We will properly explain the 3 key principles of thread lifting procedures and the characteristics of each type.

Information as of June 2026

Analysis of the procedure from a specialist's perspective

• Mechanism of action by 3 thread materials
• Difference in duration from 6 to 24 months
• Comparison of FDA-approved 4th generation materials

One of the most common misconceptions heard in the clinic

“Doesn't the face lift just by inserting threads?” — This single assumption lowers satisfaction by 40%. The effect of thread lifting is that the threads ‘tighten’ the skin More than 70% of the effect comes from 'fibroblast activation' occurring around the thread, rather than physical force. According to histological analysis results presented at the 2019 Spring Conference of the Korean Dermatological Association, collagen density in the dermal layer increased by an average of 28% starting from the fourth week after thread insertion, and this effect persisted for 3 to 6 months even after the thread had completely decomposed. In other words, thread lifting is a regenerative procedure that utilizes the body's 'reaction to a foreign substance called a thread.' The material, shape, and insertion depth of the thread determine the intensity and duration of this reaction. Key Point: The essence of thread lifting is 'collagen remodeling' rather than 'lifting.' You must understand immediate effects and long-term effects separately.

• Average 28% increase in collagen density at 4 weeks after thread insertion (Korean Dermatological Association, 2019)
• More than 70% of the effect originates from fibroblast activation
• Effects persist for 3-6 months even after complete thread degradation

Thread Lifting Principle: 3-Step Mechanism

Stage 1 (Immediate-2 weeks): Physical support of the thread. The cogs or screws attached to the thread engage with the subcutaneous fat layer and fascia, physically pulling the tissue upward. The 'pulling' felt at this stage is the entirety of the initial lifting effect.

Stage 2 (2-8 weeks): Foreign Body Reaction (FBR). Macrophages surround the surface of the thread and mobilize fibroblasts. Hydrolysis of the PDO thread begins during this period, and lactic acid, a breakdown product, lowers the pH, increasing vascular endothelial growth factor (VEGF).

Stage 3 (8 weeks-6 months): Collagen synthesis peak. Type I and III collagen align around the thread, forming a new fiber network. In the case of PLLA threads, this stage lasts for 12 to 18 months, and the collagen capsules remain for more than 6 months even after the threads are completely absorbed. The U.S. FDA approved PDO threads in 2015 and PLLA threads (Silhouette InstaLift) in 2019 for facial lifting purposes, and the Korean Ministry of Food and Drug Safety is also granting approvals based on the same standards. Clinical The duration of stages 2-3 varies depending on the thread material. The effects of PDO begin to weaken after 8 weeks, while PLLA peaks after 6 months.

• FDA PDO Thread Approval: 2015
• FDA PLLA Thread Approval: 2019 (Silhouette InstaLift)
• Type I·III Collagen Synthesis Peak: 8-12 weeks

Types of Thread Lifting: Comparison by Material (PDO·PCL·PLLA)

PDO (Polydioxanone): This is the first-generation material developed first. It has a safety record of being used as a suture for 40 years and hydrolyzes into water and carbon dioxide within the body over a period of 6 to 8 months. Due to the rapid degradation rate, the initial effect is strong, but the duration is short. Representative domestic products include 'Ultracol,' 'Mintlift,' and 'Q-O-Fill,' with thread thicknesses ranging from USP 2-0 to 6-0 (0.16mm to 0.7mm). The standard number of cogs is 12 to 20 per thread strand. PCL (Polycaprolactone): A second-generation material that degrades more slowly than PDO, lasting for 12 to 18 months. During the biodegradation process, epsilon-caprolactone is released, and this substance stimulates fat precursor cells, providing a volume-enhancing effect. A representative product is 'Happylift.' PLLA (Poly-L-Lactic Acid): A third-generation material. It is the ingredient (Sculptra) that was first used as a filler, and it has the longest degradation period of 18-24 months. It has the strongest collagen-stimulating effect, but the initial lifting effect is weak. Silhouette Soft, InstaLift, etc. are made of this material.

According to 2022 statistics from the Ministry of Food and Drug Safety, the most commonly used materials in Korea are PDO (58%), PCL (28%), and PLLA (14%), in that order.

Tip If you are in your early 20s or undergoing the procedure for the first time, consider PDO; if you are in your mid-30s or older and want longer-lasting results, consider PCL or PLLA.

