SAN DIEGO – The use of threads to improve skin laxity is making a comeback, thanks largely to advances in absorbable sutures.
“Thread lifts were popularized in the 1990s, but I think they were misrepresented as an alternative to a surgical face-lift, which remains the gold standard,”, said at the annual Masters of Aesthetics Symposium. “A thread lift is certainly not like a traditional face-lift; it’s much more subtle.”
In the 1990s, clinicians used nonabsorbable sutures for thread lifts, including polypropylene-barbed threads, which caused adverse events ranging from extrusion and migration to thread expulsion, dimpling, granuloma formation, and prolonged pain. As a result, the Food and Drug Administration withdrew its approval of contour thread aesthetic procedures in 2009. Since then, the development of absorbable threads made from polydioxanone (PDO) and poly-l-lactic acid (PLLA) has led to renewed interest in thread-lift procedures, yet the long-term effects remain unclear.
“There are some nice benefits to thread lifts,” said Dr. Ortiz, who is director of laser and cosmetic dermatology at the University of California, San Diego. “You get immediate results, which is always nice for patients, but with tissue tightening using energy-based devices, results are unpredictable and it can take 6 months to see the results. With resorbable sutures, we’re seeing fewer complications, and the amount of lifting is more predictable because you’re physically lifting the tissue. In some cases, threads are able to lift tissue more than energy-based devices. There is minimal recovery, it requires local anesthesia, and it’s less expensive than a surgical face-lift, which can run $10,000-$15,000 or more.”
For skin lifting, clinicians implant threads subcutaneously. When tugged in the opposite direction, the barbs anchor in adipose tissue, increasing tensile strength while suspended in the dermis and overlying tissue. This produces a fibrous adhesion capsule that helps to solidify anchorage of the suture long term. Fibrosis has been shown to increase local collagen production. PDO and PLLA are known collagen stimulants and are postulated to stimulate a long-term benefit in rejuvenation, Dr. Ortiz said, but overall evidence regarding their use in thread lifts is weak.
“Existing studies have a very short follow-up period and there is really no standardized protocol, so we don’t know really know a lot about them yet,” she said. Lana Tong, MD, and Evan A. Rieder, MD, of New York University recently published a systematic review of the literature on the topic ().
PDO is biodegradable by hydrolysis over 4-8 months and is used as absorbable suture material for prolonged tension–bearing areas. “It causes neocollagenesis with a foreign-body reaction,” Dr. Ortiz said. Meanwhile, PLLA is a collagen stimulator used for prolonged volume restoration. “It’s used an aesthetic filler, but a known complication with PLLA injections is the formation of subcutaneous nodules and late onset granulomas,” she said.
Early in 2019, Korean researchers published results of a study that set out to evaluate the collagen-producing effects of powdered PDO injection, compared with PLLA injection, in a murine model (). “It showed both PDO and PLLA induced granulomatous reactions and collagen formation, but this decreased at 12 weeks,” said Dr. Ortiz, who was not involved with the work. “PDO had slightly more collagen formation than PLLA.”
Indications for thread lifts, she continued, are for jawline lift, cheek enhancement, brow lift, wrinkle reduction, body contouring, acne scarring, and texturing. “Choose patients with good skin quality: not too thick/heavy, and not too thin. Patients with moderate skin sagging are going to better candidates than those with severe skin sagging.”
One type of absorbable suspension suture, the Silhouette InstaLift, is made of polyglycolide/l-lactide and is FDA cleared for temporary midface suspension targeting the elevation of cheek laxity. “It is a bidirectional implant with four, six, or eight cones per side,” Dr. Ortiz said. “They provide immediate suspension of the tissue until collagen production ensues. These tend to last a year or 2, but there are no controlled studies to confirm that. I’ve found that if you’re able to lift tissue in an upward direction rather than posteriorly you get a better result, but you’re limited by the length of these sutures. They’re not as customizable as some of the shorter sutures.”
In terms of adverse events following thread lift procedures, patients usually feel tender for about a week or 2. “They can have some bruising, mostly from the anesthesia,” she said.
To prevent temporary dimpling, Dr. Ortiz undermines with an 18-gauge needle and inserts perpendicular to the skin surface. “Extrusions can still occur,” she said. To prevent this, she pulls on the end and makes sure it’s buried subcutaneously.
Dr. Ortiz reported having financial relationships with numerous pharmaceutical and device companies, though none related to the content of her presentation. She is also cochair of the Masters of Aesthetics symposium.