# Evolving Strategies and Materials for Scaffold Development in Regenerative Dentistry
## 4 Discussion
### Materials for Scaffold Fabrication in Regenerative Dentistry  
Scaffolds are generally considered as supporting pillars for stem cells that are to be grown. They can be fabricated from different materials, including biomaterials or their combinations. Material selection is crucial for proper in vivo functioning. A significant progress in scaffold fabrication from biocompatible materials has been made over the past years, presenting properties that allow them to become alternatives for conventional grafts. The selection of materials (including nanomaterials) [72; 107; 108] determines properties of scaffolds. The aim usually is to get as close as possible to native tissue characteristics. Scaffolds themselves influence the properties, behavior, growth, and functioning of stem cells seeded within [109]. The range of use of biomaterials in regenerative dentistry keeps increasing. Biomaterials can enhance cell proliferation rates, viability. They can modify responses of cells, increase their surface adhesion, differentiation, osteoblastic and odontoblastic activity, osteoconductivity, mineralization processes, antimicrobial effects, vascularization, and other mechanical and biological functions. These numerous effects determine the applications of biomaterials in regenerative dentistry [110, 111, 112, 113]. In fact, biomaterials in the form of scaffolds have shown favorable properties in restorative dentistry, endodontics, implantable, and maxillofacial surgery [114, 115, 110]. Graphene-based scaffolds offer biocompatibility, anti-bacterial properties, and the ability to stimulate cellular processes. This makes them promising for tissue engineering, though further research on potential cytotoxicity is needed [32, 116]. The applications of chitosan were also explored in several studies [34, 40, 111, 113, 117]. It was concluded that chitosan itself has poor mechanical properties, undergoes rapid degradation, and has limited use due to rather low osteoconductivity [40, 118, 119]. Therefore, chitosan and graphene oxide were combined with hydroxyapatite and xanthan gum to form Chitosan/Xanthan/Hydroxyapatite-Graphene Oxide scaffold, which has enhanced biological properties and high cell viability in a MTT cytotoxicity test [117]. [PERSON] et al., combined chitosan nanofibers with nano-hydroxyapatite particles, resulting in high antibacterial and antibiofilm effects against _P. gingivalis_[111]. [PERSON] et al. discovered that Ce\({}^{3+}\)-doped fluorapatite integrated into chitosan scaffolds increases osteoconductivity levels, enhances osteogenic differentiation, and boosts antibacterial activity more compared to the Sr\({}^{2+}\)-doped fluorapatite-chitosan scaffold when assessed with dental pulp stem cells (DPSCs) [113]. DPSCs also improved their cell proliferation rates when gelatine as a co-polymer was added into the chitosan-based scaffold [120]. Other researchers developed fibrin-based hydrogels supplemented with chitosan nanoparticles for dental pulp regeneration purposes, which also showed good antimicrobial activity against highly resistant _E. faecalis_ often located in infected root canals [121, 122, 123, 124]. In addition, fibrin-chitosan hydrogel did not have negative effects on dental pulp cell viability, proliferation, morphology, and collagen production [34]. Furthermore, the study from [PERSON] et al. explored gyroid and rectilinear 3D-printed hydroxyapatite scaffolds made from novel composite filament, which were sintered at 1300 \({}^{\circ}\)C and 1400 \({}^{\circ}\)C with high biocompatibility and in vitro cell adhesion [112]. [PERSON] et al. presented alginate as a material with high potential in regenerative endodontics due to its wide spectrum of applications. Besides being used in a form of scaffold, alginate can be a cell-carrier, a microcapsule delivery agent, an agent used for boosting chelating properties of hypochlorite, and a root canal sealer [125].