BACKGROUND AND OBJECTIVE: The authors investigated the effects of low level laser irradiation on the proliferation rate of human gingival fibroblasts (HGF) in vitro. STUDY DESIGN/ MATERIALS AND METHODS: HGF were obtained from gingival connective tissue explants and cultured under standard conditions. 110 cell cultures in their logarithmic growth phase were spread on 96-well tissue culture plates and were irradiated at energy fluences of 1.96-7.84 J/cm(2). Another 110 cultures served as control. An 809-nm semiconductor laser operated at a power output of 10 mW in the cw-mode was used. The time of exposure varied between 75 and 300 seconds. Laser treatment was performed alternatively once, twice, and three times at a 24-hour interval. After lasing, incubation was continued for 24 hours. The proliferation rate was determined by means of fluorescence activity of a redox indicator added to the cell culture. Proliferation was determined 24, 48, and 72 hours after irradiation and expressed in relative fluorescence units (RFU). RESULTS: The irradiated cells revealed a considerably higher proliferation activity. The differences were highly significant 24 hour after irradiation (Mann-Whitney U-test, P < 0.05) but decreased in an energy-dependent manner after 48 and 72 hour after irradiation. CONCLUSIONS: A cellular effect of the soft laser irradiation on HGF is evident. Its duration, however, seems to be limited. These findings might be clinically relevant, indicating that repeated treatments are necessary to achieve a positive laser effect in clinical applications. Copyright 2002 Wiley-Liss, Inc.
BACKGROUND AND OBJECTIVE: The authors investigated the effects of low level laser irradiation on the proliferation rate of human gingival fibroblasts (HGF) in vitro. STUDY DESIGN/ MATERIALS AND METHODS:HGF were obtained from gingival connective tissue explants and cultured under standard conditions. 110 cell cultures in their logarithmic growth phase were spread on 96-well tissue culture plates and were irradiated at energy fluences of 1.96-7.84 J/cm(2). Another 110 cultures served as control. An 809-nm semiconductor laser operated at a power output of 10 mW in the cw-mode was used. The time of exposure varied between 75 and 300 seconds. Laser treatment was performed alternatively once, twice, and three times at a 24-hour interval. After lasing, incubation was continued for 24 hours. The proliferation rate was determined by means of fluorescence activity of a redox indicator added to the cell culture. Proliferation was determined 24, 48, and 72 hours after irradiation and expressed in relative fluorescence units (RFU). RESULTS: The irradiated cells revealed a considerably higher proliferation activity. The differences were highly significant 24 hour after irradiation (Mann-Whitney U-test, P < 0.05) but decreased in an energy-dependent manner after 48 and 72 hour after irradiation. CONCLUSIONS: A cellular effect of the soft laser irradiation on HGF is evident. Its duration, however, seems to be limited. These findings might be clinically relevant, indicating that repeated treatments are necessary to achieve a positive laser effect in clinical applications. Copyright 2002 Wiley-Liss, Inc.
Authors: Carlos de Paula Eduardo; Patricia Moreira de Freitas; Marcella Esteves-Oliveira; Ana Cecília Corrêa Aranha; Karen Müller Ramalho; Alyne Simões; Marina Stella Bello-Silva; Jan Tunér Journal: Lasers Med Sci Date: 2010-07-17 Impact factor: 3.161
Authors: Luciane Hiramatsu Azevedo; Fernanda de Paula Eduardo; Maria Stella Moreira; Carlos de Paula Eduardo; Márcia Martins Marques Journal: Lasers Med Sci Date: 2006-05-13 Impact factor: 3.161
Authors: Fernanda G Basso; Camila F Oliveira; Cristina Kurachi; Josimeri Hebling; Carlos A de Souza Costa Journal: Lasers Med Sci Date: 2013-02 Impact factor: 3.161