Effects of photobiomodulation with blue Light Emitting Diode (LED) on the healing of skin burns.

The management of skin burns is still challenging. Among the therapeutic methods used, there are topical treatments with pharmacological and herbal agents, low-intensity therapeutic ultrasound, use of biomaterials, reconstructive techniques and photobiomodulation therapy. The aim of this study was to evaluate the effects of photobiomodulation with blue Light Emitting Diode (LED) on burn healing. Fifty Wistar rats were divided into control (CTRL) (n = 25) and blue LED (LED) (n = 25), with subgroups (n = 5) for each time of euthanasia (7, 14, 21, 28 and 32 days). Treated animals were daily irradiated (470 nm, 1W, 0.44 W/cm2, 50 J/cm2). Clinical evaluations were performed and the Wound Retraction Index (WRI) was determined. Histological sections were submitted to hematoxylin-eosin, toluidine blue and the immunohistochemical technique, with anti-α-SMA and anti-TGF-ß1 antibodies. All data were directly collected by previously calibrated evaluators in a blind manner. The values were included in a statistical program. For all statistical tests used, 5% significance level (p < 0.05) was considered. No statistically significant differences in WRI between groups were observed (p > 0.05). Re-epithelialization was higher using LED at 7 and 14 days (p < 0.05) and greater amount of inflammatory cells was observed at 7 days (p = 0.01). With LED at 21 and 32 days, greater number of mast cells were observed (p < 0.05), as well as smaller number of myofibroblasts at 14, 21, 28 and 32 days (p < 0.05) and lower percentage of TGF-ß1 positive cells in the conjunctiva at 7, 14 and 21 days (p < 0.05). Negative correlations were observed in LED between the percentage of TGF-ß1 in the epithelium and the mean number of inflammatory cells and number of myofibroblasts (p < 0.05). The results suggest that, depending on the period, blue LED can modulate the healing processes of third-degree skin burns, such as re-epithelialization, inflammatory response, mast cell concentration, myofibroblast differentiation and TGF-ß1 immunoexpression. Despite these effects, this therapy does not seem to have significant influence on the retraction of these wounds. Future studies, using different protocols, should be carried out to expand the knowledge about the photobiomodulatory mechanisms of this type of light in the healing process.

Effects of photobiomodulation therapy with red LED on inflammatory cells during the healing of skin burns.

The aim of this study was to evaluate the effects of red light emitting diode (LED) photobiomodulation therapy protocol on inflammatory cells during the healing of third-degree skin burns. Fifty Wistar rats were randomly divided into control group (CTRL) (n = 25) and red group (RED) (n = 25), with subgroups (n = 5) for each time of euthanasia (7, 14, 21, 28, and 32 days). Treatment animals were daily irradiated (630 nm ± 10 nm, 300 mW, 9 J/cm2 per point, 30 s, continuous emission mode) at the 4 angles of the wound (total: 36 J/cm2). After specimen removal, histological sections were stained with hematoxylin and eosin for quantitative analysis of the inflammatory infiltrate (neutrophils and lymphocytes) under light microscopy. Greater number of inflammatory cells was observed in irradiated groups when compared to CTRL at 7, 14, 21, and 28 days, but with statistically significant difference only at 14 days (p = 0.02). At 32 days, higher inflammatory cell value was observed in CTRL when compared to RED, but with no statistically significant difference (p = 0.91). The results suggest that red LED, according to the protocol used, modulates the number of inflammatory cells in the early stages of the healing of third-degree skin burns. Nevertheless, this low-intensity light therapy may not, be efficient in reducing the number of neutrophils and lymphocytes in advanced stages of the repair process of skin burns. Further studies with other therapy protocols are needed to assess the effects of this type of light on the inflammatory response of skin burns.

Low-level laser therapy is effective in controlling postoperative pain in lower third molar extractions: a systematic review and meta-analysis.

This systematic review aimed to evaluate the effectiveness of low-level laser therapy in controlling postoperative pain in lower third molar extractions. A search was carried out in MEDLINE/PubMed, Web of Science and Cochrane Library (CENTRAL) databases, using the "low-level laser therapy", "photobiomodulation therapy", "impacted mandibular third molar", "mandibular third molar", "third molar extraction" descriptors and 2625 studies were found, including only randomized clinical trials published until July 2020, with no restrictions on language and country of study. Selected studies were submitted to initial screening based on the reading of titles, abstracts and full article, and duplicate studies were excluded. Overall, 2562 articles were found, of which only 15 randomized clinical trials were included in this review. A total of 648 patients (16-44 years) who received low-level laser therapy as an intervention and placebo in their control group were evaluated. The pain evaluation criterion was the Visual Analog Scale (VAS) on the second and seventh days after surgery. Photobiomodulation with low-level laser showed statistically significant reduction in postoperative pain in lower third molar extractions, both on the second (MD: - 0.59; CI: - 0.92, - 0.27) and seventh day after surgery (MD: - 0.76; CI: - 1.21, - 0.32).

