Catherine DeGoursac discusses how you can use threads to create a mini-lift effect  without the need for more
invasive procedures

In the face of growing demand for non‑surgical techniques in aesthetic medicine, the implantation of tensor threads under the skin is increasingly performed to reposition slightly sagging areas in the face, the neck,  or certain parts of the body. Suspension threads of biocompatible materials are either resorbable or permanent. Both options aim to correct the moderate ptosis of tissue with an outpatient procedure under simple, local anesthesia, with very little risk when performed by expert hands, and with no or very little social exclusion. What makes this procedure truly unique is the nature of the material being implanted.

For several years, doctors preferred the use of non-resorbable threads made of polypropylene that remained in the dermal tissue of the patient. Their implant required small interventional skin procedures. In hindsight, the idea behind this technique was to produce long-term results and offer the possibility of re-tensioning the threads to obtain a new lifting effect without having to implant new threads (The Easylift® concept)¹. However, some medical reports indicated cases of early recurrences and complications after their use, such as protrusions of the threads, numbness, and foreign body granulomas^2,3,4,5.

In recent years, we have seen the emergence of tensor threads made of biomaterials that are fully absorbed once they have played their regenerating and tensioning role. The reversible nature of their action is a guarantee of security for the patient. This very promising medical breakthrough, presented as an alternative to a light surgical facelift has stirred controversy within the medical community of aesthetic surgery. The aim of this article is not to provide an overview on the uses of resorbable tensor threads, but  try to explain the reasons for the current enthusiasm for the new generation of devices, which is also the author’s preferred choice.

Resorbable tensor threads
Implantable biomaterials

The most recent threads available to physicians are tensor threads made entirely of bioresorbable materials. These threads belong to the injectable medical devices category granted a CE medical marking certification.

There are essentially two types: threads made of polydioxanone (PDO) and those consisting of  L-polylactic acid (LPA) as the main component. All these threads share the common characteristic of featuring small notches for the PDO type or cones for the LPA across their length, all being equally resorbable with a bi-directional orientation to ensure their immediate anchoring to the subcutaneous tissue.

PDO is a highly secure material that is used in general surgery for sutures as well as in cardiovascular procedures. It is naturally biodegraded by the body over a period of 6 to 8 months. The threads made of PDO have experienced an increase in popularity in aesthetic clinics and practices in South Korea over the past 4 years. The Koreans have succeeded in bringing this procedure into the limelight, while improving it each year⁶.

However, the threads made of LPA could be more interesting as they are resorbed after approximately 12 months and the treatment effect has a duration of up to 18 months.

Polylactic acid is a polymer derived from lactic acid that is not only highly biocompatible with the human body but also fully biodegradable, something that has proven its value in a variety of medical applications, such as suture threads in aesthetic surgery, fields like cardiac surgery (stents), or orthopedic (screws and pins) and have enjoyed several years of sufficient testing that demonstrate their safety. In aesthetic medicine, this injectable implant has been used for more than two decades to restore lost volume associated with ageing. It is the only product to receive a Marketing Authorization (MA) in France as a treatment for facial wasting, a common side-effect of HIV treatment and is covered by French health insurance under such circumstances.

Action mechanisms and evidence of effectiveness

The new generation of resorbable tensor threads (LPA or PDO) have two main properties:

• A mechanical lifting action on the sagging tissue. The ‘lift’ effect is immediate and natural by means of the thread’s notching action
• Once attached under the skin, these biomaterials of exogenous origin generate a physiological action from the body’s natural defense system, that is to say, a local inflammatory response to a foreign body. By being gradually and naturally reabsorbed through dissolution in biological fluids, the threads stimulate the production of procollagen molecules and the development of a reactive fibrosis around them, which perpetuates the results beyond their resorption.

Recent studies show that LPA and the PDO encourage the synthesis of collagen in the dermis and increase the proliferation of fibroblasts. Among these studies, the author will mention three in particular.

