Application of Reactive Oxygen Species in Dental Treatment

Zerumbone modulates the expression of inflammatory mediators and antioxidant enzymes in TNF-α-stimulated human periodontal ligament cells

OBJECTIVES

Periodontal disease is a chronic inflammatory disease caused by periodontopathogenic bacteria, and its progression leads to periodontal tissue destruction and tooth loss. Zerumbone is a bioactive substance found in ginger (Zingiber zerumbet) and is known to have bioactive effects such as anticancer effects, but there have been no attempts to use it for periodontitis treatment. In addition, there have been no reports examining its effects on periodontal tissue component cells. In this experiment, we aimed to determine whether zerumbone affects the production of inflammatory mediators induced by tumor necrosis factor (TNF)-α in human periodontal ligament cells (HPDLCs), including its effects on signaling pathways.

METHODS

HPDLCs were stimulated by TNF-α (10 ng/ml) with or without zerumbone (6.25, 12.5, or 25 µM). Cytokine production in supernatant was determined using ELISA. Activation of signal transduction pathways and intracellular protein expression were investigated using the western blot analysis.

RESULTS

Zerumbone significantly suppressed TNF-α-induced production of CC chemokine ligand 2 (CCL2), CCL20, CXC chemokine ligand 10 (CXCL10), and interleukin-6 (IL-6) in HPDLCs. In addition, zerumbone decreased intercellular adhesion molecule-1 (ICAM-1) and cyclooxygenase-2 (COX-2) expression in TNF-α-stimulated HPDLCs. Furthermore, zerumbone suppressed activation of nuclear factor (NF)-κB and signal transducer and activator of transcription 3 (STAT3) pathways in TNF-α-treated HPDLCs. Finally, zerumbone enhanced the production of heme oxygenase-1 (HO-1), an antioxidant enzyme, in HPDLCs.

CONCLUSION

These results suggest that zerumbone suppressed the production of several inflammatory mediators by inhibiting the NF-κB and STAT3 pathways in HPDLCs.

Promising potential effects of resveratrol on oral and dental health maintenance: a comprehensive review

Resveratrol (RV-3, 5, 4'-trihydroxystilbene) is a natural compound found in plants like red grapes, berries, and peanuts, with promising effects on dental health. It helps strengthen tooth enamel by promoting remineralization, making the teeth more resistant to decay caused by acid-producing bacteria. RV also shields dentin, a vulnerable layer beneath the enamel, from erosion and sensitivity. Its anti-inflammatory properties can reduce inflammation associated with dental conditions such as pulpitis and endodontic diseases. Moreover, RV's antimicrobial activity inhibits the growth of bacteria involved in dental plaque and biofilm formation, preventing their accumulation on the tooth surface. This contributes to a healthier oral environment and prolongs the lifespan of dental restorative materials. However, the research on RV's impact on dental health is in its early stages, and further studies are needed to confirm potential benefits. Important factors such as determining the optimal dosage, understanding its bioavailability, and assessing potential side effects require further investigation. This review focuses on the important role of RV in promoting dental health. It delves into various aspects, including its impact on root health, maintenance of the dental pulp, care for tooth enamel, effectiveness of dental restorative materials, and health of dentin.

Advancing teeth whitening efficacy via dual-phototherapeutic strategy incorporating molybdenum disulfide embedded in carrageenan hydrogel for dental healthcare

Teeth discoloration poses a widespread challenge in dental health across various regions. Conventional teeth whitening methods often result in enamel deterioration and soft tissue harm due to the utilization of incompatible whitening agents and continuous intense light exposure. Here, we propose an effective phototherapy technique for teeth whitening, employing pathways of energy transition through intersystem crossing. The integration of MoS2 nanosheets into carrageenan gel (MoS2 NSs@Carr) facilitates both photothermal-hyperthermia and the generation of reactive oxygen species (ROS) through photocatalytic processes. The efficacy of ROS generation by the phototherapeutic MoS2 NSs@Carr on teeth whitening in the scenario. This approach ensures comprehensive teeth whitening by eliminating deep-seated stains on the teeth while preserving structural integrity and avoiding any tissue toxicity. This research highlights the efficacy of the phototherapeutic MoS2 NSs@Carr for dental whitening and underscores the potential of exploring nanostructures based on MoS2 NSs for managing dental healthcare issue.

Sonic-assisted antibacterial photodynamic therapy: a strategy for enhancing lateral canal disinfection

BACKGROUND

Bacterial infections in lateral canals pose challenges for root canal treatment. This in vitro study aims to evaluate the antibacterial efficacy of sonic-assisted methylene blue mediated antimicrobial photodynamic therapy (MB-aPDT) against Enterococcus faecalis (E. faecalis) in infected lateral canals.

METHODS

Sixty-five premolars infected with E. faecalis in lateral canals were randomly divided into five groups (n = 13) and treated with : (1) 5.25% NaOCl (positive control); (2) Saline (negative control); (3) Sonic-assisted MB-aPDT; (4) 3% NaOCl + MB-aPDT; (5) 3% NaOCl + sonic-assisted MB-aPDT, respectively. The antibacterial efficacy was evaluated by the colony- counting method (CCM) and scanning electronic microscope (SEM).

