The Role of Hydrogels in Enhancing Prosthodontic Treatment Outcomes: A Systematic Review

Abstract

Background: This systematic review aims to critically evaluate the evidence on hydrogel-based scaffolds and materials in prosthodontics, compared to traditional acrylic-based treatments. The focus was on outcomes related to mucosal healing, prosthesis retention, bone regeneration, patient satisfaction, and material properties. This review was conducted following PRISMA 2020 guidelines.

Materials and methods: A structured electronic search of PubMed, Scopus, Web of Science, and ScienceDirect was performed for studies published from January 2010 to December 2024. Inclusion criteria were randomized and controlled clinical trials, animal studies, and in vitro investigations examining hydrogel applications in prosthodontics. Two reviewers independently screened studies, extracted data, and assessed quality (using Cochrane RoB 2.0, NOS, SYRCLE, and in vitro checklists). Discrepancies were resolved by consensus. Due to heterogeneity, we conducted a narrative synthesis of findings.

Results: Of 350 records identified, 6 studies met inclusion criteria (2 clinical trials, 2 animal studies, 2 in vitro studies). Clinical trials indicated that hydrogel interventions significantly accelerated mucosal ulcer healing and enhanced implant stability versus controls. An injectable dextrin hydrogel combined with bone grafts yielded higher new bone formation (42.3% vs 35.6%; p = 0.029) and increased implant stability (ISQ 74.5 vs 69.2; p = 0.017) compared to bone graft alone. Animal studies demonstrated robust osteogenesis with hydrogel carriers: for example, a thermo-sensitive alginate hydrogel with BMP-2 achieved 41.6% new bone in defects (vs 12.1% in controls; p < 0.01). In vitro, shape-memory acrylate hydrogels showed mechanical and water sorption properties comparable to PMMA, while chitosan-pectin hydrogel adhesives provided higher initial bond strengths (2.89 kgf vs 1.85 kgf for control; p < 0.01) and superior retention under wet conditions. No study evaluated fully hydrogel-based dentures in humans.

Conclusion: Current evidence suggests hydrogel-based materials may improve tissue healing, preserve alveolar ridge dimensions, and aid immediate prosthesis retention relative to conventional acrylics. However, available studies are limited by small sample sizes, short follow-ups, and focus on adjunctive applications. Well-designed, long-term clinical trials comparing fully hydrogel prostheses to PMMA controls are needed to confirm these advantages.