Sol-gel synthesis of lithium doped mesoporous bioactive glass nanoparticles and tricalcium silicate for restorative dentistry: Comparative investigation of physico-chemical structure, antibacterial susceptibility and biocompatibility

Abstract

Introduction: The sol-gel method for production of mesoporous bioactive glass nanoparticles (MBGNs) has been adapted to synthesize tricalcium silicate (TCS) particles which, when formulated with other additives, form the gold standard for dentine-pulp complex regeneration. Comparison of TCS and MBGNs obtained by sol-gel method is critical considering the results of the first ever clinical trials of sol-gel BAG as pulpotomy materials in children. Moreover, although lithium (Li) based glass ceramics have been long used as dental prostheses materials, doping of Li ion into MBGNs for targeted dental applications is yet to be investigated. The fact that lithium chloride benefits pulp regeneration in vitro also makes this a worthwhile undertaking. Therefore, this study aimed to synthesize TCS and MBGNs doped with Li by sol-gel method, and perform comparative characterizations of the obtained particles.Methods: TCS particles and MBGNs containing 0%, 5%, 10% and 20% Li were synthesized and particle morphology and chemical structure determined. Powder concentrations of 15mg/10 mL were incubated in artificial saliva (AS), Hank’s balanced saline solution (HBSS) and simulated body fluid (SBF), at 37°C for 28 days and pH evolution and apatite formation, monitored. Bactericidal effects against S. aureus and E. coli, as well as possible cytotoxicity against MG63 cells were also evaluated through turbidity measurements.Results: MBGNs were confirmed to be mesoporous spheres ranging in size from 123 nm to 194 nm, while TCS formed irregular nano-structured agglomerates whose size was generally larger and variable. From ICP-OES data, extremely low Li ion incorporation into MBGNs was detected. All particles had an alkalinizing effect on all immersion media, but TCS elevated pH the most. SBF resulted in apatite formation for all particle types as early as 3 days, but TCS appears to be the only particle to form apatite in AS at a similar period. Although all particles had an effect on both bacteria, this was pronounced for undoped MBGNs. Whereas all particles are biocompatible, MBGNs showed better antimicrobial properties while TCS particles were associated with greater bioactivity.Conclusion: Synergizing these effects in dental biomaterials may be a worthwhile undertaking and realistic data on bioactive compounds targeting dental application may be obtained by varying the immersion media.

Lithium and cobalt co-doped mesoporous bioactive glass nanoparticles promote osteogenesis and angiogenesis in bone regeneration

“…The 29 Si MAS NMR results showed that the incorporation of Li and Co significantly decreased the degree of polymerization and network connectivity of the silicate network of the MBGNs. However, the FTIR spectra showed no significant differences among the four types of MBGNs, which was in agreement with previous studies ( Kargozar et al, 2016 ; El-Fiqi and Kim, 2021 ; Simila and Boccaccini, 2023 ). It is possible that Ca 2+ , Li + , and part of the Co 2+ exist in the silicate network as modifiers, which are ionically linked to nonbridging oxygen atoms, and it is not easy for FTIR to detect the ionic bonds.…”

“…In this study, Li-MBGNs were smaller than uMBGNs, consistent with the results of a previous study ( Simila and Boccaccini, 2023 ); however, explanations for this were not provided. The incorporation of Co 2+ results in nanoparticle agglomeration.…”

Anti‐inflammatory cerium‐containing nano‐scaled mesoporous bioactive glass for promoting regenerative capability of dental pulp cells

“…Consequently, MBGNs are excellent substrates for the loading of various active components, including antibiotics, growth factors (Cheng et al, 2018;Kim et al, 2016) and metal ions such as copper and zinc (Li et al, 2021;Schuhladen et al, 2020), for various treatments. Previous studies have confirmed that MBGNs are suitable for dentine regeneration (Choi et al, 2020;Jung et al, 2019;Simila & Boccaccini, 2023;Zhu et al, 2021). Therefore, we postulated that MBGNs loaded with antiinflammatory Ce ions could serve as a pulp-capping agent for the dentine regeneration.…”

Advances in Nanomaterials and Composites Based on Mesoporous Materials as Antimicrobial Agents: Relevant Applications in Human Health

“…Other ions were evaluated and used in biomedical applications, such as lithium [82], synthesized and characterized the morphology and chemical structure of tricalcium silicate (TCS) and MBGNs doped with 0%, 5%, 10%, and 20% Li using the sol-gel method. Subsequently, concentrations of 15 mg per 10 mL were incubated in artificial saliva, Hank's balanced salt solution, and simulated body fluid at 37 • C for 28 days.…”

“…Bone formation [77] MBGNs/copper ions S. aureus Antibacterial [78] Phosphate-based mesoporous glasses/ Cu ions S. aureus, E. coli Bioabsorbable materials [79] Zn-MBG S. aureus, E. coli Implants-associated infections [80] Zn/SBA-1/SBA-15 E. coli, B. subtilis Bone regeneration [81] Tricalcium silicate/MBGNs/Li S. aureus, E. coli Biomedical applications [82] MBGNs/Ce-Co S. aureus Wound healing [83] Na and colleagues presented an approach against antimicrobial infections by combining antibiotics with photothermal therapy using multifunctional nanomaterials [84]. In this study, the inherent photothermal efficiency of two-dimensional rhenium disulfide (ReS 2 ) nanosheets was heightened by coating them on mesoporous silica nanoparticles (MSNs) to create a highly efficient light-responsive nanomaterial with controlled-release drug delivery capabilities, known as MSN-ReS 2 .…”