Minimally and noninvasive skin tightening has become one of the most requested cosmetic procedures. Skin laxity often is apparent in areas of the face, neck, jawline, hands, abdomen, and thighs, with features of fine lines, wrinkles, and cellulite. Intrinsic and extrinsic factors contribute to the development of skin laxity. Intrinsic aspects include chronological age, stress, and genetics, whereas extrinsic influences include exposure to solar radiation, environmental toxins, and smoking.1,2 These factors affect the production and maintenance of both collagen and elastic proteins, which are the main components that help the skin stay firm and smooth. With a goal of improving skin laxity, multiple skin tightening modalities have been developed.
Traditionally, skin laxity was treated by invasive surgical skin procedures (eg, rhytidectomy), which carry a high financial cost, require an operating room and general anesthesia, have a prolonged recovery time with notable postoperative care, and have possible risk of unwanted scars.3,4 The risks associated with invasive procedures have spurned a growing demand for minimally invasive and noninvasive methods, which have fostered the development of several skin laxity reversal modalities over the last decade. Although the achieved results of these technologies are less dramatic and require more treatments, they do not possess the associated risks and adverse effects seen in invasive surgical procedures. As such, demand for these techniques has been growing among cosmetic patients.
There are multiple technologies that currently are employed to achieve noninvasive skin tightening. Laser therapy, radiofrequency (RF), ultrasound, and intense pulsed light (IPL) are methods that focus targeted energy to elevate temperatures in the deeper layers of the skin. Elevated thermal energy causes denaturing of collagen with preservation of heat-stable intermolecular cross-links. Skin tightening is achieved through physical shortening of the collagen fibers with preservation of the heat-stable intermolecular hydrogen bonds, which leads to an increase in the rubber elastic properties of the collagen polymer and stimulation of new collagen formation.5,6 The temperature at which this process occurs has been frequently reported as approximately 65°C.7,8 Alternative noninvasive therapies that do not focus on elevated thermal energy for skin tightening include chemical peels and skin care products.
Given the multitude of treatment methods that have been developed to counteract skin laxity, this article seeks to provide an overview of some technologies, devices, and commonly used therapies to help dermatologists choose the appropriate modalities for their cosmetic patients.
Since its approval in the 1980s, laser therapy has become an alternative to invasive surgical skin tightening.9 Laser therapy utilized for treatment can be subcategorized into 2 types: ablative and nonablative.
Traditional ablative skin tightening utilized CO2 or erbium:YAG lasers. These lasers caused skin tightening by first ablating the epidermis cleanly off the dermis, with a partially coagulated area in the dermis, which triggered a wound-healing cascade followed by neocollagenesis and remodeling.10,11 Although this treatment displays notable retightening of the skin, traditional ablative lasers are not routinely used, likely because of lengthy recovery periods, risk for scar development, flares of acne and herpes simplex virus, hyperpigmentation, and delayed-onset hypopigmentation.9,12,13
Fractional ablative laser treatments soon emerged as an effective alternative to traditional ablative lasers. Various studies have noted better recovery times and side-effect profiles.14-18 This improvement is believed to be due to the method of wound healing in fractional ablative laser treatments. Ablative fractional photothermolysis works by generating deeply narrow focal ablations that involve the dermis and epidermis while leaving the surrounding skin unscathed, which allows for rapid re-epithelization, filling in of the dermal pockets, and stimulation of dermal remodeling.10,11,18,19 Studies have demonstrated a range of improvement in skin laxity from 56% to 65.3% at 6 months posttreatment.20,21 Although the incidence of reported side effects is better than with the traditional ablative laser, fractional ablative lasers have documented reports of similar types of side effects as traditional lasers due in part to ablation of the skin.22,23