Dose-responses of Stem Cells from Human Exfoliated Teeth to Infrared LED Irradiation

Abstract

Despite several reports regarding tissue regeneration, including pulp repair induced by different light sources, only limited data have been reported concerning the effects of light-emitting diodes (LED) on stem cells from human exfoliated deciduous teeth (SHEDs). The aim of this study was to evaluate the effects of different energy densities of infrared LED on the cell viability, number of cells and mineralized tissue production by SHEDs. SHEDs were obtained from near-exfoliation primary teeth (n=3), seeded in plain DMEM (10 4 cells/cm 2 ), and irradiated by a LED prototype (LEDTable 850 nm, 40 mW/cm 2 ) delivering 0 (control), 2, 4, 8, 15 or 30 J/cm 2 (n=9). Cell viability (MTT assay), cell proliferation (trypan blue assay), and mineralized nodule (MN) formation (alizarin red stain) were assessed 12 and 72 h post-irradiation. Data were subjected to Kruskal-Wallis and Mann-Whitney tests (α=0.05). Cells irradiated with 2 or 4 J/cm 2 exhibited higher metabolism at 72 h, and all energy densities provided increase in cell proliferation after 12 h. Regarding MN formation, the best results were observed at 72 h after SHED irradiation with 8 and 15 J/cm 2 . It was concluded that the cell viability, cell number and MN formation by pulp cells are enhanced after exposure to infrared LED irradiation. Overall, the greatest SHED biostimulation was obtained with 4 and 8 J/cm 2 . D o s e -r e s p o n s e s o f S t e m C e l l s f r o m H u m a n E x f o l i a t e d Te e t h t o I n f r a r e d L E D I r r a d i a t i o n

Photobiomodulation effect of red LED (630 nm) on the free radical levels produced by pulp cells under stress conditions

“…The irradiation of cultured pulp cells was performed using a LED table; this device is widely employed in laboratorial studies in this research field (Fig. 1) [2,22,23,[39][40][41]. The LED table was developed by the Optical Group (OG) of the Optics and Photonics Research Center (Centro de Pesquisa em Óptica e Fotônica -CePOF) of the São Carlos Institute of Physics (IFSC) at the University of São Paulo (USP).…”

“…Clinical and laboratory studi es have evaluat ed the eff ect of photobiomodulation on the healing of different tissues, such as the muscle and cartilage [11,12], neuronal cells [13,14], bone [15,16], and the dentin-pulp complex [2,17,18]. Photobiomodulation using light emitting diodes (LED) has been widely assessed in dentistry and is considered a potential adjuvant treatment for stimulating pulpal healing [2,[18][19][20][21][22][23]. LED irradiation with either infrared or red light enhances the proliferation of human and rodent pulp cells [21][22][23] as well as cultured odontoblast-like cells [2].…”

“…Photobiomodulation using light emitting diodes (LED) has been widely assessed in dentistry and is considered a potential adjuvant treatment for stimulating pulpal healing [2,[18][19][20][21][22][23]. LED irradiation with either infrared or red light enhances the proliferation of human and rodent pulp cells [21][22][23] as well as cultured odontoblast-like cells [2]. Moreover, dentin protein expression and production have increased because of the use of these wavelengths [20,23].…”

“…LED irradiation with either infrared or red light enhances the proliferation of human and rodent pulp cells [21][22][23] as well as cultured odontoblast-like cells [2]. Moreover, dentin protein expression and production have increased because of the use of these wavelengths [20,23]. Photobiomodulation induces in vivo mineralized tissue formation, decreased inflammatory cell infiltration, and stimulated tissue vascularization after pulpal exposure in rat molars [19].…”

Influência de diferentes densidades de energia do laser de baixa intensidade em fibroblastos derivados da polpa de dentes decíduos

“…Visto que linhagens celulares variadas podem apresentar resultados divergentes após a irradiação com LBI devido às diferenças fenotípicas e genotípicas , a investigação da correta combinação dos parâmetros de irradiação com os diferentes tipos celulares é fundamental para se alcançar os efeitos clínicos desejados BAXTER, 2010;HADIS et al, 2016). A maioria dos estudos avaliam os efeitos da fototerapia para aplicação odontológica sobre cultura primária de fibroblastos gengivais (ALMEIDA-LOPES et al, 2001;KREISLER et al, 2002;POURZARANDIAN et al, 2005;DAMANTE et al, 2009), linhagens celulares imortalizadas ou contínuas (PEREIRA et al, 2002;AZEVEDO et al, 2006;FERREIRA et al, 2009), células-tronco derivadas da polpa dentária de dentes decíduos (EDUARDO et al, 2008;TURRIONI et al, 2015;FERNANDES et al, 2016) e permanentes (ZACCARA et al, 2015. Miyata et al (2006), avaliaram os mecanismos envolvidos na proliferação celular de fibroblastos derivados de cultura primária de tecido pulpar de dentes terceiros molares.…”