RESULTS

Both 5.25% NaOCl and the 3% NaOCl + sonic-assisted MB-aPDT exhibited the most effective while comparable antibacterial effects without significant statistical difference (P > 0.05). Furthermore, the antibacterial effect of the 3% NaOCl + MB-aPDT group was significantly higher compared to that of the sonic-assisted MB-aPDT group (P < 0.05). The SEM results demonstrated notable morphological alterations in E. faecalis across all experimental groups, except for the negative control group.

CONCLUSION

The concentration of NaOCl can be reduced to a safe level while preserving its antibacterial efficacy through the synergism with the sonic-assisted MB-aPDT in this study.

Synthesis of Metallo-Chromone Porphyrin Nano-Starch Sensitizers as Photodynamic Therapeutics for the Eradication of Enterococci Dental Pathogens

Photodynamic therapy (PDT), as an advanced, alternative, and promising treatment, can inhibit dental pathogens. PDT employs the activation of photosensitizers via the light of a particular wavelength and molecular oxygen to inhibit dental pathogens. Herein, we present a comprehensive study on the synthesis and characterization of three chromone-porphyrins [Zn(II)-5-[4-chromone]-15-(4-phenyl)porphyrin (ZnCP), 5-[4-chromone]-15-(4-12 phenyl)porphyrin (DMCP), and Pd(II)-5-[4-chromone]-15-(4-phenyl)porphyrin (PdCP)]. Next, the computational study was also performed to establish the correlation between photophysical properties and theoretical calculations for those chromone-porphyrins using density functional theory and time-dependent density functional theory. Furthermore, chromone-porphyrins were encapsulated in starch nanoparticles to develop soluble nano-starch sensitizers (ZnCP-SNPs, DMCP-SNPs, and PdCP-SNPs) via the nanoprecipitation technique. Upon green light exposure, these nano-starch sensitizers exhibited excellent singlet oxygen generation ability. Moreover, final nanoformulations have been explored for pH responsiveness. Based on our intriguing findings, the chromone-porphyrin-loaded nano-starch sensitizers displayed great potential as prospective PDT to treat enterococci dental pathogens.

An In Vitro Study of Local Oxygen Therapy as Adjunctive Antimicrobial Therapeutic Option for Patients with Periodontitis

Periodontitis is a common global disease caused by bacterial dysbiosis leading to tissue destruction, and it is strongly associated with anaerobic bacterial colonization. Therapeutic strategies such as oxygen therapy have been developed to positively influence the dysbiotic microbiota, and the use of oxygen-releasing substances may offer an added benefit of avoiding systemic effects commonly associated with antibiotics taken orally or hyperbaric oxygen therapy. Therefore, the oxygen release of calcium peroxide (CaO₂) was measured using a dissolved oxygen meter, and CaO₂ solutions were prepared by dissolving autoclaved CaO₂ in sterile filtered and deionized water. The effects of CaO₂ on planktonic bacterial growth and metabolic activity, as well as on biofilms of Streptococcus oralis and Porphyromonas gingivalis, were investigated through experiments conducted under anaerobic conditions. The objective of this study was to investigate the potential of CaO₂ as an antimicrobial agent for the treatment of periodontitis. Results showed that CaO₂ selectively inhibited the growth and viability of P. gingivalis (p < 0.001) but had little effect on S. oralis (p < 0.01), indicating that CaO₂ has the potential to selectively affect both planktonic bacteria and mono-species biofilms of P. gingivalis. The results of this study suggest that CaO₂ could be a promising antimicrobial agent with selective activity for the treatment of periodontitis.

Response of Human Gingival Fibroblasts and Porphyromonas gingivalis to UVC-Activated Titanium Surfaces

Ultraviolet (UV) photofunctionalization has been demonstrated to synergistically improve the osteoblast response and reduce biofilm formation on titanium (Ti) surfaces. However, it remains obscure how photofunctionalization affects soft tissue integration and microbial adhesion on the transmucosal part of a dental implant. This study aimed to investigate the effect of UVC (100–280 nm) pretreatment on the response of human gingival fibroblasts (HGFs) and Porphyromonas gingivalis (P. g.) to Ti-based implant surfaces. The smooth and anodized nano-engineered Ti-based surfaces were triggered by UVC irradiation, respectively. The results showed that both smooth and nano-surfaces acquired super hydrophilicity without structural alteration after UVC photofunctionalization. UVC-activated smooth surfaces enhanced the adhesion and proliferation of HGFs compared to the untreated smooth ones. Regarding the anodized nano-engineered surfaces, UVC pretreatment weakened the fibroblast attachment but had no adverse effects on proliferation and the related gene expression. Additionally, both Ti-based surfaces could effectively inhibit P. g. adhesion after UVC irradiation. Therefore, the UVC photofunctionalization could be more potentially favorable to synergistically improve the fibroblast response and inhibit P. g. adhesion on the smooth Ti-based surfaces.