Bioactive restorative materials represent a paradigm shift in modern dentistry, moving from passive restorations to functional materials that actively promote oral health. This review comprehensively explores the evolution, mechanisms of action, methods of assessment, and clinical applications of direct bioactive restorative materials, including glass ionomer cements (GICs), resin-based composites, and ion-releasing materials. This review critically analyzes their roles in remineralization, fluoride release, antimicrobial activity, and tissue regeneration, while also addressing their mechanical properties and limitations. A systematic literature search was conducted across major databases, including PubMed, Scopus, Web of Science, and ScienceDirect. Key findings reveal that bioactive GICs, resin-based composites, and ion-releasing materials exhibit varying degrees of bioactivity through ion release, apatite layer formation, and collagen interaction. Recent advances in calcium phosphate-based fillers, bioactive glass additives, and antimicrobial agents have significantly improved these materials’ therapeutic potential. However, challenges remain regarding mechanical strength, long-term stability, and standardization of bioactivity assessment. Future research should focus on developing standardized testing protocols, optimizing mechanical performance, and conducting rigorous long-term clinical trials to fully harness the potential of bioactive restorative materials in dental practice. Also identifying the key knowledge gaps and proposing future research directions to advance the field.

Denture base fabrication has advanced with the introduction of computer-aided design and manufacturing (CAD-CAM) techniques, such as subtractive milling and additive 3D printing. However, concerns persist regarding the mechanical performance of 3D-printed denture bases. This systematic review and meta-analysis aimed to evaluate and compare the flexural strength (FS), surface hardness, fracture toughness, and impact strength of 3D-printed denture bases with those produced by milling and conventional methods. A systematic search of PubMed, Scopus, Web of Science, and Cochrane Central was conducted up to March 2025 in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. In vitro studies comparing 3D-printed denture bases with milled or conventional heat-polymerized bases in terms of mechanical properties were included. The Joanna Briggs Institute (JBI) checklist for quasi-experimental studies was used. Data was extracted, and quantitative synthesis was performed where possible. Thirty-eight studies were included, comprising 562 specimens for FS and 231 for surface hardness. Meta-analysis revealed that milled denture bases demonstrated the highest flexural strength (MD = -1.11, 95% CI [-1.29, -0.93], p < 0.001) and surface hardness (MD = -26.49, 95% CI [-29.89, -23.10], p < 0.001) compared to 3D-printed bases. Conventional bases outperformed 3D-printed ones in most mechanical properties. Milled denture bases exhibited the highest FS (120–146 MPa), followed by conventional PMMA (95–119 MPa), while 3D-printed bases showed wider variability (28–128 MPa). Surface hardness (VHN), fracture toughness (MPa·m¹/²), and impact strength (kJ/m²) were also superior in milled bases. Statistical heterogeneity was present due to differences in materials, printing orientation, and post-curing protocols. Subgroup analysis based on printing orientation (0°, 45°, and 90°) partially explained this variability, showing higher FS in horizontally printed specimens. Although 3D-printed denture bases offer customization and production efficiency, their mechanical properties remain inferior to milled alternatives. Optimization of resin formulations, printing parameters, and post-processing protocols is essential to enhance their clinical performance. The main limitations were high heterogeneity among included studies, differences in material formulations, variability in testing standards, and the in vitro nature of most included studies. This review was registered in PROSPERO (CRD420250639092). There were no deviations from the registered protocol.

