%0 Journal Article
%T Evaluation of two protocols for low-level laser application in patients submitted to orthodontic treatment
%A Mariana Marquezan
%A Ana Maria Bolognese
%A M£¿nica Tirre de Souza Ara¨²jo
%J Dental Press Journal of Orthodontics
%D 2013
%I Dental Press Editora
%X INTRODUCTION: Different low-level laser (LLL) irradiation protocols have been tested to accelerate orthodontic tooth movement (OTM). Nevertheless, divergent results have been obtained. It was suggested that the stimulatory action of low level laser irradiation occurs during the proliferation and differentiation stages of bone cellular precursors, but not during later stages. OBJECTIVE: The purpose of this study was to determine the effect of two protocols of LLL irradiation on experimental tooth movement: One with daily irradiations and another with irradiations during the early stages. METHODS: Thirty-six rats were divided into control groups (CG1, CG2, CG3) and irradiated groups (IrG1, IrG2, IrG3) according to the presence of: experimental tooth movement, laser irradiation, type of laser irradiation protocol and date of euthanasia (3th or 8th day of experiment). At the end of experimental periods, a quantitative evaluation of the amount of OTM was made and the reactions of the periodontium were analyzed by describing cellular and tissue reactions and by counting blood vessels. RESULTS: The amount of OTM revealed no significant differences between groups in the same experimental period (p < 0.05). Qualitative analysis revealed the strongest resorption activity in irradiated groups after seven days, especially when using the daily irradiation protocol. There was a higher number of blood vessels in irradiated animals than in animals without orthodontic devices and without laser irradiation (p < 0.05). CONCLUSION: Moreover, angiogenesis was verified in some of the irradiated groups. The irradiation protocols tested were not able to accelerate OTM and root resorption was observed while they were applied. INTRODU  O: diferentes protocolos de irradia  o por laser de baixa pot¨ºncia (LBP) t¨ºm sido testados para potencializar o movimento ortod ntico; entretanto, h¨¢ resultados divergentes. Foi sugerido que seu efeito bioestimulador ocorre nas fases de prolifera  o e diferencia  o celular, n o agindo em est¨¢gios tardios. OBJETIVO: avaliar o efeito de dois protocolos de irradia  o do LBP na movimenta  o ortod ntica: um com irradia  es di¨¢rias e outro em que irradia  es foram realizadas apenas nos per¨ªodos iniciais. M¨¦TODOS: trinta e seis ratos Wistar foram divididos em grupos controles (GC1, GC2 e GC3) e irradiados (GIr1, GIr2 e GIr3), de acordo com a presen a de dispositivo ortod ntico, a presen a de irradia  o, o tipo de protocolo de irradia  o e a data de eutan¨¢sia (3o ou 8o dia de experimento). Ao final dos per¨ªodos experimentais, foram realizadas mensura  es
%K Lasers
%K Terapia a laser de baixa intensidade
%K Movimenta  o dent¨¢ria
%K Agentes indutores da angiog¨ºnese
%K Lasers
%K Low-level laser therapy
%K Tooth movement
%K Angiogenesis inducing agents
%U http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2176-94512013000100009