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Background and objectives Recently, there have been several attempts to apply the laser therapy to hypertrophic scars (HTS). In particular, the fractional laser is in the spotlight for its usefulness in rapid wound healing and dermal remodeling. However, most previous studies have focused on the ablative fractional laser (AFL), and there are no studies on the mechanism of the nonablative fractional laser (NAFL) effect in HTS treatment. In this study, we aimed to evaluate the changes in histology and molecular chemistry to provide scientific evidence for the early treatment of HTS with NAFL. Study design/materials and methods A total of 40 hypertrophic burn scars were made on the abdomens of two female pigs. After epithelialization, the HTS were randomly subdivided into four groups-control, AFL, NAFL (low energy), and NAFL (high energy). Laser treatment was initiated 1 week after the crust fell and the epithelium became covered, and it was repeated for six sessions over an interval of 2 weeks. Five excisional biopsies were obtained for histologic analysis and biomarker assessment. Results Histologically, dermal remodeling with thin coil-shaped collagen fibers was observed in the NAFL groups. It also showed a significant increase of matrix metalloproteinase-2 (MMP-2) and Decorin at 16 weeks in an enzyme-linked immunosorbent assay. The reverse-transcription polymerase chain reaction analysis showed a tendency that high-pulse energy of NAFL led to higher messenger RNA expression than did the low-energy group. Conclusion The NAFL-treated groups showed characteristic collagen re-arrangement and a significant increase in MMP-2 and Decorin. These molecular changes suggest that MMP-2 and Decorin play a significant role in dermal remodeling. Early NAFL treatment for HTS could be supported with both histological and molecular evidence. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.

Background Facial palsy patients require reconstructive surgery because they suffer from an expressionless and deformed appearance especially during smiling. To gain a natural smile, various dynamic procedures rather than static procedures are performed. Through cadaveric studies with clinical implications on temporalis muscle and intraoral transposition, we were able to come up with a more effective and less invasive procedure than the conventional temporalis muscle transposition or lengthening temporalis myoplasty. The aim of this study is to describe our novel surgical technique for facial reanimation and evaluate its efficacy. Method Two intraoral incisions were made. Through the posterior incision, the tendinous portion of the temporalis was separated from the coronoid process and anterior border of the ramus. Through the anterior incision, submucosa tunneling was performed to fixate the temporalis tendon onto the new perioral site. Results 14 patients with facial palsy underwent intraoral temporalis transposition and their mouth corner excursion was measured for objective assessment after surgery. At resting state, mouth and cheek drooping was improved. At smiling, the excursion of the unaffected side was 10–17 mm. For the reconstructed side, 8 cases were considered excellent (exceeding 75% of normal side), 5 cases were considered good (exceeding 50%), and 1 case fair (exceeding 25%). Conclusion This temporalis transposition through the intraoral approach is a novel technique for facial reanimation reconstruction. It is s less invasive, immediately effective method with rapid recovery and minimal donor site morbidity without visible scar. Level of evidence IV.