RESUMO
BACKGROUND: To date, no studies compared curative effects of thermal lesions in deep and superficial dermal layers in the same patient (face-split study). OBJECTIVE: To evaluate skin laxity effects of microneedle fractional radiofrequency induced thermal lesions in different dermal layers. METHODS AND MATERIALS: 13 patients underwent three sessions of a randomized face-split microneedle fractional radiofrequency system (MFRS) treatment of deep dermal and superficial dermal layer. Skin laxity changes were evaluated objectively (digital images, 2 independent experts) and subjectively (patients' satisfaction numerical rating). RESULTS: 12 of 13 subjects completed a course of 3 treatments and a 1-year follow-up. Improvement of nasolabial folds in deep dermal approach was significantly better than that in superficial approach at three months (P=.0002) and 12 months (P=.0057) follow-up. Effects on infraorbital rhytides were only slightly better (P=.3531). CONCLUSION: MFRS is an effective method to improve skin laxity. Thermal lesion approach seems to provide better outcomes when applied to deep dermal layers. It is necessary to consider the skin thickness of different facial regions when choosing the treatment depth.