
of bone.1-3 Dermal injectable products have become important
alternatives to traditional surgical procedures for the correction
of facial rhytides and the restoration of facial volume. The
popularity of these products has grown accordingly, with nearly
5 million cosmetic procedures involving injectable products
performed in the United States in 2012.4 Many of the aesthetic
goals traditionally associated with costly cosmetic procedures
can now be achieved for a fraction of the cost. A facelift can cost
more than $6,000, eyelid surgery close to $2,700, and cheek
implants nearly $3,000, according to The American Society for
Aesthetic Plastic Surgery (ASAPS), whereas cost of cosmetic
procedures involving injectable products ranges from $550-
$941 (National Average).4 We can provide patients with a more
global approach to facial rejuvenation focusing on re-volumizing
the face. Results can last for several years depending on
treatment, and most patients can return to their daily routines
immediately after treatment. Ultimately, the patient will determine
cost-effectiveness through discussions with their physician
before undergoing appropriate treatment.
Currently there are a variety of injectable treatments available
to restore the youthful appearance of the face by replacing lost
tissue volume, as well as filling and effacing rhytides and deep
folds. Due to complementary modes of action, biodegradable
volume augmentation products such as hyaluronic acid (HA),
calcium hydroxylapatite (CaHA), and poly-L-lactic acid (PLLA) are often used in combination with one another and with neurotoxins.
3,5 This allows for targeting specific effects of aging in
different anatomical regions of the face. Injectable PLLA is a
volume restoration product that contains biocompatible, biodegradable
microparticles of PLLA, which stimulate the production
of type 1 collagen, providing gradual volume.6,7 HA–based fillers
function primarily by attracting and binding water molecules
to create immediate volume.8 A biocompatible mixture of an
aqueous gel containing synthetic CaHA microparticles provides
immediate volume and serves as a matrix for the development
of new tissue via neocollagenesis.9,10 The neurotoxin botulinum
toxin type A temporarily denervates and relaxes muscles, resulting
in a reduction of furrows and lines.11-13
Considerations regarding the use of volume augmentation
products include rheologic properties, lifting capacity, and migratory
ability of the product.14 Injectable volume restoration
products are offered with a range of rheologic properties and
those with a high degree of firmness (G’), elasticity, and viscosity
may be best utilized in treating the nasolabial folds and
midface/lower face by creating lift and volume and resisting
post-injection spreading; whereas the use of less-firm and lessviscous
products may be better for treating more shallow folds
and lines.15,16 HA products are available in small gel particle
(SGP-HA) and large gel particle (LGP-HA) sizes; SGP-HA is indicated
for submucosal implantation for lip augmentation.17-20 The
primary author routinely dilutes SGP-HA 1:1 with 1% lidocaine
to decrease the viscosity, allow for better spread/flow, and possibly
decrease the potential for the Tyndall effect.