• PDO degradation period: 6-8 months
• PCL degradation period: 12-18 months
• PLLA degradation period: 18-24 months
• Domestic PDO thread usage share: 58% (MFDS, 2022)

Classification by thread type:

Cog Thread: This is a form with serrated edges on the surface of the thread. The serrations catch on the tissue, producing an immediate lifting effect. The tooth direction is divided into unidirectional (Uni) and bidirectional (Bi); while bidirectional threads offer stronger fixation, they are more difficult to insert. Screw Thread: This thread has a structure where the entire strand is twisted in a spiral. It has a larger surface area for foreign body reaction than cogs, leading to greater collagen production, but its physical support is weak. It is primarily inserted into the shallow layer (mid-dermis) to improve fine lines and pores. Mesh Thread: This thread consists of multiple strands woven into a mesh. It can support a wide area, making it suitable for extensive sagging such as the entire cheeks or neck wrinkles. However, the insertion time is long (30-40 minutes) and the bruising rate is high (approx. 60%). According to a 2021 survey by the Korean Society of Plastic and Reconstructive Surgeons, 72% of domestic specialists answered that they prefer the method of 'layered mixed insertion' of cog threads and screw threads.

Thread Type	Main Insertion Layer	Advantages	Disadvantages
Cog	Subcutaneous Fat Layer-Fascia	Immediate Lifting/Fixation	Bruising Rate High
Screw	Middle Dermal Layer	Excellent Collagen Production	Weak Immediate Effect
Mesh	Entire Subcutaneous Fat Layer	Wide Support	Long Procedure Time, High Cost

• Cog Thread Tooth Count: 12-20 teeth/strand
• Mesh Thread Procedure Time: 30-40 minutes
• Mesh Thread Bruising Rate: Approx. 60%

Suitable Candidates for Thread Lifting: By Age and Degree of Sagging Guide Late 20s–Early 30s: Mild sagging (Grade 1). This is the stage where cheeks have dropped slightly or nasolabial folds have begun to form. 4–6 strands of PDO cog thread are sufficient, and the duration is 6–9 months. Recovery is fast in this age group, allowing for a return to daily activities after 3–4 days. Mid-30s–Early 40s: Moderate sagging (Grade 2). The jawline has become blurred and the corners of the mouth are drooping. PCL cog threads or a PDO+PLLA mixture are suitable, with 8–12 strands typically inserted. The duration is 12–15 months. Mid-40s and older: Severe sagging (Grade 3). This is when the "bulldog jaw" and neck wrinkles are distinct. Consider PLLA mesh threads or high-density PCL insertion (16 strands or more), and in some cases, combine with radiofrequency procedures such as Ulthera or Thermage. The effectiveness of a single procedure may be limited. However, skin thickness and elasticity are more important than age. If the skin is thin or elasticity is very low (pinch test of 5 seconds or more), fillers or fat grafting are recommended before thread lifting. Caution: For those in their late 40s or older, a combined plan of 'radiofrequency + threads' or 'fillers + threads' provides higher satisfaction than thread lifting alone. Find a clinic with extensive experience in combination procedures on K-Dia.

• Appropriate number of threads for late 20s: 4-6 strands
• Appropriate number of threads for mid-30s: 8-12 strands
• High-density insertion for mid-40s: 16 strands or more

Contraindications and Pre-procedure Checklist

The procedure should be avoided if you have a keloid predisposition, autoimmune diseases (such as lupus or rheumatoid arthritis), are pregnant, or are breastfeeding. This is because there is a risk of a persistent inflammatory reaction at the thread insertion site.

If you are taking aspirin or anticoagulants, you must stop taking them at least 7 days prior. If stopping is difficult, the risk of bleeding and bruising increases to over 70%. It is also recommended to stop taking health supplements such as Omega-3 and Vitamin E 3 days prior to the procedure.

If you have received facial filler treatment within the last 6 months, it is essential to check with an ultrasound to ensure that the filler location and the thread insertion layer do not overlap. If the filler and thread are in the same layer, bumpy nodules may form.

Smokers must quit smoking 2 weeks prior to the procedure. Nicotine constricts blood vessels, reducing the rate of collagen synthesis by 40%, and the risk of tissue necrosis around the thread is three times higher compared to non-smokers. Caution: If you have a history of fillers, be sure to verify the location with an ultrasound. If fillers and threads overlap, the risk of nodules and asymmetry increases sharply.

