Clinical, bacterial, and inflammatory outcomes of indocyanine green-mediated photodynamic therapy for treating periimplantitis among diabetic patients: A randomized controlled clinical trial.

Background This 6-months randomized controlled clinical trial aimed to assess the efficacy of indocyanine green mediated photodynamic therapy (ICG-PDT) as an adjunct to peri­implant manual debridement (PIMD) versus PIMD alone among Diabetes Mellitus (DM) patients in the treatment of peri­implantitis. Methods A total of 48 DM patients having 64 implants were treated with either ICG-PDT + PIMD (n = 35 implants) or PIMD alone (n = 29 implants). Clinical (probing depth [PD], bleeding on probing [BOP], and plaque index [PI]) and radiographic (peri­implant crestal bone loss [PCBL]) peri­implant variables were recorded. Bacterial species including Porphyromonas gingivalis and Treponema denticola were evaluated from peri­implant plaque biofilms. Levels of interleukin (IL)-1ß and IL-6 were assessed after the collection of peri­implant sulcular fluid. All the evaluations were carried out at baseline, 3- and 6-months. The significance level was set to p < 0.05. Results All clinical parameters significantly reduced within both treatment groups (P<0.05). Intra-group comparison indicates that there was statistically significant reduction in PD and suppuration for ICG-PDT group (P<0.05). There was a statistically significant difference in the BOP between ICG-PDT and PIMD groups at both follow-up periods (P<0.001). However, there was a significant difference for PD (P = 0.001), suppuration (P = 0.01), and PCBL (P = 0.04) on 6 months follow-up between ICG-PDT and PIMD groups, respectively. Only ICG-PDT showed a significant reduction in P. gingivalis and T. denticola on both 3 months and 6 months follow-up compared to baseline. PIMD showed a statistically significant reduction only on 3 months follow-up compared to baseline. This reduction was maintained for both the species when dental implants were treated with ICG-PDT. However, PIMD failed to maintain this reduction until 6 months. Only at 3 months assessment that both treatment groups showed statistically significant reduction in IL-1ß and IL-6 with no significant difference between the groups. Both biomarkers failed to maintain the reduction in both groups and significantly increased levels for IL-1ß was noted at 6 months follow up Conclusion Multiple application of indocyanine-green mediated photodynamic therapy resulted in improved clinical and microbial parameters among type 2 DM subjects in the treatment of peri­implantitis. This clinical trial was registered in the ClinicalTrials.gov Protocol Registration and Results System with registration record number: NCT04833569.

Effects of resolvin D1 on cell survival and cytokine expression of human gingival fibroblasts.

BACKGROUND: Tissue breakdown in periodontitis is initiated by bacteria, such as Porphyromonas gingivalis, and is caused largely by host responses. Resolvins protect the host against acute inflammation by blocking the migration of polymorphonuclear neutrophils to initiate resolution. The effects of resolvins on human gingival fibroblasts (HGFs) are unknown. This study examines the effects of resolvin D1 on HGF survival and cytokine expression when treated with or without P. gingivalis supernatant. METHODS: Cytotoxicity of resolvin D1 on HGFs with or without a toxic level of P. gingivalis supernatant was measured with lactate dehydrogenase assays. Cytokine arrays were performed on HGF-conditioned media treated with or without resolvin D1 and with or without P. gingivalis supernatant. RESULTS: Resolvin D1 had no cytotoxic effects on HGFs at concentrations between 1 and 1,000 nM (all P > 0.05). Resolvin D1 (1,000 nM) significantly inhibited the toxic effects of 13.5% (v/v) P. gingivalis supernatant on HGFs (P = 0.002). Resolvin D1 significantly reduced the expression of interleukin (IL)-6 (P = 0.010) and monocyte chemoattractant protein (MCP)-1 (P = 0.04) in untreated fibroblasts. P. gingivalis (10%) supernatant significantly increased the expression levels of granulocyte-macrophage colony-stimulating factor (CSF), granulocyte CSF, growth-regulated oncogene (GRO), IL-5, IL-6, IL-7, IL-8, IL-10, MCP-1, MCP-2, MCP-3, and monokine induced by γ-interferon. Resolvin D1 significantly reduced the expression of GRO (P = 0.04), marginally reduced the levels of MCP-1 (P = 0.10), and marginally increased the levels of transforming growth factor (TGF)-ß1 (P = 0.07) from HGFs treated with P. gingivalis supernatant. CONCLUSIONS: Resolvin D1 altered the cytotoxicity of P. gingivalis supernatant on HGFs. Resolvin D1 significantly reduced GRO, marginally reduced MCP-1, and marginally increased TGF-ß1 from P. gingivalis-treated HGFs, which could alter the ability of P. gingivalis to induce inflammation.