Ethylcellulose Inserts of an Orphan Drug for Periodontitis: Preparation,In Vitro,and Clinical Studies

Ethylcellulose inserts of niridazole fabricated by casting were studied for in vitro release and in vivo clinical effectiveness. The in vitro drug release was steady and sustained for over 7 days and followed diffusion kinetics. Selected batch, EN3, was evaluated clinically in patients with periodontitis for 6 months. A significant improvement (α ≤ 0.05) in clinical indices from baseline was observed. Intergroup study revealed a significant (α ≤ 0.01) change in the bleeding index, gingival index, plaque index, calculus criteria, and pocket depth. Significant reduction in total bacterial count in gingival crevicular fluid was observed before and postdevice insertion, as well as between control and treatment groups.     

Mechanistic analysis of PLGA/HPMC-based in-situ forming implants for periodontitis treatment

In-situ forming implant formulations based on poly(lactic-co-glycolic acid) (PLGA), acetyltributyl citrate (ATBC), minocycline HCl, N-methyl pyrrolidone (NMP) and optionally hydroxypropyl methylcellulose (HPMC) were prepared and thoroughly characterized in vitro. This includes electron paramagnetic resonance (EPR), nuclear magnetic resonance (¹H NMR), mass change and drug release measurements under different conditions, optical microscopy, size exclusion chromatography (SEC) as well as antibacterial activity tests using gingival crevicular fluid samples from periodontal pockets of periodontitis patients. Based on these results, deeper insight into the physico-chemical phenomena involved in implant formation and the control of drug release could be gained. For instance, the effects of adding HPMC to the formulations, resulting in improved implant adherence and reduced swelling, could be explained. Importantly, the in-situ formed implants effectively hindered the growth of bacteria present in the patients’ periodontal pockets. Interestingly, the systems were more effectively hindering the growth of pathogenic bacterial strains (e.g., Fusobacterium nucleatum) than that of strains with a lower pathogenic potential (e.g., Streptococcus salivarius). In vivo, such a preferential action against the pathogenic bacteria can be expected to give a chance to the healthy flora to re-colonize the periodontal pockets.     

Consensus report of the joint workshop of the Italian Society of Diabetology,Italian Society of Periodontology and Implantology,Italian Association of Clinical Diabetologists (SID-SIdP-AMD)

Periodontitis has been defined as the Sixth complication of Diabetes Mellitus. Since both diabetes mellitus and periodontitis have a high prevalence in the general population, the Italian Society of Diabetology, the Italian Society of Periodontology and Implantology and the Italian Association of Clinical Diabetologists revised the present scientific literature in the present consensus report.A bi-directional interaction was demonstrated: Patients affected by type 1 and type 2 diabetes have a higher prevalence of periodontitis than the general population, due to several metabolic factors (e.g. chronic hyperglycemia, autoimmunity, dietary and life-style factors); similarly, periodontitis predisposes to type 2 diabetes mellitus mainly via the increase of systemic cytokines release. Conversely, improvement of metabolic control of diabetic patients delay the progression of periodontitis as well as periodontitis treatment reduces glycosylated hemoglobin levels in blood.Due to the bi-directional causal interaction between periodontitis and diabetes mellitus, a strict collaboration among dentists and diabetologists is required and strongly recommended. The inter-societies consensus proposes specific flow-diagrams to improve the treatment of patients and management of the general population regarding the issue of periodontitis and diabetes.     

