title: Influence of different power densities of LILT on cultured human fibroblast growth : a pilot study.
abstract: The aim of this in vitro study was to analyze the influence of different power densities of low-intensity laser therapy (LILT) on the biomodulation of human gingival fibroblasts. The cells were cultured in nutritional deficit. Laser irradiation was carried out with a GaAlAs diode laser (lambda-660 nm, 2 J/cm2). The irradiation was done twice with 12-h interval using the punctual technique, at continuous mode and in contact. The experimental groups were: I, control, nonirradiated; II, power of 10 mW and intensity approximately or equal to 142.85 mW/cm2; III, 29 mW and 428.57 mW/cm2. Growth curves were obtained by using the trypan blue dye exclusion assay. The cell growth of the irradiated groups was significantly higher than control group (P<or=0.05). The cultures of Group II presented cell growth superior to that of Group III. Based on the conditions of this study, we concluded that the power density influences cell growth in an inversely proportional manner.
authors.affiliation: Department of Stomatology, School of Dentistry, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Luciane Hiramatsu
authors.initials: LH
authors.lastname: Azevedo
authors.forename: Fernanda
authors.initials: F
authors.lastname: de Paula Eduardo
authors.forename: Maria Stella
authors.initials: MS
authors.lastname: Moreira
authors.forename: Carlos
authors.initials: C
authors.lastname: de Paula Eduardo
authors.forename: Márcia Martins
authors.initials: MM
authors.lastname: Marques
mesh_terms: D002452:Cell Count; D018929:Cell Culture Techniques; D049109:Cell Proliferation / Q000528:radiation effects*; D005347:Fibroblasts / Q000502:physiology* / Q000528:radiation effects*; D005881:Gingiva / Q000166:cytology / Q000528:radiation effects; D006801:Humans; D028022:Low-Level Light Therapy / Q000379:methods*; D010865:Pilot Projects; D013997:Time Factors