Dental Implant Macro-Morphology and Surface Characteristics: A Narrative Review

The biological and mechanical stability of dental implants is closely influenced by their macro-morphology, micro- and nano-scale surface topography, and physicochemical surface properties, all of which modulate cell adhesion, osteoblastic activity, and osseointegration. An integrated understanding of the interactions between implant design, surface treatments, and the peri-implant biological response is essential for optimizing clinical outcomes and reducing the risk of complications. This narrative review critically examines the role of implant macro-geometry and the principal surface modification strategies, with particular focus on sandblasted, large-grit, acid-etched (SLA), anodized, nanostructured, and titanium plasma-sprayed (TPS) surfaces, as well as thread geometry and surface roughness. SLA surfaces are widely considered among the most established and extensively investigated implant surface treatments and have been consistently associated with high survival rates and favorable marginal bone level (MBL) stability. Anodized and nanostructured surfaces may offer additional potential benefits in terms of biofunctionalization and antimicrobial activity; however, some evidence suggests slightly lower cumulative survival rates (CSR) and MBL outcomes. Implant macro-geometry, including body shape and thread configuration, plays a critical role in load distribution, primary stability, and bone-to-implant contact (BIC). Overall, available evidence suggests that implant success results from the synergistic interplay between macro-geometry, surface characteristics, and implant-abutment connection design, rather than from a single variable. Moderately rough surfaces combined with optimized implant design appear to represent a well-balanced approach in terms of osseointegration, mechanical stability, and biological safety. Further studies are warranted to better define the optimal parameters of surface roughness, chemical composition, and implant design, and to improve long-term clinical predictability.