Effect of laser therapy on bone tissue submitted to radiotherapy: experimental study in rats
| Autor: | Darcy de Almeida, Nilza Pereira da Costa, Marleny Elizabeth Márquez de Martínez Gerbi, Elaine Bauer Veeck, André Carlos de Freitas, Viviane Almeida Sarmento, Aparecida Maria Cordeiro Marques, Alessandra Mattos, Luciana Maria Pedreira Ramalho, Samantha Seara Da Cunha |
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| Rok vydání: | 2007 |
| Předmět: |
Male
medicine.medical_specialty medicine.medical_treatment Group ii Biomedical Engineering Bone Marrow Cells Cell Count Bone tissue Osteocytes Bone and Bones Ionizing radiation law.invention Laser therapy law medicine Animals Radiology Nuclear Medicine and imaging Femur Low-Level Light Therapy Rats Wistar business.industry Body Weight Laser Surgery Rats Radiation therapy Haversian System Normal bone medicine.anatomical_structure Nuclear medicine business |
| Zdroj: | Photomedicine and laser surgery. 25(3) |
| ISSN: | 1549-5418 |
| Popis: | The aim of this study was to investigate the effect of laser therapy (lambda = 780 nm) on bone tissue submitted to ionizing radiation.The biostimulation effect of laser in normal bone tissue has already been demonstrated successfully; however its effect on bone tissue submitted to radiotherapy has not yet been studied.Twenty-two Wistar rats were randomly divided into four groups: group I, control (n = 4), submitted only to radiotherapy; group II, laser starting 1 day prior to radiotherapy (n = 6); group III, laser started immediately after radiotherapy (n = 6); group IV, laser 4 weeks after radiotherapy (n = 6). The source of ionizing radiation used was Cobalt 60, which was applied in a single dose of 3000 cGy on the femur. The laser groups received seven applications with a 48-h interval in four points per session of DE = 4 J/cm(2), P = 40 mW, t = 100 sec, and beam diameter of 0.04 cm(2). All animals were killed 6 weeks after radiotherapy.Clinical examination revealed cutaneous erosions on experimental groups (II, III, and IV) starting at the 6th week after radiotherapy. The radiographic findings showed higher bone density in groups II and IV (p0.05) compared to the control group. The results further showed an increase of bone marrow cells, and number of osteocytes and Haversian canals in experimental groups II and IV (p0.05). It was also found an increase of osteoblastic activity, in groups II, III, and IV (p0.05).Laser therapy on bone tissue in rats presented a positive biostimulative effect, especially when applied before or 4 weeks after radiotherapy. However, the use of laser in the parameters above should be used with caution due to epithelial erosions. |
| Databáze: | OpenAIRE |
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