Graphene-Reinforced Titanium Enhances Soft Tissue Seal

Abstract

The integrity of soft tissue seal is essential for preventing peri-implant infection, mainly induced by established bacterial biofilms around dental implants. Nowadays, graphene is well-known for its potential in biocompatibility and antisepsis. Herein, a new titanium biomaterial containing graphene (Ti-0.125G) was synthesized using the spark plasma sintering (SPS) technique. After material characteristics detection, the subsequent responses of human gingival fibroblasts (HGFs) and multiple oral pathogens (including Streptococci mutans, Fusobacterium nucleatum, and Porphyromonas gingivalis) to the graphene-reinforced sample were assessed, respectively. Also, the dynamic change of the bacterial multispecies volume in biofilms was evaluated using absolute quantification PCR combined with Illumina high-throughput sequencing. Ti-0.125G, in addition to its particularly pronounced inhibitory effect on Porphyromonas gingivalis at 96 h, was broadly effective against multiple pathogens rather than just one strain. The reinforced material’s selective responses were also evaluated by a co-culture model involving HGFs and multiple strains. The results disclosed that the graphene-reinforced samples were highly effective in keeping a balance between the favorable fibroblast responses and the suppressive microbial growth, which could account for the optimal soft tissue seal in the oral cavity. Furthermore, the underlying mechanism regarding new material’s bactericidal property in the current study has been elucidated as the electron transfer, which disturbed the bacterial respiratory chain and resulted in a decrease of microbial viability. According to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, the PICRUSt tool was conducted for the prediction of microbial metabolism functions. Consequently, it is inferred that Ti-0.125G has promising potentials for application in implant dentistry, especially in enhancing the integrity of soft tissue and improving its resistance against bacterial infections around oral implants.

In Vitro Studies of Graphene for Management of Dental Caries and Periodontal Disease: A Concise Review

“…In recent decades, graphene materials were well investigated against periodontal pathogens. In one study, graphene-reinforced titanium was assessed against oral pathogens ( Streptococci mutans , Fusobacterium nucleatum , and Porphyromonas gingivalis ) and reported to have a high inhibitory effect on Porphyromonas gingivalis [ 97 ].…”

“…Studies have well reported that graphene can promote the osteogenic differentiation of several cells, including osteogenic cells and stem cells (bone marrow stem cells, periodontal ligament stem cells, and dental pulp stem cells), and have suggested applying this in different forms (composite, scaffolds, and coatings) [ 134 ]. A study using graphene coating on titanium demonstrated that graphene-titanium can inhibit multiple oral pathogens and enhance human gingival fibroblast growth [ 97 ]. Another study found that single-layer graphene sheets on titanium exhibited excellent adhesion, proliferation, and osteogenic differentiation of human gingival fibroblasts, human adipose-derived stem cells, and human bone marrow mesenchymal stem cells.…”

Fusobacterium nucleatum: The Opportunistic Pathogen of Periodontal and Peri-Implant Diseases

“…Nonetheless, F. nucleatum, which has been fully studied for 20 years regarding the pathogenesis of periodontal diseases, Combats the human immune system and kill lymphocytes has been recently found to be the most abundant species and comprises part of the shared core microbiome of periodontal diseases and peri-implant diseases (Belibasakis and Manoil, 2021). Although there have been many studies using F. nucleatum as an experimental species to investigate antibacterial or material antibacterial subjects (Tonon et al, 2021;Wei et al, 2021), the reason why F. nucleatum is selected seems to be ambiguous. Similarities between periodontal diseases and peri-implant diseases could guide us to pay attention to the relationship between F. nucleatum, periodontal diseases and peri-implant diseases.…”

Customized Barrier Membrane (Titanium Alloy, Poly Ether-Ether Ketone and Unsintered Hydroxyapatite/Poly-l-Lactide) for Guided Bone Regeneration

“…Along with the progress of biomaterials, research for improving the bioactive properties of Ti alloys is advancing ( Liu et al, 2020 ; Wang et al, 2021a ; Wei et al, 2021 ). Xu et al focused on the study of Cu ions with excellent antibacterial properties.…”