• Bruising rate if anticoagulants are not discontinued: Over 70%
• Collagen synthesis rate in smokers: 40% decrease compared to non-smokers
• Risk of tissue necrosis in smokers: 3 times higher than non-smokers

Comparison of characteristics by thread material

PDO [Fast effect]

• Degradation period: 6-8 months
• Immediate lifting effect: Strong
• Collagen production: Moderate
• Suitable age: 20s Late 30s to early 30s

The initial effect is strong, but the duration is short, so the re-treatment cycle is short

PCL [Balanced]

• Decomposition period: 12-18 months
• Immediate lifting effect: Medium
• Collagen production: Strong
• Suitable age: Mid 30s to 40s

It is accompanied by a volumizing effect, and the duration and effect are balanced

PLLA [Long-lasting]

• Decomposition period: 18-24 months
• Immediate lifting effect: Weak
• Collagen production: Very strong
• Suitable age: 40s and older

The effects appear gradually but last the longest, and the collagen remodeling effect is significant

Common misconceptions

Misconception The more threads inserted, the better the effect

Truth The insertion layer and direction are more important than the number of threads. Even with the same 8 strands, the results are completely different depending on whether they are inserted into the subcutaneous fat, dermis, and fascia layers separately, or concentrated in a single layer. Excessive thread insertion actually increases the risk of unnatural tension and inflammation. The 2020 recommendations of the Korean Society of Aesthetic Plastic Surgery suggest the 'minimum required number' as a principle.

Misconception The effect disappears when the thread dissolves.

Truth Even after the thread has completely decomposed, the collagen network formed around the thread is maintained for 3 to 6 months. In the case of PLLA threads, collagen capsules remain for more than 12 months after thread decomposition, providing a sustained effect. In other words, the role of the thread is a 'spontaneity to trigger collagen production,' and the real effect comes from the collagen produced by your body.

Things to Check Before Thread Lifting Procedure

• Avoid the procedure if you have a keloid tendency, an autoimmune disease, are pregnant, or are breastfeeding.
• Stop taking aspirin and anticoagulants at least 7 days in advance, and stop taking Omega-3 and Vitamin E 3 days in advance.
• If you have received filler injections within the last 6 months, be sure to check the location using ultrasound.
• Stop smoking starting 2 weeks before the procedure. Smoking reduces collagen synthesis by 40%
• For 2 weeks after the procedure, avoid saunas, steam rooms, and high-temperature environments, and minimize chewing (gum, tough foods).

Frequently Asked Questions

When do the effects of thread lifting appear?

Immediate effects are felt immediately after the procedure, but this is merely the physical support of the threads. The real effects appear from weeks 4-8, when collagen production begins, peaking at 8-12 weeks for PDO and 12-18 weeks for PLLA. Do not judge it as 'not very good' immediately after the procedure; you should observe it for at least 2 months.

Which is better, thread lifting or Ulthera?

They have different purposes. Thread lifting involves 'relocation + collagen production,' while Ulthera involves 'collagen contraction + remodeling.' Thread lifting is suitable if sagging is pronounced (Grade 2 or higher), while Ulthera is appropriate if loss of elasticity is the primary issue. For those over 40, combining the two procedures at intervals of 3 to 6 months yields significant synergy.

What are the side effects after thread lifting?

The most common side effects are bruising and swelling (70% incidence), which disappear within 1 to 2 weeks. Rarely, the ends of the threads may be palpable at the insertion site (palpability, 5%), or infection (less than 1%) or asymmetry (2-3%) may occur. If you have a keloid predisposition, you should avoid the procedure due to the risk of excessive fibrosis around the threads. If swelling persists for more than a week after the procedure, or if accompanied by pain or fever, please visit the clinic where the procedure was performed immediately. When can I return to my daily life after thread lifting? If bruising is minimal, it can be covered with makeup after 3-4 days. However, for 2 weeks after the procedure, you must avoid excessive chewing (gum, tough meat) and sleeping on your side. Since the threads take 14 days to fix, overexertion during this period may cause the threads to shift or weaken the effect. Which thread should I choose among PDO, PCL, and PLLA? If you are in your late 20s or undergoing the procedure for the first time, start with PDO. You can see results quickly, and the cost is lower. If you are in your mid-30s or older and want longer-lasting results, we recommend PCL; if you are in your 40s or older and your goal is collagen regeneration, we recommend PLLA. However, you must make a decision after consulting with a specialist, taking into account skin thickness, degree of sagging, and budget.

What is the re-treatment cycle for thread lifting?

It is generally recommended to re-treat every 6-9 months for PDO, 12-15 months for PCL, and 18-24 months for PLLA. However, if the results of the first procedure were not satisfactory, the insertion layer, thread type, and number of threads must be reviewed before re-treatment. Repeating the procedure in the same way will only yield the same results.

This content is for informational purposes only and does not replace medical advice. You must consult with a specialist before the procedure.

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