Role of gingival mesenchymal stem cell exosomes in macrophage polarization under inflammatory conditions

ObjectiveExosomes have been shown to play a strong role in intercellular communication. While GMSCs have been extensively studied, less research exists on exosomes derived from GMSCs, especially on how exosomes affect macrophages. This study aimed to investigate the impact of GMSC-derived exosomes on macrophage polarization and phenotype under inflammatory conditions.MethodsExosomes were isolated from GMSCs-conditioned media by ultracentrifugation (UC) and characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western blot (WB). In vitro, GMSC-derived exosomes were co-incubated with macrophages for 24 h in the absence or presence of M1 polarizing conditions in the six-well plate. The protein and mRNA expression levels of M1 and M2 macrophage markers were detected and the supernatants were collected for an enzyme-linked immunosorbent assay (ELISA).ResultsExosomes were successfully isolated from GMSCs. Macrophages co-cultured with exosomes showed significantly decreased levels of the M1 markers Tumor Necrosis Factor-α (TNF-α), Interleukin-12 (IL-12), CD86 and Interleukin-1β (IL-1β). By contrast, M2 marker Interleukin-10 (IL-10) levels moderately increased. Meanwhile, similar results were acquired in the cell culture supernatants.ConclusionGMSC-derived exosomes may promote M1 macrophage transformation into M2 macrophages, reducing the pro-inflammatory factors produced by M1 macrophages.     

肥大细胞Toll样受体4在人慢性牙周炎牙龈组织中的表达

 目的：观察人慢性牙周炎牙龈组织中肥大细胞Toll样受体4（Toll-like receptor 4, TLR4）的表达,并探讨其在牙周炎发病中的可能作用。方法: 将68例自愿接受本研究的牙周炎患者按照牙周炎的病变程度分成3组：轻度牙周炎组（23例）、重度牙周炎组（25例）和正常对照组（20例）。取牙龈组织标本,4%中性甲醛液固定48 h以上。制作牙龈组织的连续切片,HE染色,光学显微镜下观察各实验组牙龈组织的组织学改变;免疫组化法染色观察各实验组牙龈组织TLR4的表达;免疫荧光双染色法观察TLR4在肥大细胞中的表达。结果： (1)与正常对照组相比,各慢性牙周炎组牙龈组织中TLR4的表达及TLR4在肥大细胞中的表达均显著升高（P<005）;(2)重度牙周炎组牙龈组织中TLR4表达的数量及TLR4在肥大细胞中的表达明显高于轻度牙周炎组（P<005）。结论：TLR4在牙龈组织中的表达及在肥大细胞中的表达量随着牙周炎的炎症程度加重而增加,提示TLR4,特别是肥大细胞TLR4可能在慢性牙周炎的发病和疾病进程中起着重要的作用。     

The first study to detect co-infection of Entamoeba gingivalis and periodontitis-associated bacteria in dental patients in Taiwan

Periodontitis, an inflammatory disease of the oral cavity, was caused by microbes from bacteria to protozoa. In this study, we detected protozoa, Entamoeba gingivalis and other three common pathogenic bacteria, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia by the Polymerase chain reaction (PCR) on patients.     

The effect of overbite and overjet on clinical parameters of periodontal disease: A case control study

AimTo investigate the association of overjet and overbite with clinical parameters of periodontal disease.Material and methodsThe study was performed in Riyadh, Saudi Arabia, from March 2017 to March 2018. 600 Saudi males aged 20–30 years old were included. Participants were divided into three groups (n: 200) depending on the presence of overjet (OJ) or overbite (OB) and its relationship with periodontal disease. Periodontal parameters were assessed clinically and radiographically. One-way analysis of variance was used to test for any significant differences between groups. Tukey’s post hoc comparison test was used to evaluate correlations among parameters.ResultsOJ exceeding 8 mm was correlated with debris, calculus, and periodontal scores on mandibular anterior teeth, especially on the lingual surfaces.Both OJ and OB groups showed significantly increased PD, compared to that of the control group in measurement at the lingual (P = 0.004, 0.003) and proximal (P = 0.002, 0.002) surfaces of the lower anterior teeth. Finally, the CEJ-AB was statistically significantly higher in the OB group compared to the OJ and control groups (P = 0.091, 0.008).ConclusionThe present study found a correlation between OJ and OB and periodontal disease, as measured using specific parameters. This indicates that periodontal treatment may be insufficient unless the overjet or overbite is corrected.