Laser Ablated Titanium Implants Tested by MG63 Osteoblast Cell Culture

Objectives: The demand is increasing to speed up the otherwise long osseointegration period (3-6 months) to rehabilitate the damaged chewing apparatus of the patients as soon as possible. For dental implants, likewise to biomaterials, bio- and osseointegration processes can be controlled at molecular and cellular level by modification of implant surface. One of the most promising surface modifications that could enhance osseointegration of dental implants is laser ablation, as proven by our previous results. Methods: Commercially pure (CP4) sandblasted and acid etched titanium discs (Denti® System Ltd. Hungary) were irradiated with a KrF excimer laser (248 nm, 0.4J/cm2 fluence, FWHM=18 ns, 2000 pulses), or with green laser (532 nm, 40 mJ, FWHM=10 ns, 1.3J/cm2 fluence, 200 pulses). The discs were examined by SEM, AFM and XPS. In vitro cell culture testing was performed with MG63 osteoblast-like cells. Attachment (24h) and proliferation (72h observation) of these cells were investigated via dimethylthiazol-diphenyl tetrazolium bromide (MTT) and Alamar Blue (AB) assays. Results: SEM and AFM revealed significant morphological and roughness changes for the treated samples. XPS confirmed the presence of TiO2 on each sample, but on the samples treated with green laser a more reduced state of Ti was also observed. MTT measurements proved that the amount of cells was increased three times after 72h compared to 24h observation, while AB measurements showed that the number of cells was doubled. Cell attachment and proliferation was significantly enhanced on the laser treated samples with respect to the control samples, revealed by MTT experiments. Conclusions: Laser treatment and especially the excimer laser ablation led to a significant increase in the attachment and proliferation of MG63 osteoblast-like cells. This method may effectively accelerate osseointegration of titanium implants. Acknowledgments: Supported by the ETT project (434/2006) of the Hungarian Ministry of Health and OTKA (K67818).