Photobiomodulation of red and green lights in the repair process of third-degree skin burns.

The aim of this study was to evaluate the photobiomodulation of red and green lights in the repair process of third-degree skin burns in rats through clinicopathological and immunohistochemical parameters. Sixty male Wistar rats were divided into three groups: control (CTRL) (n = 20), red LED (RED) (n = 20), and green LED (GREEN) (n = 20), with subgroups (n = 5) for each time of euthanasia (7, 14, 21, and 28 days). Daily applications in RED (λ630 ± 10 nm, 300 mW) and GREEN groups (λ520 ± 30 nm, 180 mW) were performed at four points of the wound (total 36 J/cm2 in RED and 240 J/cm2 in GREEN). After euthanasia, the wound retraction index (WRI) was evaluated. In histological sections, the re-epithelialization degree, the angiogenic index (AI), and the amount of myofibroblasts in wounds were analyzed. At 14 and 21 days, the RED group induced higher re-epithelialization and WRI compared to CTRL (p > 0.05) and GREEN groups (p < 0.05). At 7 and 14 days, greater AI were observed in the GREEN group, with significant difference in relation to CTRL group at 7 days (p < 0.05). At 21 and 28 days, a trend was observed for greater amount of myofibroblasts in the GREEN group, with significant difference in relation to CTRL group at 21 days (p < 0.05). The results suggest greater potential of the green light to stimulate angiogenesis in the initial periods and myofibroblastic differentiation in the final periods of the repair of third-degree skin burns. Red light may stimulate further re-epithelialization and wound retraction, especially in advanced repair phases.

Brazilian Scientific Research about Acupuncture in Dentistry: Bibliometric Analysis of the Papers Presented at SBPqO Meetings / A Pesquisa Científica Brasileira Sobre Acupuntura na Odontologia: Análise Bibliométrica dos Trabalhos Apresentados nas Reuniões da SBPqO

The aim of this study was to investigate the Brazilian scientific production about acupuncture in dentistry, outlining the profile of the works about the subject presented at the Meetings of the Brazilian Society of Dental Research (SBPqO). It was a cross-sectional study, with a quantitative approach, based on secondary data. An analysis of all abstracts presented in the last ten SBPqO Meetings (2009-2018) published in the annals of the event was carried out. For the research the location of the term "acupuntura" or "acupuncture" among the abstracts was realized and the following information was collected: type of institution that carried out the research (public or private), Brazilian region where it was realized, area or specialty of dentistry and whether it involved humans or animals. Of the 26,514 dental research abstracts published in the annals, only 27 papers were experimental studies or systematic reviews about the subject. Of the total, 23 (85.2%) were developed in public institutions, 15 (55.6%) did not receive financial support 20 (74.1%) were carried out in humans and 13 (48.2%) were developed in the Southeast region. Regarding the dental specialty, the majority (70.4%) investigated acupuncture in "Temporomandibular Dysfunction and Orofacial Pain". Therefore, it can be concluded that few acupuncture studies in dentistry have been developed in the last ten years in Brazil, according to the papers presented at the SBPqO Meetings. Thus, it is suggested that research on the subject be carried out and widely disseminated between the academic and professional milieu. (AU)

O objetivo desse estudo foi investigar a produção científica brasileira sobre a acupuntura na odontologia, traçando o perfil dos trabalhos sobre a temática apresentados nas Reuniões da Sociedade Brasileira de Pesquisa Odontológica (SBPqO). Tratou-se de um estudo transversal, com abordagem quantitativa, a partir de dados secundários. Realizou-se uma análise de todos os resumos apresentados nas últimas dez Reuniões da SBPqO (2009-2018) publicados nos anais do evento. Para pesquisa procedeu-se a localização do termo "acupuntura" ou "acupuncture" entre os resumos e foram colhidas as seguintes informações: tipo de instituição que realizou a pesquisa (pública ou privada), região rasileira onde foi realizada, recebimento de auxílio financeiro, área ou especialidade da odontologia e se envolvia humanos ou animais. Dos 26.514 resumos de pesquisa odontológica publicados em anais, apenas 27 trabalhos tratavam de estudos experimentais ou revisões sistemáticas sobre a temática. Do total, 23 (85,2%) foram desenvolvidos em instituições públicas, 15 (55,6%) não receberam auxílio financeiro, 20 (74,1%) foram realizados em humanos e 13 (48,2%) desenvolvidos na região Sudeste do Brasil. Com relação a especialidade odontológica, a maioria (70,4%) pesquisou sobre a acupuntura na "Disfunção Temporomandibular e Dor Orofacial". Os achados do presente estudo indicam que poucas pesquisas abordando a acupuntura na odontologia foram desenvolvidas nos últimos dez anos no Brasil, de acordo com os trabalhos apresentados nas Reuniões da SBPqO. Diante disso, sugere-se que pesquisas sobre o tema sejam realizadas e amplamente divulgadas entre o meio acadêmico e profissionais. (AU)