Injectable Facial Fillers

20.1 Introduction

Now, more than ever, patients are enlisting the help of plastic surgeons to reduce the visible signs of aging. According to the American Society of Plastic Surgeons (ASPS), the number of cosmetic procedures performed in the USA has increased 393% from 1992 to 2002. This increase includes both surgical and nonsurgical procedures, and reflects worldwide trends.

The process of aging is quite complex and involves the following three important factors: global facial volume loss, dynamic and static wrinkles and folds caused by the repetitive movement of facial muscles, and laxity induced by the force of gravity. Generally, the process becomes apparent in the midto late 30s, when the eyelids droop, and wrinkles and fine lines appear around the eyes and mouth. As we age into our sixth decade of life, the wrinkling continues, the jaw line begins to sag, and the neck and nasal tip drop.

Traditionally, facial rejuvenation has focused on tightening skin through surgical resection and resurfacing. In recent years, however, a major shift in facial rejuvenation has occurred, with increasing emphasis on minimally invasive cosmetic improvement. Today, plastic surgeons can combat the effects of aging with a variety of non-incisional methods, primarily through the use of facial fillers. A multitude of soft-tissue fillers

D.W. Buck II ( ) and J.Y.S. Kim

Division of Plastic and Reconstructive Surgery, Northwestern University, Feinberg School of Medicine, 675 N. St. Clair Street, Galter 19-250, Chicago, IL 60611, USA

e-mail: dwbuck2@yahoo.com

M. Alam

Department of Dermatology, Northwestern University,

Feinberg School of Medicine, Chicago, IL, USA

exist today, each with their own recipe of chemical components, indications, and effectiveness. A thorough knowledge of the properties of these facial fillers is imperative for plastic surgeons treating patients with cosmetic complaints.

20.2 Historical Background

The search for the ideal facial filler began over a century ago, when Neuber [1] was first to describe autologous fat transfer for facial defects in 1893. Just a few years later, reports surfaced regarding the use of paraffin injections for cosmetic enhancement. This technique enjoyed considerable popularity until patients began to develop severe foreign body and granulomatous reactions. The use of liquid silicone for cosmetic purposes was popularized in Germany, Switzerland, and Japan in the 1940s. Beginning in the 1960s, it was also being used successfully in the USA. Despite its success as a soft-tissue filler, reports of significant complications and adverse events have precluded its approval for cosmetic purposes in the USA and Europe.

In the 1980s, the development and use of bovine collagen for cosmetic purposes welcomed a new era of soft-tissue augmentation. Over the past 5 years alone, the number of approved facial fillers in the USA and abroad has expanded rapidly. The most widely used dermal filler products fall into four broad categories: autologous fats, collagens, hyaluronic acids (HA), and biosynthetic polymers.

In addition to the categories based on their chemical makeup, facial fillers can be grouped according to their longevity or degree of permanence after injection. Non-permanent fillers are temporary, producing shortlived results and eventually undergoing resorption.