Evaluation of light-emitting diode (LED-660 nm) application over primary osteoblast-like cells on titanium surfaces: an in vitro study.
BACKGROUND
The goal of this study was to evaluate the behavior of neonatal rat calvarial osteoblast-like cells cultured on different implant surfaces and exposed once or three times to a 660-nm light-emitting diode (LED).


METHODS
An LED with a 660-nm wavelength was applied once or three times to cultured cells on standard and modified sandblasted acid-etched surfaces (SLA and SLActive; Straumann, Basel, Switzerland). To analyze the effect of the LED on cell proliferation, numbers, and viability, cells were cultured on titanium discs, and measurements were taken after 72 h. Cell proliferation rates were assessed using a bromodeoxyuridine immunohistochemical technique. Cell morphologies were evaluated by scanning electron microscopy (SEM).


RESULTS
Osteoblast-like cells proliferated on all tested surfaces, with differences among groups in cell counts and DNA synthesis values. The application of one LED treatment caused a significant increase in cell count in the SLActive group in comparison with the SLA group (p = 0.001), whereas the application of three LED treatments caused a significant decrease in cell count in the SLA group compared with the SLActive group (p < 0.001). After 72 h, the number of cells was highest in the SLActive group exposed once to the LED.


CONCLUSIONS
One LED application in the SLActive group resulted in significantly increased cell numbers. However, these findings were not exactly compatible with the SEM findings, which demonstrated fewer cells and weak attachments between cells and to the surface. Thus, further studies using different LED application times are needed to clarify the reason for the increased number of cells that are apparently incapable of attaching to the titanium surfaces after 72 h.
Department of Oral Surgery, Faculty of Dentistry, Istanbul University, Istanbul, Turkey. cankaya@istanbul.edu.tr
Abdulkadir Burak
AB
Cankaya
Mehmet Ali
MA
Erdem
Arzu Pınar
AP
Erdem
Mine
M
Erguven
Buket
B
Aybar
Cetin
C
Kasapoglu
Ayhan
A
Bilir
D000818:Animals; D002478:Cells, Cultured; D066298:In Vitro Techniques; D008027:Light; D008855:Microscopy, Electron, Scanning; D010006:Osteoblasts / Q000166:cytology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013499:Surface Properties; D014025:Titanium
D014025:Titanium