Fotoengenharia do processo de reparo ósseo induzido pela laserterapia de baixa potência (GaAlAs): estudo em fêmures de ratos

• Autor(a) principal: Guimarães, Karis Barbosa
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional PUCRS
• Texto Completo: http://hdl.handle.net/10923/367
• topic: ODONTOLOGIA; LASER DE BAIXA INTENSIDADE; RATOS - EXPERIÊNCIAS; OSSOS - DESENVOLVIMENTO; LASER - TERAPIA; TRAUMATOLOGIA BUCOMAXILOFACIAL

The main objective of the present study was to evaluate, through histological and morphometric analysis, the biomodulation process of bone repair on the periosteum, endosteum and medullary regions in femorals cavities of mice, which were submitted to diode infrared laser radiation (GaAlAs). 30 male mice Wistar were used, weighing between 350 and 550 grams, distributed randomly in two groups, the control (GI) and the experimental one (GII) and six subgroups in accordance with the period of observation of the animals. For the groups, control and experimental, there has been designated each 13 and 14 animals, respectively. The experimental groups received low power Laser therapy (LLLT), in the experimental bone cavity, identified through a Titanium screw, which was previously fixed, 8mm from the cavity. In group GI, a surgical protocol was carried out, without laser application. In groups GII, infrared laser was used (λ= 830 nm, 6 J/cm2, 50mW, 120s) of punctual and continuous potency was used. The radiation period was every 48 hours, initiated immediately after the injury production, in the medullar cavity. The death of the animals occurred on the 07th, 15th, 21st days. For the histological analysis, the routine processing was carried out, with the HE and picrosirius technique. The laminas were studied through descriptive and morphometric analysis. The evaluated tissue phenomenons were the inflammatory answer and bone neoformation. For the morphometric analysis the averages of mineralized new bone had been determined and the anatomical localizations of these had been made. The results achieved by this study demonstrated that in the groups where laser was used in the experimental bone cavity (GII) the bone healing was quantitatively better if compared to the results achieved by GI, with evidences of bigger maturation of organic bone matrix and standards of osteogenesis in more advanced periods of training in the initial periods of the experiment. However, according to morphometric analysis, the positive biomodulation was presented bigger when comparative to the groups not submitted to the LLLT. The histomorphometric mapping evidenced the production of stimulations positive biomodulation only in the localization of periosteum, thus denoting, greater potential of penetration, stimulation and acceleration of the bone consolidation in the cortical region of the bone defect. The results led to the conclusion that the use of low power laser therapy with this protocol causes positive biomodulation effects on the healing process on periosteum and can be used as coadjuvant in the bone repair process.