Abstract
The long-term stability of dental implants depends on high-quality osseointegration, and implant surface topography is regarded as one of the most critical and controllable determinants. Sandblasted, large-grit, acid-etched (SLA) surfaces have been widely adopted in clinical practice; however, the differences between a conventional single-scale micro rough topography and hierarchical architectures created by superimposing nanoscale features on this micro rough base, particularly with respect to osteogenesis and osteoimmunity, have not yet been systematically reviewed. Against this background, the present review focuses on the influence of SLA surface topographical characteristics on osseointegration, and summarizes recent advances regarding SLA and its micro/submicron- and micro/nanoscale hierarchical structures in regulating osteogenic cell behavior and macrophage responses. Conventional SLA surfaces typically exhibit a moderately micro rough topography, with Sa values of approximately 1–2μm. Building additional submicron or nanoscale features on this micro rough base further increases surface area and morphological complexity, while largely maintaining cell proliferative activity and enhancing cell adhesion, osteogenic differentiation, and mineralization. Emerging evidence also indicates that such hierarchical structures can amplify pro-osteogenic signaling by activating pathways involving autophagy and exosomes, and, in some designs, confer additional antibacterial effects, thereby accelerating osseointegration through the synergistic contributions of microscale mechanical interlocking, nanoscale cell stimulation, and osteoimmunity modulation.
Keywords: dental implants, sandblasted, large-grit, acid-etched (SLA), surface topography, micro-Nano-hierarchical structures, osteogenesis, osteoimmunology
