Hyaluronic Acid as an Adjunct in Bone Regeneration—A Systematic Review

Background: Bone tissue is a dynamic structure capable of continuous remodeling; however, its regenerative capacity is limited in critical-size defects, often requiring the use of bone grafting procedures. Available grafting materials present inherent limitations, highlighting the need for strategies that can enhance regenerative outcomes. Hyaluronic acid (HA) has been proposed as a promising adjunctive agent because of its biological properties, including anti-inflammatory and pro-angiogenic effects. Objective: To systematically evaluate the available clinical evidence regarding the effects of HA as an adjunct in bone regeneration procedures, including alveolar ridge preservation, ridge augmentation, and maxillary sinus elevation. Materials and Methods: A systematic search was conducted in the PubMed, ScienceDirect, Google Scholar, and Wiley Online Library databases for studies published within the last 10 years. Clinical studies involving adult patients were included if they evaluated the local application of HA, regardless of formulation, and reported quantitative clinical, radiographic, histological, or histomorphometric outcomes related to bone regeneration. Results: Of the 728 records initially identified, 10 studies met the eligibility criteria and were included in the qualitative synthesis. Discussion: Overall, the available evidence suggests that HA may positively influence bone regeneration outcomes. The most consistent benefits were observed in alveolar ridge preservation and ridge augmentation procedures, including increased new bone formation, improved bone density, enhanced bone maturation, and reduced dimensional bone loss. In contrast, findings regarding maxillary sinus augmentation were less consistent. Conclusions: HA appears to be a promising adjunct in bone regeneration procedures. However, the current evidence remains limited and is primarily based on clinical outcomes, providing insufficient mechanistic data to fully elucidate its biological effects. Further well-designed randomized controlled trials with standardized protocols are required before definitive clinical recommendations can be established.