Effects of Novel Laser Dental Implant Microtopography on Human Osteoblast Proliferation and Bone Deposition

Purpose: The aim of this study was to compare how two innovative laser titanium surfaces and sandblastedand acid-etched surfaces influence human osteoblast behavior during osteogenesis and the initial phases ofbone deposition. Materials and Methods: Human osteoblasts from human adipose stem cells were sorted byflow cytometric analysis and induced to differentiate. After 40 days, the osteogenic differentiation was detectedby alizarin red staining, and the alkaline phosphatase (ALP) was evaluated with western blot (WB) and real-timereverse transcriptase-polymerase chain reaction (RT-PcR) analysis. After confluence, human osteoblasts werecultured onto two different innovative laser-obtained titanium surfaces (L1 and L2) and compared with onesandblasted and acid-etched (SBAE) surface as the control. At different times, human osteoblast behavior wasevaluated with cell proliferation viability assay (MTT), scanning electron microscopy (SEM), energy-dispersivex-rays (EDAX), osteogenic markers with RT-PcR, and WB analysis of matrix extracellular phosphoglycoprotein(MEPE), ALP, and osteocalcin (OCN). Results: After cell sorting, the human osteoblasts from human adiposestem cells showed increasing values of ALP mRNA and protein expression. The osteogenic differentiation wasconfirmed by quantitative alizarin red staining assay. Profilometric and SEM analysis showed relevant differencesbetween SBAE, L1, and L2 specimens. After 20 days of culture onto titanium samples, SEM evaluation showeda small number of human osteoblasts and isolated sites of bone matrix deposition in SBAE specimens. At thesame time, on L1 surfaces, only an osteoblast mono-layer with initial bone deposition was found, while on L2specimens, there was a thick network with flattened large stellate cells, many cellular interconnections withstrong titanium adhesion, and a large complex mineralized structure of crystal bone. After 20 days, for alltitanium samples, human osteoblasts culturing EDAX analysis showed the absence of impurities and a higherbone matrix deposition in L2 specimens compared with L1 and SBAE samples. Conclusion: The innovativemicrotopography and nanotopography laser-induced surface showed high biocompatibility with primary humanosteoblast cultures and the absence of impurities. The innovative laser texture was capable of influencing theosteogenic process, confirming the critical role of titanium surface characteristics in the cell adhesion andbone deposition during the early phases of osseointegration. The association of human adipose stem cellsand titanium surfaces laser-induced with an innovative procedure could generate promising improvementsand developments in orthopedics, maxillofacial, and dental implant surgery