title: Synthesis of dental matrix proteins and viability of odontoblast-like cells irradiated with blue LED.
abstract: To evaluate the effect of irradiation with light-emitting diode (LED; 455 nm) on the viability and synthesis of dentin matrix proteins by odontoblast-like cells, MDPC-23 cells were cultivated (10(4) cells/cm(2)) in 24-well culture plates. After 12 h incubation in Dulbecco's modified Eagle's medium (DMEM), the cells were submitted to nutritional restriction by means of reducing the concentration of fetal bovine serum (FBS) for an additional 12 h. Cells were irradiated one single time with one of the following energy densities (EDs): 0.5, 2, 4, 10, or 15 J/cm(2) and irradiance fixed at 20 mW/cm(2). Non-irradiated cells served as control. After 72 h, cells were evaluated with regard to viability (methylthiazol tetrazolium technique (MTT)), mineralization nodule (MN) formation, total protein (TP) production, alkaline phosphatase activity (ALP), and collagen synthesis (Sircol), n = 8. The data were submitted to Kruskal-Wallis and Mann-Whitney tests (p > 0.05). There was no statistical difference between the viability of cells irradiated or not (control), for all the EDs. However, an increase in TP was observed for all the EDs when compared with the control group. A reduced ALP activity was seen in all irradiated groups, except for the ED of 0.5 J/cm(2), which did not differ from the control. There was no difference between the irradiated groups and control regarding collagen synthesis, with the exception of the ED of 10 J/cm(2), which inhibited this cell function. Significant reduction in MN occurred only for the EDs of 0.5 and 2 J/cm(2). The single irradiation with blue LED (455 nm), irradiance of 20 mW/cm(2), and energy densities ranging from 0.5 to 15 J/cm(2) exerted no effective biostimulatory capacity on odontoblast-like cells.
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dentistry at Araraquara, Universidade Estadual Paulista-UNESP, Rua Humaitá, 1680, Araraquara, São Paulo, Brazil, 14801-903.
authors.forename: Juliana Rosa Luiz
authors.initials: JR
authors.lastname: Alonso
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dentistry at Araraquara, Universidade Estadual Paulista-UNESP, Rua Humaitá, 1680, Araraquara, São Paulo, Brazil, 14801-903.
authors.forename: Ana Paula Silveira
authors.initials: AP
authors.lastname: Turrioni
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dentistry at Araraquara, Universidade Estadual Paulista-UNESP, Rua Humaitá, 1680, Araraquara, São Paulo, Brazil, 14801-903.
authors.forename: Fernanda Gonçalves
authors.initials: FG
authors.lastname: Basso
authors.affiliation: Department of Physiology and Pathology, School of Dentistry at Araraquara, Universidade Estadual Paulista-UNESP, Rua Humaitá, 1680, Araraquara, São Paulo, Brazil, 14801-903.
authors.forename: Carlos Alberto
authors.initials: CA
authors.lastname: de Souza Costa
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dentistry at Araraquara, Universidade Estadual Paulista-UNESP, Rua Humaitá, 1680, Araraquara, São Paulo, Brazil, 14801-903. jhebling@foar.unesp.br.|Departamento de Clínica Infantil, Faculdade de Odontologia de Araraquara, Rua Humaitá, 1680, Araraquara, Brazil, 14801-903. jhebling@foar.unesp.br.
authors.forename: Josimeri
authors.initials: J
authors.lastname: Hebling
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects; D003094:Collagen / Q000096:biosynthesis; D054023:Lasers, Semiconductor; D009804:Odontoblasts / Q000502:physiology* / Q000528:radiation effects; D051381:Rats; D014074:Tooth Calcification
chemical_list: D003094:Collagen; D000469:Alkaline Phosphatase
keywords: Light; Light-emitting diode; Odontoblasts; Phototherapy