Anti-inflammatory effects of low-level laser therapy (LLLT) with two different red wavelengths (660 nm and 684 nm) in carrageenan-induced rat paw edema.

It has been suggested that low-level laser therapy (LLLT) can modulate inflammatory processes. The aim of this experiment was to investigate what effects red laser irradiation with two different wavelengths (660 nm and 684 nm) on carrageenan-induced rat paw edema and histology. Thirty two male Wistar rats were randomly divided into four groups. One group received a sterile saline injection, while inflammation was induced by a sub-plantar injection of carrageenan (1 mg/paw) in the three other groups. After 1 h, LLLT was administered to the paw in two of the carrageenan-injected groups. Continuous wave 660 nm and 684 nm red lasers respectively with mean optical outputs of 30 mW and doses of 7.5 J/cm(2) were used. The 660 nm and 684 nm laser groups developed significantly (p<0.01) less edema (0.58 ml [SE+/-0.17] ml and 0.76 ml [SE+/-0.10] respectively) than the control group (1.67 ml [SE+/-0.19]) at 4h after injections. Similarly, both laser groups showed a significantly lower number of inflammatory cells in the muscular and conjunctive sub-plantar tissues than the control group. We conclude that both 660 nm and 684 nm red wavelengths of LLLT are effective in reducing edema formation and inflammatory cell migration when a dose of 7.5 J/cm(2) is used.

Homogenous demineralized dentin matrix and platelet-rich plasma for bone tissue engineering in cranioplasty of diabetic rabbits: biochemical, radiographic, and histological analysis.

This study evaluated the effects of homogenous demineralized dentin matrix (HDDM) slices and platelet-rich plasma (PRP) in surgical defects created in the parietal bones of alloxan-induced diabetic rabbits, treated with a guided bone regeneration technique. Biochemical, radiographic, and histological analyses were performed. Sixty adult New Zealand rabbits were divided into five groups of 12: normoglycaemic (control, C), diabetic (D), diabetic with a PTFE membrane (DM), diabetic with a PTFE membrane and HDDM slices (DM-HDDM), and diabetic with PTFE membrane and PRP (DM-PRP). The quantity and quality of bone mass was greatest in the DM-HDDM group (respective radiographic and histological analyses: at 15 days, 71.70 ± 16.50 and 50.80 ± 1.52; 30 days, 62.73 ± 16.51 and 54.20 ± 1.23; 60 days, 63.03 ± 11.04 and 59.91 ± 3.32; 90 days, 103.60 ± 24.86 and 78.99 ± 1.34), followed by the DM-PRP group (respective radiographic and histological analyses: at 15 days 23.00 ± 2.74 and 20.66 ± 7.45; 30 days 31.92 ± 6.06 and 25.31 ± 5.59; 60 days 25.29 ± 16.30 and 46.73 ± 2.07; 90 days 38.10 ± 14.04 and 53.38 ± 9.20). PRP greatly enhanced vascularization during the bone repair process. Abnormal calcium metabolism was statistically significant in the DM-PRP group (P<0.001) for all four time intervals studied, especially when compared to the DM-HDDM group. Alkaline phosphatase activity was significantly higher in the DM-HDDM group (P<0.001) in comparison to the C, D, and DM-PRP groups, confirming the findings of intense osteoblastic activity and increased bone mineralization. Thus, HDDM promoted superior bone architectural microstructure in bone defects in diabetic rabbits due to its effective osteoinductive and osteoconductive activity, whereas PRP stimulated angiogenesis and red bone marrow formation.

Amniotic membrane as a biological dressing for 5-fluoruracil-induced oral mucositis in rats.

Oral mucositis is a reaction to chemoradiation therapy during cancer treatment. The aim of this study was to investigate the use of amniotic membrane as a biological dressing for oral mucositis lesions in rats. Sixty Wistar rats were divided into three groups (n = 20): control, 5-fluoruracil (5-FU), 5-fluoruracil + amniotic membrane (5-FU+AM). Each group was subdivided (n = 5) according to the time interval to sacrifice (3, 7, 14, and 21 days). Histology (haematoxylin-eosin staining) and immunocytochemistry (anti-rat antibodies CD4, CD8, VEGF, and PCNA) were evaluated. Immunocytochemistry results were analyzed using one-way ANOVA and Tukey tests. The amniotic membrane (5FU+AM) played an important role in cell proliferation (PCNA 3 days 27.08 ± 4.65, 7 days 27.90 ± 3.34) and especially in neovascularization (VEGF 3 days 23.00 ± 1.40, 7 days 26.00 ± 0.95) for all time intervals, when compared to 5-FU (PCNA 3 days 23.12 ± 1.61, 7 days 37.21 ± 1.20; VEGF 3 days 17.05 ± 1.51, 7 days 8.45 ± 1.35) and control (PCNA 3 days 29.99 ± 0.92, 7 days 16.33 ± 2.88; VEGF 3 days 13.65 ± 0.55, 7 days 15.70 ± 1.39). It was biocompatible, showing significant differences compared to the other groups in CD4 (F = 40.72; P = 0.001) and CD8 (F = 69.99, P = 0.001) staining together, only during the inflammation phase (7 days). Amniotic membrane presented biocompatibility and stimulated cell proliferation and neovascularization, functioning as a promising biological dressing.

Aspecto histológico da reparação óssea maxilar após enxerto autógeno influenciado pelo uso de laser ASGALL e de BMP / Histologic aspect of maxillary bone repairing after autogenous graft influenced by the use of ASGAAL Laser and BMP

Com a finalidade de obter uma reparação óssea capaz de suportar cargas para implantes, são utilizados enxertos de osso autógeno que apresentam superioridade sobre outros. O uso de laser e BMP como bioestimuladores da reparação óssea são freqüentemente utilizados. Foram selecionados oito pacientes com necessidades de enxerto ósseo para instalação de implantes na região da maxila anterior. A àrea doadora autógena foi a sínfise mentoniana. Após 150 dias, por ocasião da cirurgia óssea de colocação do implante, foi removida a região da interface enxerto-leito com auxílio de uma broca trefina de 3mm de diâmetro. Os resultados mostraram a formação de um tecido ósseo do tipo compacto com grandes cavidades medulares. Observou-se maior número de osteócitos nos grupos tratados. O tecido medular apresentou-se com aspecto fibroso nos grupos G2 e G4. Concluímos, assim, que o uso isolado de BMP e isolado de laser estimulam a proliferação celular e o uso conjugado de ambos potencializam seus efeitos.