How Sofwave tightens skin: parallel ultrasound heat at 1.5 mm

Sofwave is one of the skin tightening devices we use, and lately it is the one people ask about. The FDA cleared it to improve facial lines and wrinkles and to lift the brow. It is also cleared to lift lax tissue under the chin and on the neck (U.S. FDA 510(k) K240687; Wong 2023, PMID 37806683). Like Ultherapy, it uses ultrasound, but on a different principle. This article explains how it works, why the heat stays at 1.5 mm, and what to expect in results and recovery.

Parallel beams make cylinders of heat

Focused ultrasound devices such as Ultherapy heat one small point per pulse and lay those points down in rows. Sofwave sends several beams side by side at once, a method its maker calls Synchronous Ultrasound Parallel Beam, or SUPERB. Each beam forms a cylinder of heat 1.5 mm deep, in the middle of the dermis (Liao 2026, PMID 41985490). A cylinder heats far more tissue than a spot, so each pulse treats a larger volume. Untouched tissue remains between the cylinders, and that speeds recovery.

The skin rebuilds collagen and elastin

This controlled heat injury in the dermis sets off a healing response that builds new collagen and elastin. Collagen supports the skin, and elastin gives it elasticity. In skin samples taken after treatment, both fibers kept increasing for 10 months (Carruthers 2025, PMID 41405933). As the two rebuild together, fine lines soften and the skin firms up.

The heat stays at 1.5 mm

That depth does not change. Every cylinder forms at 1.5 mm, inside the dermis. Cooling built into the device protects the surface. The fat and nerves below the dermis do not reach the temperature at which tissue coagulates. Monopolar radiofrequency devices such as Thermage work differently, heating a broad volume from the dermis down to the fat (Suh 2020, PMID 32319176). Keeping the heat inside the target layer lowers the risk of surface damage and hollowed cheeks by design.

Most people go straight back to their day

Because the surface is protected, there is no visible wound, and the healthy tissue between the cylinders helps the treated spots heal. Right after treatment you can expect some redness and mild swelling that settle on their own. Most people return to their routine the same day (Liao 2026, PMID 41985490). The result itself builds gradually over the following months as new collagen and elastin form.

For help choosing between devices, see Ultherapy, Sofwave, or Thermage: which skin tightening treatment is right for you?.

References

1. U.S. Food and Drug Administration (2024). 510(k) Summary K240687: SofWave System. accessdata.fda.gov.
2. Wong A, et al. (2023). Ultrasound therapy for the skin. Facial Plast Surg Clin North Am. PMID 37806683 (opens in new window).
3. Liao D, et al. (2026). Use of ultrasound in face and neck rejuvenation. Facial Plast Surg. PMID 41985490 (opens in new window).
4. Carruthers J, et al. (2025). Synchronous parallel ultrasound induces long-term extracellular matrix remodeling of human skin. Dermatol Surg. PMID 41405933 (opens in new window).
5. Suh DH, et al. (2020). Monopolar radiofrequency treatment for facial laxity: histometric analysis. J Cosmet Dermatol. PMID 32319176 (opens in new window).