Effects of radiofrequency on the healing of skin wounds in rats: analysis using digital planigraphy and histological evaluation / Efeitos da radiofrequência na cicatrização de feridas cutâneas em ratos: análise por planigrafia digital e avaliação histológica

Introduction: Given the extensive use of plastic surgery and the search for better aesthetic and functional results, it is necessary to research ways to improve healing and scarring. The objective is to evaluate the effects of three radiofrequency (RF) sessions in healing the skin of mice. Methods: Forty-eight rats were divided into four groups by day of sacrifice and treatment (RF group: RG; control group: CG). Dissection of the excisional wound of 2 cm x 2 cm (4 cm²) was performed and a 6-mm punch was used to hold two excisional wounds 0.6 cm in diameter. After 24 h, radiofrequency was performed using Spectra® directly on the wound in the dorsal region for 7 minutes at 38°C. This was repeated three times on alternate days. For the control group, the radiofrequency protocol was performed with the device switched off. Results: A larger area of the square wound was measured on postoperative day three in RG (RG7: 3.3 cm² ± 0.7 cm² vs. CG7: 2.4 cm² ± 0.4 cm²; p = 0.009). On day 14, the square wound in RG was greater than in CG (RG14: 1.9 cm² ± 0.5 cm² vs. CG14: 1.0 cm² ± 0.3 cm²; p = 0.001). There was a 90% closure of wounds in CG14. In RG14, 60% of the wounds were re-epithelized while 40% remained ulcerated. In CG7, 70% of the remaining wounds were ulcerated and 30% were re-epithelized. In RG7, 8% were re-epithelized and 92% remained ulcerated. Conclusion: Radiofrequency has a negative influence on the healing process, as indicated by mice that received radiofrequency having a persistent ulcerated wound.

Introdução: Tendo em vista o número de cirurgias plásticas e a busca por melhores resultados estético-funcionais fazem-se necessárias pesquisas para encontrar meios para melhorar a cicatrização e as cicatrizes. O objetivo é avaliar os efeitos de três sessões de radiofrequência na cicatrização da pele de ratos. Métodos: Quarenta e oito ratos machos foram divididos em quatro grupos conforme ao grupo que pertenciam e o dia do sacrifício (grupo radiofrequência - GR - e grupo controle - GC). Realizada a dissecação da ferida excisional de 2 cm x 2 cm (4 cm²) e utilizou-se um punch de 6 mm para a realização de duas feridas excisionais de 0,6 cm de diâmetro. Após 24 h, foi realizada a radiofrequência com o equipamento Spectra® na região dorsal, diretamente sobre as feridas por 7 minutos, com temperatura de 38ºC. Repetida por três vezes, em dias alternados. No grupo controle foi realizada com o aparelho desligado. Resultados: Foi encontrada área maior na ferida quadrada, no 3º dia pós-operatório do GR (GR7 3,3 cm² ± 0,7 cm² vs. GC7 2,4 cm² ± 0,4 cm², p = 0,009). No 14º dia a ferida quadrada do GR foi maior do que no GC (GR14 1,9 cm² ± 0,5 cm² vs. GC14 1,0 cm² ± 0,3 cm², p = 0,001). Houve fechamento de 90% das feridas no GC14. No GR14, 60% das feridas foram reepitelizadas enquanto 40% permaneceram ulceradas. No GC7, 70% das feridas de permaneceram ulceradas e 30% foram reepitelizadas. Já no GR7, 8%, foram reepitelizadas e 92% permaneceram ulceradas. Conclusão: A radiofrequência tem influência negativa no processo cicatricial, mostrando que, nos ratos que receberam a radiofrequência, o quadrado permaneceu ulcerado.

Morphological analysis of second-intention wound healing in rats submitted to 16 J/cm 2 λ 660-nm laser irradiation.

Background and Objectives : Low-level laser therapy (LLLT) has been extensively applied to improve wound healing due to some biostimulatory properties presented by laser arrays apparently able to accelerate the cicatricial repair of soft tissue injuries. However, many controversial results have been reported in the literature, probably as a result of the wide sort of different protocols of photobiomodulation employed in those experiments. The goal of this study was to investigate the effect of a low-dose protocol of LLT on the intensity of the inflammatory response and the pattern of collagen fibers' deposition during second-intention wound healing in rodents. Materials and Methods : Standard-sized wounds were carried out in the back of 24 male rats. Half of them underwent LLLT treatment (16 J/cm 2 ) at 660 nm delivered for 7 days. Eight and 14 days after the wounds were performed, the repairing area was removed and stained in HE and Masson's trichrome, and the inflammatory response, epithelization, and collagen fiber depositions were evaluated. Results : We found that LLLT was able to slightly reduce the intensity of the inflammatory reaction as well as to enhance substantially the epithelization process at both 8 th and 14 th days. In addition, it also appeared to stimulate the deposition of collagen fibers at the final stages of wound healing. Conclusions : The LLLT protocol tested in this study resulted in some improvements in second-intention wound healing in rodents.

Facial resurfacing of atrophic acne scars using high-energy pulsed carbon dioxide laser

Background and treatment of atrophic facial acne scars has been limited to the use of traditional methods such as dermabrasion and chemical peels for many years. Recently, high-energy pulsed carbon dioxide [CO 2] laser has been introduced for cutaneous resurfacing. This study was designed to determine the effectiveness and safety of high energy pulsed CO 2 laser in the treatment of facial atrophic acne scars and the occurrence of side effects. Patients and in this study, twenty-two patients with skin phototypes I. II, and III and moderate to severe atrophic facial acne scars were included. Each patient received one high-energy pulsed CO 2 laser treatment session using identical laser parameters by the same laser surgeon. Base line and postoperative clinical assessments and photographs were obtained in all patients. there was 90.5% average clinical improvement observed in acne scars following laser treatment. Side effects were limited to transient hyperpigmentation [4.5% of patients] lasting an average of 3 months. Prolonged erythema [2 months average] was usual and was considered a normal healing response. There was no hypoigmentation, hypertrophic scarring or skin infection following laser treatment. high-energy pulsed CO 2 laser proved to be a safe and effective method in the treatment of atrophic facial acne scars