The first study focused on the implantation of LPA threads on two patients⁶. The biopsies were performed at 3, 6, and 9 months post-procedure, respectively. The observation under an optical microscope and polarized light after a specific coloring of collagens by picrosirius red staining showed the production of endogenous collagen, especially of type I and its persistence in situ 9 months after implantation. The study, presented during the Barcelona Convention in October 2015, demonstrated the inducer effect that encourages the synthesis of collagen, particularly of type I. More in-depth studies are currently under review before their publication.

The second study was published in 2014 by Savoia et al. The authors concluded that the tensor effect is potentiated by the fibrosis around the threads, on the basis of histological criteria and ultrasound in mode B⁷.

The third study, published by Dr Otto at the end of 2015, focused on 100% PDO threads. The histological data highlights a large number of fibroblasts around the threads and an increase of new collagen fibers⁸.

The implantation of resorbable tensor threads is still a fledgling procedure. Results need to be validated by more exhaustive studies, but for the first time they show that threads made of LPA are collagenous protein inducers. These wires in PLA have the ability to induce the production of type I collagen in the dermis during the process of resorption of the threads and cones. This is why the visible benefits of the treatment can be maintained for up to 18 months.

Objectives and applications

This technique is intended to correct the slight to moderate sagging skin of the face and body and to reposition volume without increasing it. It is predominantly intended to be used in very specific cases with both women and men in their forties, but can be used even earlier depending on the ageing of the face:

• The most frequent corrections are performed on the face and in the neck area to:
• Raise the entire length of sagging eyebrows in order to give them a younger look (different from botulinum toxin injections, which can only raise the point of the eyebrow)
• Lift the cheeks and cheekbones
• Mitigate jowls, nasolabial folds, or sagging in the neck
• Raise the upper lip, which begins to sag over the years
• Redefine the oval shape of the face.
• The implant of tensor threads is now a non-surgical solution used to treat moderate sagging skin on certain parts of the body. It is specially designed to:
• Restore the curvy line of slightly sagging buttocks
• Re-tension the skin of the neckline, the abdomen, the knees, and the inside region of the arms and thighs.
• It is also a procedure designed for patients who refuse any type of surgical facelift, are in need of very subtle results, or have a contraindication preventing surgery
• The implant of tensor threads could also be a softer alternative to a surgical facelift for men, who are becoming more conscious of their looks and the scarring result of surgery and the risk of hair transfer on the tragus can often be dissuasive.

Contraindications

There are some medical contraindications:

• Pregnancy and breast-feeding are temporary contraindications
• Sagging skin from a surgical procedure
• Taking anti-coagulant medication
• Skin infections on the area that needs to be treated
• Autoimmune diseases
• Allergy to the biomaterials of the threads
• Area previously injected by a non-resorbable product to prevent the emergence of granulomas.
• There are also contraindications related to the procedure itself. You need to be able to deny non-compatible candidates, such as patients who have unrealistic expectations with this technique in regards to the effectiveness of the surgery, but also due to:
• Skin that is too thin: causing visible or tangible threads
• Skin that is too thick and heavy: causing the result to be insufficient
• Skin that is too wrinkled: the threads will be ineffective
• Excess skin and fat.

All of these cases fall into the surgical correction category. In patients who want to go ahead regardless, the physician needs to inform them that the result will inevitably be incomplete.

Pre-intervention consultation

The initial consultation is critical in order to verify the feasibility of the procedure. This first consultation, conducted by a trained practitioner in this technique, allows you to inform the patient of the aesthetic nature of the procedure, to make sure that there are no medical contraindications and check that the patient is a valid candidate for the treatment. Once all these conditions are met, the patient is given a detailed quote, a clear consent form, as well as an information document relating to the procedure. The number of threads and the nature of implantable materials is determined by the practitioner based on the condition of each patient.

Course of treatment

The treatment is performed at an outpatient medical office with the strictest possible compliance with the rules of hygiene and asepsis. No preparation is necessary but it is not recommended to take any aspirin or anti-inflammatory drugs during the days preceding the procedure. For patient comfort, an anesthetic cream can be applied on the treated area an hour before the session and/or a local anesthetic can be injected at the entry and exit points of the threads at the beginning of the session. Using a thin needle or a small cannula, the doctor inserts the threads under the skin, one by one, following a specific marking of the area to treat what would have been previously marked with a dermographic pencil. The thread is then anchored on the dermis by exerting a slight manual upward pull. The procedure should take 30 to 60 minutes depending on the type and the number of threads to implant and other indications. Several areas can be treated at the same time.

