Thermage is a non-invasive skin elasticity treatment that remodels collagen and induces neocollagenesis by delivering thermal energy to the dermis and subcutaneous fat layers using monopolar radiofrequency (RF) energy. Since its FDA approval in 2002, the technology has continuously evolved, with Thermage FLX (Fourth Generation) being the latest version currently in use. In particular, Thermage FLX, combined with the pre-heating technique performed at Vie Clinic, offers significantly improved treatment efficiency and patient convenience compared to previous versions. This article explains the scientific basis of Thermage FLX, from its physical mechanism of action to its clinical effects and a scientific comparison with similar energy-based devices.
1. The Core Cause of Decreased Skin Elasticity — Why Collagen is Important
Skin elasticity is primarily determined by collagen and elastin fibers that constitute the dermis. Collagen accounts for about 75-80% of the dry weight of the skin, with Type I collagen playing a key role in skin elasticity and structural support.
As aging progresses, the following changes occur in combination:
- Decreased collagen synthesis due to reduced fibroblast function
- Accelerated breakdown of existing collagen due to activation of matrix metalloproteinases (MMPs)
- Reduced structural flexibility due to abnormal cross-linking between collagen fibers
- Worsening skin sagging due to redistribution and volume loss of subcutaneous fat
UV exposure accelerates this process, with UVA in particular penetrating deep into the dermis and promoting collagen breakdown. Thermage FLX serves as a fundamental means of improving skin elasticity by reactivating the weakened collagen structure through thermal energy.
2. How Thermage FLX Works — The Physical Mechanism of Monopolar Radiofrequency
Thermage FLX delivers 6.78MHz monopolar radiofrequency (RF) energy to the skin. Unlike bipolar or multipolar systems, the monopolar method is characterized by uniform energy penetration from the skin surface to deeper layers towards the opposite electrode (grounding pad).
Heat Generation Mechanism:
When RF current vibrates ions (Na⁺, K⁺, Cl⁻) within the skin tissue, heat is generated due to the tissue's electrical impedance (Joule Heating). The heat generated is concentrated in the deep dermal layer (2-3mm) and subcutaneous fat layer (4-6mm), while the epidermis is continuously protected by a cryogen cooling system.
Two Stages of Collagen Response:
- Immediate Effect: The triple helix structure of collagen undergoes contraction (thermal denaturation) at approximately 60-70°C. Some patients experience an immediate tightening sensation after the procedure due to this contraction response.
- Long-term Effect: Heat-induced tissue damage triggers a wound healing response, activating fibroblasts to synthesize new collagen. This neocollagenesis occurs over 2-6 months post-treatment, with the peak effect often observed around 6 months after the procedure.
3. Clinical Significance of the Pre-Heating Technique
The pre-heating Thermage FLX applied at Vie Clinic goes beyond simply delivering energy; it involves sufficiently heating the skin tissue (pre-heating) before delivering the main treatment energy.
Scientific Basis of Pre-Heating:
- When tissue temperature is sufficiently elevated beforehand, the subsequent treatment energy acts more uniformly at the desired depth.
- It allows for a more stable reach of the threshold temperature (60-70°C) for collagen contraction, enhancing treatment efficiency.
- The energy penetration depth is optimized as the tissue's impedance decreases.
A study published in the Journal of Cosmetic and Laser Therapy in 2022 showed that the Thermage treatment group that applied the pre-heating protocol had significantly higher skin elasticity improvement scores compared to the standard protocol, with similar or lower patient pain scores.
4. Clinical Effects — Evidence from Studies
The clinical efficacy of Thermage has been validated through numerous peer-reviewed studies.
In a single-session clinical study by Fitzpatrick et al. (2003), 83% of patients who underwent Thermage on the face, neck, and around the eyes showed improvements in skin elasticity and wrinkles at the 6-month mark. This study has been widely cited as foundational data for subsequent clinical evidence of Thermage.
A study by Dover et al. (2007) reported that 86% of patients experienced sustained improvement 12 months after a single session of Thermage around the eyes (periorbital area), and histological examination confirmed an increase in neocollagen fibers in the dermis.
