Evaluation of low-level laser therapy of osteoblastic cells.
OBJECTIVE
The purpose of the present study was to evaluate the effect of biomodulation on osteoblastic cells using a gallium-aluminium-arsenide diode laser.


BACKGROUND
Low-level laser therapy (LLLT) is a non-pharmacological therapeutic resource to which biological tissues respond well, producing such effects as the acceleration of bone formation and bone repair.


METHODS
Osteoblastic cell cultures (OFCOL II) were irradiated with a gallium-aluminium-arsenide diode laser (GaAlAs lambda = 830 nm; 50 mW; 3 J/cm(2); 600-microm-diameter optical fiber) and divided into two groups: group 1--irradiated cells, and group 2--non-irradiated cells. Irradiation occurred at 24-h intervals for a total of 3 d. After each interval, the cells were marked with Mito Tracker Orange dye to assess the biostimulatory effect on mitochondrial activity and cell proliferation using an MTT assay.


RESULTS
Intense grouping of mitochondria in the perinuclear region was observed at 24 h and 48 h following irradiation. Changes from a filamentous to a granular appearance in mitochondrial morphology and mitochondria distributed throughout the cytoplasm were observed 72 h following proliferation. Such changes led to an in vitro proliferation process, as confirmed by the MTT assay.


CONCLUSIONS
LLLT has shown itself capable of altering mitochondrial activity and the population of OFCOL II cells.
Pires Oliveira
Deise A A
DA
Laboratório de Dinâmica de Compartimentos Celulares, Instituto de Pesquisa e Desenvolvimento, UNIVAP, São José dos Campos, São Paulo, Brazil.
de Oliveira
Rodrigo Franco
RF
Zangaro
Renato Amaro
RA
Soares
Cristina Pacheco
CP