Effect of hydrosoluble chlorine-mediated antimicrobial photodynamic therapy on clinical parameters and cytokine profile in ligature-induced periodontitis in dogs

Efficacy of Antimicrobial Photodynamic Therapy for Treating Moderate to Deep Periodontal Pockets in Individuals with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Background/Objectives: Diabetes mellitus and periodontitis share a significant, bidirectional relationship. Diabetes raises the risk of periodontitis and influences its severity, impacting tissue repair and bone metabolism. Conversely, periodontal inflammation can disrupt glycemic control, further complicating this interlinked relationship. This systematic review aimed to evaluate the efficacy of antimicrobial photodynamic therapy (aPDT) as an adjunct to subgingival instrumentation (SI) in the treatment of periodontal pockets with a probing pocket depth (PPD) ≥ 5 mm in individuals with type 2 diabetes mellitus (DM2) and periodontitis. Methods: Using the PICOS framework, this review addressed the following question: "How does aPDT as an adjunct to SI compare to SI alone in treating periodontal pockets with PPD ≥ 5 mm in individuals with DM2 and periodontitis?" Databases searched included PubMed, Scopus, and Web of Science up to December 2024. Randomized clinical trials evaluating periodontal status and HbA1c levels in patients with DM2 undergoing periodontal therapy and experiencing SI were included. Patients who received adjunctive aPDT were compared to a control group that received SI alone. A meta-analysis was conducted illustrating treatment effects across groups. Results: After screening 117 studies based on titles and abstracts, three and four studies met the eligibility criteria for quantitative and qualitative analyses, respectively. The principal periodontal parameters assessed included PPD, clinical attachment level (CAL), plaque index (PI), and bleeding on probing (BOP). Forest plots for PD, BOP, PI, and CAL at baseline, three months, and six months revealed no statistically significant differences between the SI+aPDT group and the SI-only group. Glycated hemoglobin across treatment groups was not different. Conclusions: The combination of aPDT with SI provides limited clinical benefits in treating periodontal pockets with a PPD ≥ 5 mm in diabetic patients with periodontitis.

Effect of antimicrobial photodynamic therapy with different photosensitizers and adhesion protocol on the bond strength of resin composite to sound dentin

OBJECTIVES

The aim of this study is to evaluate the influence of the antimicrobial photodynamic therapy with phycocyanin and toluidine blue on the bond strength of resin composite to the sound dentin.

MATERIALS AND METHODS

The samples include 120 tooth blocks taken from 60 human extracted sound third molar teeth. They were randomly divided into 12 groups and disinfected with two different photosensitizers (Phycocyanin and Toluidine blue) activated by 635 nm diode laser for aPDT procedure. Then two different protocols (total-etch and self-etch) of universal adhesive system (G-Premio BOND, GC Dental Products CORP. Japan) were applied. The samples then filled with resin composite (Gradia® Direct, GC Dental Products CORP. Japan). After 10000 cycles of thermocycling, all samples were subjected to the micro shear bond strength (μSBS) test using a universal testing machine (1 mm/min). The data were analyzed with One Way ANOVA.

RESULTS

The effect of aPDT using both photosensitizers (phycocyanin and toluidine blue O) on the bonding strength to dentin was not significant (P>0.05). However, the bonding strength of total etch groups was reduced significantly (P<0.05) after aPDT using both photosensitizers. Phycocyanin self-etch group showed the greatest bonding strength (19.48 ± 3.89 MPa) in comparison to other aPDT groups. No significant reduction after thermocycling in dentin bond strength was observed in all groups (P>0.05), with exception of control total etch groups, which showed significant difference (P<0.05).

CONCLUSION

aPDT using toluidine blue O and phycocyanin has no adverse effect on bonding to sound dentin when using universal adhesive in self-etch protocol.

CLINICAL RELEVANCE

Phycocyanin is more recommended to be used in aPDT in comparison to toluidine blue as a natural photosensitizer.

Antimicrobial photodynamic therapy for inactivation of biofilms formed by oral key pathogens

With increasing numbers of antibiotic-resistant pathogens all over the world there is a pressing need for strategies that are capable of inactivating biofilm-state pathogens with less potential of developing resistances in pathogens. Antimicrobial strategies of that kind are especially needed in dentistry in order to avoid the usage of antibiotics for treatment of periodontal, endodontic or mucosal topical infections caused by bacterial or yeast biofilms. One possible option could be the antimicrobial photodynamic therapy (aPDT), whereby the lethal effect of aPDT is based on the principle that visible light activates a photosensitizer (PS), leading to the formation of reactive oxygen species, e.g., singlet oxygen, which induce phototoxicity immediately during illumination. Many compounds have been described as potential PS for aPDT against bacterial and yeast biofilms so far, but conflicting results have been reported. Therefore, the aim of the present review is to outline the actual state of the art regarding the potential of aPDT for inactivation of biofilms formed in vitro with a main focus on those formed by oral key pathogens and structured regarding the distinct types of PS.