After the procedure, the patients are instructed to follow a certain number of recommendations provided by the doctor in order to not compromise the outcome: to rest, to limit any excessive facial expressions and any over-exertion, to avoid any strenuous physical activity, to not go inside a sauna or steam room, and to avoid any facial massage. This new therapeutic option offers many advantages, which includes an outpatient procedure under simple local anesthesia without an incision, none or very little social limitation, and treatment can be repeated as many times as desired since the materials are fully resorbable and can be supplemented by other rejuvenating procedures, such as the injection of fillers or botulinum toxin products.

Reactions

Any medical procedure, however small, involves a certain number of risks. The usual reactions are generally quite trivial. A few transitional and local reactions are nevertheless possible: bruises, slight edema, erythema (reddening), sensation of skin tightness on the treated areas, small skin folds in front of the ear and a slight asymmetry post-procedure.

Results

They occur in two distinct phases. The first is observed from an immediate lifting effect in the tension of the skin, with a gradual loosening the week following the procedure. The second, which leads to the synthesis of collagen around the thread, is more progressive. The threads will be fully resorbed after a few months (usually within 6 months to 1 year), but the aesthetic benefits are more durable due to the fibrosis around them (closer to 12 to 18 months). This treatment is therefore temporary and must be renewed to maintain the result, as per the patient requests.

The therapeutic success is greatly dependent on the technique and the treatment protocol developed by the doctor and the specificity of each case. Many factors related to the patient can influence the results, such as the age, lifestyle (tobacco, sun exposure) and the quality of the skin.

The author reviewed the results of the implantation of 100% bioresorbable tensor threads after two years of observation. The author often combines the implantation of threads made of LPA (two on each side of the face) with thicker threads made of PDO (at no additional charge), during the same procedure to obtain the best possible results at the lowest price. The author’s results have been satisfactory in the treatment of moderate sagging of the cheeks, neck, lips, and eyebrows but also in drooping buttocks or the inside part of the arm. This is obviously very encouraging and leads the author to continue on this path.

Discussion

Compared to surgical facelifts that require a thorough general or local anesthesia, in addition to the risks, scarring, and convalescence period involved, minimally invasive methods have gained a lot of popularity due to the numerous benefits mentioned above. The best example being the dermal implantation of tensor threads to achieve a lifting effect. It was around the end of the 90s, that plastic surgeons Marlen and George Sulamanidze developed their famous Russian threads or Aptos® threads, which were notched threads made of non-resorbable polypropylene. These permanent threads have been used for several years now, mostly due to the sustainability of results. Sulamanidze et al., published good and immediate persistent results based on a large number of patients and a long testing period^9,10.

In 2010, Doctor Foumentèze presented at the EMMA convention (European Masters in aesthetic and anti-aging medicine) in Paris, a multi-centered retrospective study (from 5 physician members of the SOMEREF or Medical Society of Research and Expertise on Suspension Threads) on 110 patients that were monitored for two years. This study showed the effectiveness of permanent suspension threads as well as their safety (only one case of infection, not specifically related to the threads but the result of the penetration of a foreign body). However, this very interesting data has not been published to showcase this experiment. The authors have reported some complications after their application, such as a reaction to a foreign body evidenced by the recent publication of Yoo et al¹¹. However, these complications remain very rare with highly trained practitioners. Permanent threads have evolved in recent years and more modern threads made of elastic and flexible silicone and polyester with rounded notches are available today.