Recent studies on the 4th generation FLX version have reported improved treatment reproducibility and patient convenience compared to previous generations due to the incorporation of AccuREP™ technology (which measures changes in skin impedance in real-time during treatment to automatically adjust energy).
Duration of Effects:
Based on a single treatment, the neocollagenesis effect is reported to last up to 1-2 years, varying depending on individual aging rate, lifestyle, and sun protection habits. Long-term elasticity maintenance is possible through periodic retreatment (1-2 times per year).
5. Thermage FLX vs. Ultherapy (HIFU) vs. InMode (Bipolar RF) — Comparison of Energy Mechanisms
Vie Clinic offers various energy-based lifting devices, including Ultherapy Gold and InMode Lifting, in addition to Thermage FLX. Understanding the energy mechanism and suitable candidates for each device is crucial.
Thermage FLX (Monopolar RF):
- Energy Type: 6.78MHz radiofrequency current
- Depth of Action: Entire dermis + upper subcutaneous fat layer (2-6mm)
- Features: Strong in overall skin elasticity improvement due to heating of a wide volume. Effective for early to moderate skin sagging.
- Suitable Candidates: Decreased skin elasticity, sagging of the glabella, eye area, neck, and abdomen.
Ultherapy (HIFU):
- Energy Type: High-Intensity Focused Ultrasound (HIFU)
- Depth of Action: Precisely delivered to the SMAS layer (superficial musculoaponeurotic system) at a depth of 4.5mm.
- Features: Strong in structural lifting by directly delivering energy to the SMAS layer. Suitable for significant skin sagging.
- Suitable Candidates: Sagging cheeks, eye area, jawline, SMAS layer laxity.
InMode Lifting (Bipolar RF):
- Energy Type: Bipolar RF + Subdermal Laser (460nm)
- Depth of Action: Precisely adjustable from 2-8mm using subdermal fat layer penetrating needles.
- Features: Selective heating and remodeling of the subcutaneous fat layer. Simultaneous improvement of fat and elasticity.
- Suitable Candidates: Double chin, submental fat, sagging of the abdominal fat layer.
These three devices are not in competition but can be used complementarily. Establishing a treatment strategy, either alone or in combination, based on the layer and severity of skin sagging is the way to achieve optimal results.
6. Treatment Candidates and Precautions
Suitable Candidates for Thermage FLX:
- Early to moderate decrease in skin elasticity in individuals aged 30-early 60s.
- Onset of sagging in the eye area, forehead, cheeks, jawline, and neck.
- Can be combined with laser pigment treatments (on the same day or after a certain interval).
- For those who wish to return to daily activities without recovery time.
Precautions:
- Contraindicated for individuals with metallic implants (pacemakers, metal implants, etc.).
- Contraindicated during pregnancy.
- Cannot be directly applied to areas of skin infection or open wounds.
- Expected effects may be limited in cases of excessive skin sagging (requiring surgical correction).
- Temporary redness and swelling may occur post-treatment, usually resolving within a few hours to one day.
7. Checklist Before Considering Thermage FLX
Thermage FLX aims for "qualitative improvement of the skin structure itself" rather than "immediate dramatic changes." Thermage FLX is particularly effective in the following cases:
- When experiencing decreased elasticity but not yet requiring surgical intervention.
- When seeking to improve skin texture in conjunction with fillers or Botox.
- When maintaining daily life without downtime is important.
- For those desiring long-term, continuous skin health management.
Conversely, if the skin sagging is severe enough to warrant surgery (facelift), the effectiveness of energy-based procedures may be limited. It is most important to choose a treatment that suits your current skin condition and goals through a specialist's diagnosis.
8. Thermage FLX Treatment at Vie Clinic
At Vie Clinic, we apply a customized protocol that optimizes the energy absorption efficiency of skin tissue through pre-heating Thermage FLX.
- Personalized energy settings based on pre-treatment analysis of skin thickness and elasticity.
- Safe and uniform energy delivery through real-time impedance monitoring based on AccuREP™ technology.
- Possibility of planning combination treatments with other energy devices such as Ultherapy Gold and InMode Lifting.
- Proposal of an integrated anti-aging plan with petit procedures like fillers and Botox.
If you are concerned about decreased skin elasticity or are curious about the types and suitability of lifting procedures, please consult with a specialist at Vie Clinic.
