Low-Level Laser Therapy on Bone Repair of Rat Tibiae Exposed to Ionizing Radiation

Autor(es)

Fracher Abramoff, Meire Maman ^[1] ; Pereira, Max Domingues ^[1] ; de Seixas Alves, Maria Teresa ^[2] ; Segreto, Roberto Araujo ^[3] ; Guilherme, Arnaldo ^[4] ; Ferreira, Lydia Masako ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Dept Surg, Div Plast Surg, Sao Paulo - Brazil

^[2] Univ Fed Sao Paulo, Dept Pathol, Sao Paulo - Brazil

^[3] Univ Fed Sao Paulo, Div Radiotherapy, Dept Expt Clin Oncol, Sao Paulo - Brazil

^[4] Univ Fed Sao Paulo, Dept Otolaryngol Head & Neck Surg, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Photomedicine and Laser Surgery; v. 32, n. 11, p. 618-626, NOV 1 2014.
• Citações Web of Science: 3

Resumo

Objective: The purpose of this study was to evaluate the effects of low-level laser therapy (LLLT) on the repair of rat tibiae exposed to ionizing radiation (IR). Background data: IR causes structural changes that delay bone tissue repair. Properly dosed, LLLT improves the bone repair process. Methods: Seventy-two healthy Wistar rats were distributed into the following groups: Group I, sham control; Group II, LLLT; Group III, IR; and Group IV, IR and LLLT. Groups III and IV received a single dose (30 Gy) of gamma radiation and underwent surgery 28 days later. A noncritical sized bone defect (diameter 2.5 mm) was surgically created in all groups. Groups II and IV received three applications of postsurgical LLLT (GaAlAs, 808 nm, 100 mW, 0.028 cm(2), 3.57 W/cm(2), 20 sec, 2 J, approximately equal to 71.4 J/cm(2)) on alternate days. Histomorphometry was assessed following digital image analysis. Results: The samples were evaluated on days 7, 14, and 21 after surgery; the IR protocol resulted in a significant reduction (p<0.018) in bone formation in Group III compared with Group I. Significant increases (p<0.006) in newly formed bone were noted in Group IV compared with Group III. No significant differences were observed between Group I and Group IV. Conclusions: LLLT increased the newly formed bone area during the initial phase of the tibiae repair process in rats exposed to IR. (AU)

• Processo FAPESP: 10/51626-9 - Laser de baixa intensidade na reparação de tíbia de ratos submetidas a radiação ionizante
• Beneficiário: Max Domingues Pereira
• Modalidade de apoio: Auxílio à Pesquisa - Regular