However, the correction of moderate ptosis without excess skin through the implementation of tensor threads made of a fully resorbable material has seen an impressive resurgence in medical aesthetics due to their increased safety. Their recent arrival on the market has generated a growing interest by a good number of fellow colleagues, but also criticism from some others. Indeed, today we have two clearly opposing views: on one hand, the followers of the resorbable thread, and on the other, the non-resorbable thread crowd¹². With such context, it seems of the utmost importance to clarify as much as possible the arguments that guided the author’s choices. The author’s preference leans toward the resorbable threads for the following reasons:

• The exclusive use of fully biodegradable materials ensures maximum safety for patients
  The restorability of a biomaterial or the ability to gradually and completely degrade in tissue is an important quality since no foreign body remains after a certain period of time. This effect limits the risks of the procedure and any eventual local reactions (from the introduction of any foreign body in the skin) are reversible since it disappears with the threads. On the other hand, biomaterials destined to fully degrade cannot provide long term aesthetic results. In order to perpetuate the results, the patient will have to repeat the procedure, if he/she wishes to do so. The relatively short duration of effect is compensated by the advantages in terms of patient safety. The rise in popularity of these threads is the source of a lot of excitement among many doctors, but created a measure of scepticism from some corners in regard to their biological action. However, recent studies provide objective evidence in favour of tissue induction, which reactivates the local production of type I collagen with LPA based threads.
• Suspension threads can be a source of discomfort or dissatisfaction for patients
  In these cases, the resorbable threads will eventually disappear. The removal of a permanent thread can only be done by a trained professional.
• The author does not perform small surgery procedures at their medical office
  The implantation of permanent threads requires a small operation on the skin, such as an incision, a suture or a small detachment of the scalp.

To conclude this discussion, the author believes that the choice between a resorbable thread or a non-resorbable one will mostly depend on the practitioner’s technique, personal experience, familiarity with the subject, and previous results. As far as the author is concerned, they do not implant non-resorbable threads for aesthetic purposes, even if the side-effects of permanent products remain very rare considering the number of patients treated. For all the above reasons, it seems reasonable to favour the use of bio-degradable materials, which, despite their relative short duration, provide satisfaction and safety to the patients. The implantation of resorbable tensor threads is a technique that is still relatively new in the field of aesthetics, and for the most part, still under evaluation and development. Only a limited number of practitioners have recently published their clinical trial results, and have shared their personal experience^7,13,14. Nevertheless, recent studies have demonstrated the local regeneration of collagen after implantation. These results are, as yet, insufficient and need to be validated by larger studies and sufficient observation.

Generally speaking, implantable medical devices for aesthetic purpose only, whether or not resorbable, still lack sufficiently reliable and objective scientific data.

Conclusion

In the past few years, we have seen the emergence of minimally invasive medical alternatives in the field of cosmetic surgery. Their principle is based on the implantation of intradermal non-resorbable tensor threads designed to correct the moderate sagging skin of the face, neck and body. If the implantation of permanent threads is a ‘well-known’ technique, considering the large number of studies and procedures, the rise of a new generation of fully resorbable tensor threads over the past two years is starting to appeal to more and more doctors and patients due to their many benefits. Indeed, the implantation of these threads in the dermis does not require any dermal incision, stiches, or any social limitation. Requiring a simple local anesthesia in a medical office, it allows the reposition of the drooping volumes without increasing them and moderately tightening the sagging skin during the same operation. The implanted biomaterials will be spontaneously resorbed over time once their job is done.

This is the reason the author decided to favour this technique due to its increased safety for patients. It is quite possible to prolong the result by renewing the procedure, at the request of the patient. This technological breakthrough has now proven itself as a way to enable local collagen synthesis.

Regardless of the implanted thread, achieving a good result is highly dependent on the practitioner. A good knowledge of the anatomy surrounding the treated area, a practitioner well-versed on the procedure (particularly with the permanent threads), and even more importantly, an adequate selection of patients, are all factors that will significantly influence the final result. Even if the effectiveness of resorbable tensor threads remains the subject of heated debate, these two techniques — the implantation of permanent or resorbable threads — should not be viewed as competing solutions but as a different proposition based on the personal opinion of the physician and the safety of the patient.

From the author’s point of view as an aesthetic doctor, tensor threads are not meant to replace the surgical facelift procedures that, even if they are more intensive and more invasive, remain irreplaceable when the damage of time is simply too severe.

Today, the implantation of resorbable tensor threads is the only temporary and reversible soft technique that gives you that natural ‘lift’ effect, provided that the procedure is done by a doctor who has mastered the art and after a strict selection of valid candidates.