Effects of Surface Treatment Method Forming New Nano/Micro Hierarchical Structures on Attachment and Proliferation of Osteoblast-like Cells

Abstract

Titanium (Ti) and Ti-based alloys are commonly used in dental implants, and surface modifications of dental implants are important for achieving osseointegration (i.e., direct connection between the implant surface and bone). This study investigated the effect of an eco-friendly etching solution—a hydrogen peroxide–sodium bicarbonate mixture—on the surface properties and contact angles of osteoblast adhesion and proliferation on Ti surfaces. Disk-shaped Ti specimens were prepared using different surface treatments (machining, sandblasting, and sandblasting/acid-etching), and they were immersed in the etching solution and ultrasonically cleaned. Surface characterization was performed using scanning electron microscopy, digital microscopy, contact angle analysis, and X-ray photoelectron spectroscopy. MG-63 osteoblasts were cultured on the specimens, and their adhesion to the specimen surface and proliferation were examined using staining and the MTT assay, respectively. Additional etching with the etching solution caused the formation of nano/micro hierarchical structures, increased surface roughness, and enhanced hydrophilicity. Osteoblast adhesion and proliferation were found to improve on the modified surfaces. The eco-friendly etching method has the potential to enhance the biological properties of Ti implant surfaces and thereby improve dental implant performance.

Construction of functional surfaces for dental implants to enhance osseointegration

“…Sand-blasted, large-grit, and acid-etched (SLA) technique has emerged as the most commercially successful Ti-based dental implant, which was introduced in 1997. It is a process that involves blasting with coarse abrasive particles followed by acid-etching ( Im et al, 2023 ). SLA generates a topographical surface that exhibits isotropic characteristics.…”

“…This topography consists of macro-scale irregularities, as well as interconnected cavities at the micro-scale and submicro-scale levels ( Kim et al, 2013 ). The greater osseointegration is believed to be attributed to several factors, including improved mechanical interlocking with the adjacent bone, increased surface area, surface energy, protein adsorption, and cell adhesion during the initial stages of wound healing ( Im et al, 2023 ). Instead of the conventional dual etching solutions consisting of sulphuric and hydrochloric acids used in SLA, Jae-Seung Im et al used an eco-friendly hydrogen peroxide (H 2 O 2 )/sodium bicarbonate (NaHCO 3 ) mixture for etching.…”

“…Instead of the conventional dual etching solutions consisting of sulphuric and hydrochloric acids used in SLA, Jae-Seung Im et al used an eco-friendly hydrogen peroxide (H 2 O 2 )/sodium bicarbonate (NaHCO 3 ) mixture for etching. Osteoblast adhesion and proliferation were enhanced on the modified SLA surfaces ( Im et al, 2023 ).…”

Improved Biocompatibility and Osseointegration of Nanostructured Calcium-Incorporated Titanium Implant Surface Treatment (XPEED®)

“…Surface roughness can be classified into macroscale, microscale, and nanoscale surface types [ 10 ]. Studies investigating initial fixation and mechanical aspects of implant stability with different surfaces have shown that surfaces with moderate roughness perform better than smooth surfaces [ 11 ]. Implant surfaces with a nanoscale size exhibit superior protein adsorption and enhance osteoblast attachment and proliferation, contributing to early osseointegration [ 11 ].…”

“…Studies investigating initial fixation and mechanical aspects of implant stability with different surfaces have shown that surfaces with moderate roughness perform better than smooth surfaces [ 11 ]. Implant surfaces with a nanoscale size exhibit superior protein adsorption and enhance osteoblast attachment and proliferation, contributing to early osseointegration [ 11 ]. Implant surface roughness ranges from 1 to 23 μm, and measurement methods usually have an accuracy of less than 1 μm [ 12 , 13 , 14 , 15 ].…”