Efficacy of curcumin-mediated photodynamic therapy for root canal therapy procedures: A systematic review

SWEEPS-Assisted Antibacterial Photodynamic Therapy Against Dual-Species Biofilms in Mandibular Molars: An In Vitro Study

Objectives: The synergistic effect of shock wave-enhanced emission photoacoustic streaming (SWEEPS) and antimicrobial photodynamic therapy (aPDT) in mandibular molar root canal disinfection remains underexplored, particularly against dual-species biofilms that better simulate clinical conditions. This study evaluates their combined antimicrobial efficacy against Enterococcus faecalis and Candida albicans biofilms and assesses potential tooth discoloration caused by riboflavin and nano-curcumin. Materials and Methods: The mesiobuccal canals of 57 extracted mandibular molars were inoculated with E. faecalis and C. albicans biofilms. The antimicrobial effects were assessed using riboflavin or nano-curcumin with a 450 nm diode laser (BDL), SWEEPS, or their combinations, compared to 5.25% NaOCl (positive control) and saline (negative control). Biofilm reduction was quantified by colony-forming units (CFUs/mL), and discoloration was evaluated using the ΔE metric in the CIE L*a*b* color space. Results: Both microorganisms showed a significant decrease in colony numbers in all experimental groups compared to the negative control (p < 0.001), except for E. faecalis, where no significant difference was observed between the riboflavin/nano-curcumin groups and the negative control. Combining riboflavin or nano-curcumin with SWEEPS or BDL significantly enhanced antimicrobial efficacy compared to individual treatments (p < 0.001). The combined photodynamic therapy and SWEEPS groups showed the lowest colony counts. The ΔE values were, on average, 1.81 for riboflavin and 1.09 for nano-curcumin. Conclusions: The combination of SWEEPS and aPDT effectively reduces E. faecalis and C. albicans biofilms in molars, supporting its potential as an adjunct in endodontic disinfection. Minimal discoloration further highlights its clinical applicability.

In vitro evaluation of antimicrobial photodynamic therapy with photosensitizers and calcium hydroxide on bond strength, chemical composition, and sealing of glass-fiber posts to root dentin

Investigate the impact of antimicrobial photodynamic therapy (aPDT) using different photosensitizers (PSs) such as indocyanine green (IG), curcumin (CC), and methylene blue (MB), with or without intracanal application of calcium hydroxide (CH), on the push-out bond strength of glass-fiber posts (GFPs) to intraradicular dentin, the chemical composition of the root substrate, and the sealing of the adhesive interface across different thirds of intraradicular dentin. A total of 112 bovine teeth underwent biomechanical preparation and were divided into eight experimental groups (n = 14 each): Negative control with deionized water; positive control with deionized water + CH; IG group with indocyanine green and infrared laser; IG + CH group; CC group with curcumin and blue LED; CC + CH group; MB group with methylene blue and red laser; and MB + CH group. The push-out bond strength was measured using a universal testing machine (n = 8), and scanning electron microscopy characterized the fracture patterns. Energy dispersive spectroscopy (n = 3) analyzed the chemical composition of the dentin substrate, while fluorescence confocal microscopy (n = 3) assessed the adhesive interface sealing between the resin cement and root dentin. Data were analyzed using two-way repeated measures ANOVA and the Tukey test for push-out bond strength and chemical composition comparison, with the Kruskal-Wallis and Dunn's tests (α = 0.05) for adhesive interface sealing. Significant bond strength differences were noted across root thirds and experimental groups (P < .05), with the IG + CH group showing the highest cervical bond strength and the IG group the lowest. Apical bond strength was highest in the CC group but lower in the NC and PC groups. Mixed failures predominated, except in the MB + CH group, where adhesive failures prevailed. Elemental composition varied among groups treated with different PSs and CH (P < .05), but interface quality, tag formation, and penetration depth showed no significant differences (P > .05). Laser-activated 500 mg/L CC combined with CH emerged as a clinically relevant option for root canal decontamination before GFPs luting. aPDT with different PSs and root canal depth influenced the push-out bond strength of GFPs and the chemical composition of root dentin. Curcumin-mediated aPDT at 500 mg/L proved effective, enhancing bond strength and sealing while maintaining consistent dentin composition across depths.