The purpose of this study is to systematically review the effect of printing layer thickness and build orientation on the marginal and internal fit of 3D-printed fixed dental prostheses (FDPs). A systematic search was conducted in PubMed, Scopus, Web of Science, and Cochrane Library up to August 2025 following PRISMA guidelines (PROSPERO: CRD42024591005). Comparative studies assessing the impact of layer thickness on marginal gap (MG), internal gap (IG), or absolute marginal discrepancy (AMD) of 3D-printed FDPs and crowns were included. Risk of bias was assessed using a modified CONSORT tool. Thirteen in vitro studies met the eligibility criteria. Thinner layers (20–50 μm), particularly at 50 μm, improved marginal and internal fit compared to thicker layers (100 μm). Intermediate build orientations (45°–60°) minimized discrepancies, while extreme orientations (0° and 90°) increased stair-stepping effects. Marginal gap values generally ranged from 40 to 120 μm, within clinical acceptability. Subtractive (milled) restorations consistently showed superior fit compared to additive manufacturing. Layer thickness and build orientation significantly influence the fit of 3D-printed FDPs. A layer thickness of 50 μm at intermediate build orientations (45°–60°) provides the best adaptation. Milling remains the gold standard for precision, although optimized 3D-printing parameters can achieve clinically acceptable accuracy. Optimizing 3D-printing parameters—especially using 50 μm layer thickness with intermediate build orientations—enhances the marginal and internal precision of FDPs. While 3D printing is suitable for provisional restorations, milled prostheses remain preferable for definitive restorations requiring the highest accuracy.

Glass ionomer cement (GIC) is valued in restorative dentistry for its chemical adhesion, fluoride release, and biocompatibility but has limitations in mechanical strength and long-term antibacterial activity. Propolis, a natural resin rich in flavonoids and phenolic acids, has shown antimicrobial, antioxidant, and anti-inflammatory effects, making it a potential bioactive additive to improve GIC performance. This systematic review evaluates the effects of propolis-modified GIC on antimicrobial activity and physico-mechanical properties, while identifying optimal formulations and concentrations for clinical use. Special emphasis is placed on methodological heterogeneity, chemical characterization gaps, and future research needs. Publications up to the end of 2024 were included from the Cochrane Library, Web of Science, PubMed, and Scopus. The review was registered on PROSPERO (CRD42024627498) and conducted according to PRISMA guidelines using the PICO framework. Propolis-modified GIC generally demonstrated enhanced antibacterial activity against Streptococcus mutans , Lactobacillus , and Candida albicans , particularly at concentrations of 25–50%. Mechanical outcomes varied with concentration, with 25% often balancing antimicrobial efficacy and mechanical stability, while higher concentrations improved hardness but sometimes reduced compressive and bond strength. Considerable heterogeneity was observed in GIC brands, propolis sources, extraction techniques, and incorporation methods, limiting direct comparability. Most studies lacked detailed chemical characterization, making it unclear which flavonoids or phenolic compounds drive the observed effects. Yellow discoloration was the main reported esthetic change, with no studies assessing long-term color stability or translucency. Propolis-modified GIC is a promising bioactive restorative material with potential antimicrobial benefits. However, methodological weaknesses, heterogeneity in preparation, and absence of chemical and long-term esthetic evaluation limit the direct clinical applicability of current evidence. Standardized protocols for material preparation, bioactive component identification, and comprehensive testing of mechanical and esthetic properties are recommended to advance this field.

Aims: This systematic review critically evaluates the antimicrobial performance, mechanical properties, and fluoride release of glass ionomer cements (GICs) modified exclusively with green-synthesized nanoparticles. The review highlights how eco-friendly nanoparticle production influences material behavior and clinical applicability. Methods: A comprehensive literature search was conducted across multiple electronic databases to identify in vitro, in vivo, and clinical studies reporting on GICs incorporated with green synthesized nanoparticles. Inclusion criteria were based on nanoparticle synthesis method, outcomes, and material characterization. Data extraction, quality assessment, and synthesis followed PRISMA guidelines. Results: Twenty-five studies met the inclusion criteria. Green-synthesized nanoparticles derived from plant and biological extracts consistently enhanced antibacterial activity through reactive oxygen species (ROS) generation, membrane disruption, ion release, and biofilm inhibition. Improvements in compressive strength, microhardness, and fluoride release were observed for several nanoparticle formulations, particularly chitosan–titania–zirconia–hydroxyapatite and plant-mediated hydroxyapatite. However, variability in synthesis routes, nanoparticle concentrations, and characterization protocols limited direct comparison across studies. Conclusions: Green-synthesized nanoparticles significantly improve the antimicrobial and mechanical properties of GICs while offering enhanced biocompatibility and sustainability compared to chemically synthesized nanomaterials. Standardized synthesis, precise nanoparticle characterization, and clinical validation are essential to advance the integration of green nanotechnology in restorative dentistry.