The surface-agnostic advantage for peri-implant health: UV photofunctionalization as a positive-sum strategy for biofilm suppression and soft-tissue barrier—a systematic review with qualitative synthesis

PURPOSE: Long-term dental implant success depends on a biologic "race to the surface," in which osteogenic cells, peri-implant soft-tissue cells, and bacterial pathogens compete for early dominance at the implant-tissue interface. Because implant surface design is often optimized for one objective at the expense of another (e.g., micro-roughness to accelerate osteoconductivity but with increased plaque-retention risk; relatively smooth transmucosal surfaces to discourage bacterial attachment despite uncertainty regarding optimal soft-tissue integration), strategies that enhance peri-implant health without forcing topographical trade-offs are needed. Ultraviolet (UV) photofunctionalization-by removing storage-acquired hydrocarbons ("biological aging") and converting surfaces to a high-energy, superhydrophilic state-has been proposed as a chairside, topography-preserving approach to improve interfacial biology. This systematic review evaluates whether UV photofunctionalization of titanium and zirconia surfaces provides clinically relevant advantages for (1) reduction of bacterial attachment and biofilm formation, (2) peri-implant soft-tissue responses relevant to mucosal sealing, and (3) human clinical outcomes. METHODS: After systematic literature search, screening and full-text evaluation, a total of 34 articles, including 9 bacterial/biofilm, 13 soft-tissue (1 overlapping between bacterial and soft-tissue), and 13 clinical studies were selected. Findings were synthesized qualitatively with attention to protocol heterogeneity (UV wavelength band, exposure duration, device configuration, and material and surface types). RESULTS: Across experimental models, UV photofunctionalization most consistently reduced early bacterial attachment and/or early biofilm accumulation across several titanium surface topographies, supporting an early anti-adhesive and biofilm-suppressive phenotype. Soft-tissue studies generally demonstrated enhanced fibroblast/epithelial attachment, spreading, and functional behaviors relevant to sealing on both titanium and zirconia, although the optimal underlying topography for soft-tissue integration remains unresolved. Clinically, the most consistent signal was accelerated and enhanced implant stability development, while selected studies also suggested favorable trends in peri-implant soft-tissue parameters and/or crestal bone maintenance. However, clinical outcomes remained variable and were limited by heterogeneity in UV protocols, surface systems, endpoints, and follow-up duration. CONCLUSIONS: UV photofunctionalization can be conceptualized as a surface-agnostic physicochemical reactivation technology: a topography-preserving enhancement that restores high surface energy and favorable surface chemistry without altering the underlying surface architecture. Current evidence for this concept is strongest for titanium, whereas supportive evidence for zirconia is emerging primarily from soft-tissue and interface-focused models. This interface-first, positive-sum strategy may allow clinicians to select zone-specific topographies (e.g., smooth transmucosal regions and rough endosteal regions) while maximizing soft-tissue affinity and suppressing early colonization. Although current clinical evidence most strongly supports accelerated osseointegration/stability development, further longitudinal studies with standardized peri-implant health, microbiologic, and mucosal inflammatory endpoints are needed to clarify the long-term translational impact of UV photofunctionalization on peri-implant disease prevention.