Chitosan, a natural polysaccharide sourced from crustaceans and insects, is often used with hydrogels in wound care. Evaluating its cytotoxicity and antimicrobial properties is crucial for its potential use in dentistry. Objective: To investigate the mechanical properties of gelatin hydrogels based on decaethylated chitosan and antimicrobial activity against Streptococcus mutans and their biological effects with stem cells from apical papilla (SCAPs). Material and methods: Gelatin–chitosan hydrogels were synthesized at concentrations of 0%, 0.2% and 0.5%. Enzymatic and hydrolytic degradation, along with swelling capacity, was assessed. Fourier transform infrared spectroscopy (FTIR) analysis was employed to characterize the hydrogels. The interaction between hydrogels and SCAPs was examined through initial adhesion and cell proliferation at 24 and 48 h, using the Thiazolyl Blue Tetrazolium Bromide (MTT assay). The antimicrobial effect was evaluated using agar diffusion and a microdilution test against S. mutans. Uniaxial tensile strength (UTS) was also measured to assess the mechanical properties of the hydrogels. Results: The hydrogels underwent hydrolytic and enzymatic degradation at 30, 220, 300 min and 15, 25, 30 min, respectively. Significantly, (p < 0.01) swelling capacity occurred at 20, 40, 30 min, respectively. Gelatin–chitosan hydrogels’ functional groups were confirmed using vibrational pattern analysis. SCAPs proliferation corresponded to 24 h = 73 ± 2%, 82 ± 2%, 61 ± 6% and 48 h = 83 ± 11%, 86 ± 2%, 44 ± 2%, respectively. The bacterial survival of hydrogel interaction was found to be 96 ± 1%, 17 ± 1.5% (p < 0.01) and 1 ± 0.5% (p < 0.01), respectively. UTS showed enhanced (p < 0.05) mechanical properties with chitosan presence. Conclusion: Gelatin–chitosan hydrogels displayed favorable degradation, swelling capacity, mild dose-dependent cytotoxicity, significant proliferation with stem cells from apical papilla (SCAPs), substantial antimicrobial effects against S. mutans and enhanced mechanical properties. These findings highlight their potential applications as postoperative care dressings.

Nanomaterials have displayed vast potential across a spectrum of biomedical applications, particularly in recent studies aimed at optimizing traditional systems. Metal oxide nanoparticles, like Magnetic nanoparticles (MNPs), offer unique physicochemical properties ideal for biomedical applications, advancing diagnostics, therapies, tissue engineering and imaging technologies in medicine. Their notable features, such as high specific surface area and porous structure, render them versatile for myriad medical and biological uses. When combined with polymers, MNPs have found utility in nano‐scale treatments targeting specific human ailments, encompassing drug delivery, tissue engineering, and wound care. This review focuses on summarizing the utilization of MNPs examining their structural attributes, magnetic properties, biocompatibility, and their role in scaffolding applications. Furthermore, within the dental domain, periodontitis presents substantial challenges, prompting research into regenerative therapies to foster the growth and specialization of key cell types crucial for effective disease management and tissue revitalization.

The use of magnetic materials, such as ferrofluids, is of great importance in biomedical applications, and as a result, interest in studying their magneto-optical properties has grown significantly in recent years. Therefore, in this work, magnetic nanoparticles were synthesized with chitosan coating, leaving the product as a ferrofluid in aqueous solution. Structural, morphological, magnetic, and optical characterization was carried out obtaining a cubic structure centered on the faces, a spherical morphology with a size distribution of 10–14 nm according to TEM images and a magnetic saturation of 53 emu/g. In the optical properties, the effect of chitosan shell on the forbidden band was studied, showing a blue-shifting effect, due to reduction on the inner magnetic nanoparticles size.

Orthodontic adhesives can accumulate biofilm, which may lead to long-term white-spot lesions; however, incorporating poly (lactic-co-glycolic acid) (PLGA) nanoparticles could improve their anticariogenic properties. Objective: To develop PLGA nanoparticles containing antiseptic agents for orthodontic adhesives, improve antibacterial activity against Streptococcus mutans, and assess cytotoxicity in gingival fibroblasts. Methods: PLGA nanoparticles with chlorhexidine and chitosan were synthesized and characterized using FTIR, SEM, and UV-Vis spectroscopy. Antibacterial activity was evaluated by agar diffusion and microdilution assays, and cytotoxicity and microhardness were also assessed. Results: PLGA-NPs showed moderate antibacterial effects, with inhibition rates from 74.25% to 54.05% in agar diffusion and reduced activity in microdilution (CC50: 3.75 µg/mL in adhesive, 15 µg/mL free). PLGA-NPs-CHx exhibited stronger antibacterial activity, with inhibition ranging from 89.38% to 73.75% and a CC50 of 0.93 µg/mL in both forms. PLGA-NPs-CH also showed significant inhibition (83.11% to 69.39%) and a CC50 of 1.87 µg/mL in adhesive and 7.5 µg/mL free. Vickers microhardness values were similar across groups: 74.67 HV for adhesive only, 74.11 HV for adhesive with PLGA-NPs, 74.22 HV for PLGA-NPs-CH-Adh, and 74 HV for PLGA-NPs-CHx-Adh. Conclusions: Incorporating PLGA nanoparticles functionalized with antiseptic agents into orthodontic adhesives shows promising antibacterial potential and may benefit orthodontic practice.