Osteoblastic Cell Behavior and Gene Expression Related to Bone Metabolism on Different Titanium Surfaces

Abstract

The surface topography of titanium dental implants has a great influence on osseointegration. In this work, we try to determine the osteoblastic behavior and gene expression of cells with different titanium surfaces and relate them to the physicochemical properties of the surface. For this purpose, we have used commercial titanium discs of grade 3: as-received corresponds to machined titanium without any surface treatment (MA), chemically acid etched (AE), treated via sand blasting with Al2O3 particles (SB) and a sand-blasting treatment with acid etching (SB+AE). The surfaces have been observed using scanning electron microscopy (SEM) and the roughness, wettability and surface energy with dispersive and polar components have been characterized. Osteoblastic cultures were performed with SaOS-2 osteoblastic cells determining cell viability as well as alkaline phosphatase levels for 3 and 21 days, and osteoblastic gene expression was determined. The roughness values of the MA discs was 0.02 μm, which increases to 0.3 μm with acid attack and becomes the maximum for the sand-blasted samples, reaching values of 1.2 μm for SB and SB+AE. The hydrophilic behavior of the MA and AE samples with contact angles of 63° and 65° is superior to that of the rougher samples, being 75° for SB and 82° for SB+AE. In all cases, they show good hydrophilicity. GB and GB+AE surfaces present a higher polar component in the surface energy values, 11.96 and 13.18 mJ/m2, respectively, than AE and MA, 6.64 and 9.79 mJ/m2, respectively. The osteoblastic cell viability values at three days do not show statistically significant differences between the four surfaces. However, the viability of the SB and SB+AE surfaces at 21 days is much higher than that of the AE and MA samples. From the alkaline phosphatase studies, higher values were observed for those treated with sand blasting with and without acid etching compared to the other two surfaces, indicating a greater activity in osteoblastic differentiation. In all cases except in the Osterix (Ostx) —osteoblast-specific transcription factor—a decrease in gene expression is observed in relation to the MA samples (control). The most important increase was observed for the SB+AE condition. A decrease in the gene expression of Osteoprotegerine (OPG), Runt-related transcription factor 2 (Runx2), Receptor Activator of NF-κB Ligand (RANKL) and Alkaline Phosphatase (Alp) genes was observed in the AE surface.

Osteoblast Attachment on Bioactive Glass Air Particle Abrasion-Induced Calcium Phosphate Coating

“…The surface roughness influences the proliferation and differentiation of osteoblastic cells [44]. Macro-and micro-surface roughness produced by the SA process has led to higher osteoblast activity than on machined surfaces [45]. However, Cho et al [46] reported somehow contradicting results that the osteoblast cell proliferation rate was slightly higher on machined compared to SA surface.…”

Comparative Analysis of Osteoblastic Responses to Titanium and Alumina-Toughened Zirconia Implants: An In Vitro Study

“…In the next step, all samples were dehydrated with ethanol at different percentages and placed in the environment to dry the solvents completely. Then the samples were analyzed with the SEM [ 19 ].…”

The Effect of Implantoplasty on the Fatigue Behavior and Corrosion Resistance in Titanium Dental Implants

“…One hundred twenty implants were tested at 25 °C under dry conditions (n = 30) and in Hank's solution at 37 °C (n = 30) for control and treated by implantoplasty. The chemical composition of Hank s solution (ThermoFisher, Madrid, Spain) is shown in Table 1 [28][29][30]. The dental implants control and after of the implantoplasty procedure can be observed in Figure 3.…”