Avaliação histológica, tomográfica e física do efeito da LLLT na distração osteogênica em mandíbulas de coelhos

• Autor(a) principal: Kreisner, Paulo Eduardo
• Data de Publicação: 2009
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional PUCRS
• Texto Completo: http://hdl.handle.net/10923/374
• topic: ODONTOLOGIA; TRAUMATOLOGIA BUCOMAXILOFACIAL; CIRURGIA BUCOMAXILOFACIAL; LASER - ODONTOLOGIA; OSTEOGÊNESE POR DISTRAÇÃO; REGENERAÇÃO ÓSSEA; MATERIAIS - TESTES; TOMOGRAFIA; MICROSCOPIA

The purpose of this research was to evaluate bone repair in defects created by fracture with or without distraction osteogenesis in rabbit lower jaws stimulated with low level laser therapy (LLLT – 830nm) by histology, computerized tomography and mechanical properties. 10 rabbits underwent surgery in order to have histologic analysis (four control and six experimental) and five rabbits to tomographic and mechanical analysis (one not broken, not distracted and not irradiated; one broken, not distracted and not irradiated; one broken, not distracted and nor irradiated; one broken, distracted and not irradiated; one broken, distracted and irradiated). In order to achieve the distracted bone, the following protocol was used latency period – three days, activation period-seven days 0.7mm/d, consolidation period- 10 days. The animals were irradiated with infrared laser (GaAl) As (λ=830nm, 40mW) with 10J/cm2 dose per spot applied directly to the distraction osteogenesis site during the consolidation stage at 48hy intervals. Histologically, the area of the new bone was higher on irradiated group (57.89%) than the control (46.75%), p=0.006. The tomographic analysis shows higher bone density, measured by Hounsfield Units (HU) on the broken bone irradiated with laser and better uniform repair. The mechanical properties were the same in the broken bone. On the distracted bone, the hardness was similar in broken groups, but the laser modified the elastic modulus in the these rabbits.