Abstract
BACKGROUND: Low-temperature dielectric-field heating has emerged as a non-ablative modality that selectively engages water-rich dermal and fibro-septal structures while sparing adipose tissue. Operating within a controlled thermal-shock window (∼42–45 °C), the Dermis Layer Targeted Dielectric Heating System (DLTD) —when utilized at low-to-moderate intensity levels—induces reversible collagen recoil and early dermal tightening without high-temperature injury. Although conceptually suited for mid- and lower-face rhytids, clinical data remain limited. OBJECTIVE: To evaluate the clinical efficacy, three-dimensional structural elevation, and safety of a single DLTD session, applied within a low-to-moderate energy range, for improving nasolabial folds and marionette lines in Asian women. METHODS: Thirty-two women aged 35–65 years with visible nasolabial folds and marionette lines received one DLTD session delivered at low-to-moderate intensity levels along the midface-to-lower-face axis. Outcomes were evaluated at baseline, immediately after treatment, and at weeks 4 and 8. Wrinkle severity was assessed using WSRS and the Merz scale, and structural changes were quantified by 3D vector analysis of midface elevation and marionette descent. GAIS ratings were obtained at week 8, and pain and adverse events were documented. RESULTS: WSRS improved from 3.1 to 2.0 (35.5%), and Merz scores from 2.6 to 1.9 (26.9%) at week 8. Three-dimensional analysis showed progressive vertical elevation and improved perioral support, with midface elevation increasing from +0.6 mm to +1.9 mm and marionette descent improving from −0.4 mm to −1.2 mm. At week 8, 95% of investigator and 92% of patient GAIS ratings indicated improvement. Pain was minimal (0.4/10), and no serious adverse events occurred. CONCLUSION: A single DLTD session at low-to-moderate intensity produced consistent wrinkle reduction, measurable three-dimensional structural elevation, and high satisfaction with negligible discomfort and no downtime. These findings support DLTD as a promising non-ablative option for mid- and lower-face rejuvenation. Larger controlled studies are needed to establish long-term durability and comparative efficacy.