Orientador: Valdir Gouveia Garcia / Reumo: A proposta do presente estudo foi avaliar, histologicamente a influência da terapia do laser em baixa intensidade (LLLT)) sobre o processo de reparo em feridas cutâneas provocadas no dorso de ratos tratados com nicotina. Foram utilizados 115 ratos neste estudo. Cinqüenta e nove ratos receberam injeção subcutânea de solução salina (0,2 ml), enquanto o restante dos animais receberam injeção subcutânea de nicotina (3mg/Kg de peso do animal), duas vezes ao dia durante todo o período experimental. Decorridos 30 dias das aplicações, foi criada uma ferida cirúrgica sobre o dorso de cada animal por meio de um punch ( 8 mm de diâmetro). Os animais que receberam solução salina foram divididos em 2 grupos: Grupo I(Controle)(n=29) - As feridas permaneceram sem nenhum tratamento enquanto as do Grupo II (n=30) foram submetidas a tratamento com LLLT (AlGaAs)660 nm, 40 mW, 3.0 J, 0,56 w/cm2). Os animais que receberam injeção subcutânea de nicotina também foram divididos em 2 grupos. Grupo III (n=29) onde as feridas não receberam nenhum tratamento; e Grupo IV (n=27), no qual os animais receberam tratamento com LLLT (660 nm, 40 mW, 3,0 J, 0,56 W/cm2). Cada...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The purpose of this study was to histologically analyze the influence of low level laser therapy (LLLT) on the healing process of surgically created coetaneous wounds in rats treated with nicotine. One hundred and fifteen rats were used in this study. Fifty nine rats received subcutaneous injection of saline (0,2 ml) while the remaining animals received subcutaneous injection of nicotine (3 mg/kg of body weight) twice a day during all experimental period. After 30 days of either saline or nicotine injection, coetaneous wounds were surgically created on the back of the animals with a punch (8 mm in diameter). The animals that received saline injections were divided into 2 groups: Group I (control) (n= 29) - The wound was left untreated; and Group II (n= 30) - The wound was treated with LLLT (GaAlAs 660 nm, 40 mW, 3.0 J, 0.56 W/cm2). The animals that received nicotine injections were also divided into 2 groups: Group III (n= 29) - The wound was left untreated; and Group IV (n= 27) - The wound was treated with LLLT (GaAlAs 660 nm, 40 mW, 3.0 J, 0.56 W/cm2). Each group was subdivided into sub-groups for euthanasia at either 3, 7 or 14 days post-operative. Block sections were routinely processed for histological analysis using H&E stain. Group III showed delayed epithelial migration and connective tissue organization when compared to Group I. The wounds of Group II presented an...(Complete abstract, click electronic access below) / Mestre