A curcumin-based HDACs inhibitor for targeted sonodynamic therapy of breast cancer

Histone Deacetylases (HDACs) have emerged as key therapeutic targets in cancer treatment. In this study, we designed CURSAHA, a multifunctional anticancer agent, through the pharmacophore fusion of Vorinostat and curcumin. CURSAHA demonstrates broad-spectrum inhibitory activity against HDACs, effectively suppressing tumor cells with overexpressed HDACs. Notably, CURSAHA generates reactive oxygen species (ROS) under ultrasonic conditions, exhibiting sonodynamic therapeutic activity. Additionally, CURSAHA downregulates HDACs through redox reactions involving ROS. These properties enable CURSAHA to exhibit robust antitumor activity in both in vitro and in vivo models, highlighting its potential as a promising candidate for further development in cancer therapy.

A Review of the Efficacy of Nanomaterial-Based Natural Photosensitizers to Overcome Multidrug Resistance in Cancer

Natural photosensitizers (PS) are compounds derived from nature, with photodynamic properties. Natural PSs have a similar action to that of commercial PSs, where cancer cell death occurs by necrosis, apoptosis, and autophagy through ROS generation. Natural PSs have garnered great interest over the last few decades because of their high biocompatibility and good photoactivity. Specific wavelengths could cause phytochemicals to produce harmful ROS for photodynamic therapy (PDT). However, natural PSs have some shortcomings, such as reduced solubility and lower uptake, making them less appropriate for PDT. Nanotechnology offers an opportunity to develop suitable carriers for various natural PSs for PDT applications. Various nanoparticles have been developed to improve the outcome with enhanced solubility, optical adsorption, and tumor targeting. Multidrug resistance (MDR) is a phenomenon in which tumor cells develop resistance to a wide range of structurally and functionally unrelated drugs. Over the last decade, several researchers have extensively studied the effect of natural PS-based photodynamic treatment (PDT) on MDR cells. Though the outcomes of clinical trials for natural PSs were inconclusive, significant advancement is still required before PSs can be used as a PDT agent for treating MDR tumors. This review addresses the increasing literature on MDR tumor progression and the efficacy of PDT, emphasizing the importance of developing new nano-based natural PSs in the fight against MDR that have the required features for an MDR tumor photosensitizing regimen.

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.

Current appraises of therapeutic applications of nanocurcumin: A novel drug delivery approach for biomaterials in dentistry

Curcumin is a natural herb and polyphenol that is obtained from the medicinal plant Curcuma longa. It's anti-bacterial, anti-inflammatory, anti-cancer, anti-mutagenic, antioxidant and antifungal properties can be leveraged to treat a myriad of oral and systemic diseases. However, natural curcumin has weak solubility, limited bioavailability and undergoes rapid degradation, which severely limits its therapeutic potential. To overcome these drawbacks, nanocurcumin (nCur) formulations have been developed for improved biomaterial delivery and enhanced treatment outcomes. This novel biomaterial holds tremendous promise for the treatment of various oral diseases, the majority of which are caused by dental biofilm. These include dental caries, periodontal disease, root canal infection and peri-implant diseases, as well as other non-biofilm mediated oral diseases such as oral cancer and oral lichen planus. A number of in-vitro studies have demonstrated the antibacterial efficacy of nCur in various formulations against common oral pathogens such as S. mutans, P. gingivalis and E. faecalis, which are strongly associated with dental caries, periodontitis and root canal infection, respectively. In addition, some clinical studies were suggestive of the notion that nCur can indeed enhance the clinical outcomes of oral diseases such as periodontitis and oral lichen planus, but the level of evidence was very low due to the small number of studies and the methodological limitations of the available studies. The versatility of nCur to treat a diverse range of oral diseases augurs well for its future in dentistry, as reflected by rapid pace in which studies pertaining to this topic are published in the scientific literature. In order to keep abreast of the latest development of nCur in dentistry, this narrative review was undertaken. The aim of this narrative review is to provide a contemporaneous update of the chemistry, properties, mechanism of action, and scientific evidence behind the usage of nCur in dentistry.