ABSTRACT
OBJECTIVE: In this study a dentistry nanocomposite with prolonged antibacterial activity using silica nanoparticles (SNPs) loaded with chlorhexidine (CHX) was developed. METHODS: SNPs were coated with the Layer-by-Layer technique. Dental composites were prepared with organic matrix of BisGMA/TEGDMA and SNPs with or without CHX (0, 10, 20 or 30% w/w). The physicochemical properties of the developed material were evaluated and agar diffusion method was used to test the antibacterial. In addition, the biofilm inhibitory activity of the composites was evaluated against S. mutans. RESULTS: SNPs were rounded with diameters about 50 nm, the organic load increased with increasing deposited layers. Material samples with SNPs loaded with CHX (CHX-SNPs) showed the highest values of post-gel volumetric shrinkage, that ranged from 0.3% to 0.81%. Samples containing CHX-SNPs 30% w/w showed the highest values of flexural strength and modulus of elasticity. Only samples containing SNPs-CHX showed growth inhibition against S. mutans, S. mitis and S. gordonii in a concentration-dependent manner. The composites with CHX-SNPs reduced the biofilm formation of S. mutans biofilm at 24 h and 72 h. SIGNIFICANCE: The nanoparticle studied acted as fillers and did not interfere with the evaluated physicochemical properties while providing antimicrobial activity against streptococci. Therefore, this initial study is a step forward to the synthesis of experimental composites with improved performance using CHX-SNPs.
Subject(s)
Chlorhexidine , Nanoparticles , Chlorhexidine/pharmacology , Chlorhexidine/chemistry , Silicon Dioxide/pharmacology , Silicon Dioxide/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Nanoparticles/chemistry , Streptococcus mutansABSTRACT
BACKGROUND: Statins are widely used for the treatment of hyperlipidemia. However, these drugs have pleiotropic effects that can be promising for the prevention and treatment of oral diseases, such as periodontitis. HIGHLIGHT: This review aimed to identify preclinical, observational, and clinical studies that evaluate the effects and biological mechanisms of statins on oral cells and tissues and those using these drugs to treat periodontitis. A literature survey has been conducted in PubMed using combinations of the uniterms: "statins," "dentistry," "periodontal disease," and "periodontal treatment." In vitro findings showed positive statin results in cell lines related to alveolar bone metabolism by altering the signaling pathway Osteoprotegerin/Receptor Activator of Nuclear Factor Kappa B/Receptor Activator of Nuclear Factor Kappa B Ligand (OPG/RANK/RANKL), stimulating the production of alkaline phosphatase and osteocalcin, and reducing the production of matrix metalloproteinases (MMPs). Animal studies have shown a reduction in alveolar bone loss and osteoclastic activity, in addition to a reduction in inflammatory markers, such as IL-1, IL-6, and TNF-α, when statins were used prophylactically. Clinical trials showed a positive impact on clinical parameters, leading to a higher reduction in probing depth and gain in clinical attachment when a local statin was adjunctively associated with mechanical therapy. CONCLUSION: Statins were shown to be promising for regenerating and stimulating bone activity, with great potential for treating chronic periodontitis. However, further studies are required to confirm its effectiveness.
Subject(s)
Alveolar Bone Loss , Chronic Periodontitis , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Animals , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Receptor Activator of Nuclear Factor-kappa B , Tumor Necrosis Factor-alphaABSTRACT
BACKGROUND: Venous thromboembolism (VTE) is a cause for growing concern in hospitals, has great impact on morbidity and mortality in clinical and surgical patients, and is the leading cause of preventable hospital deaths. Although there are risk assessment models for hospital inpatients, prophylaxis is still underused or is administered incorrectly. OBJECTIVES: To assess the risk profile for VTE in recently hospitalized clinical and surgical patients and evaluate the thromboprophylactic measures implemented in the first 24 hours of hospitalization. METHODS: Cross-sectional study conducted in a large general hospital in the state of São Paulo, Brazil, between March and July 2015. Padua and Caprini scores were used for risk stratification of clinical and surgical patients, respectively, while thromboprophylactic measures were analyzed for compliance with the recommendations contained in the 8th and 9th Consensus of the American College of Chest Physicians. RESULTS: A total of 592 patients (62% clinical and 38% surgical) were assessed. Risk stratification revealed a need for chemoprophylaxis in 42% of clinical patients and 81% of surgical patients (51% high risk and 30% moderate risk). However, 54% of high-risk clinical patients, 85% of high-risk surgical patients, and 4% of moderate-risk surgical patients, who were free from contraindications, were actually given the correct prophylaxis in the first 24 hours of hospitalization. CONCLUSIONS: There is a need to improve patient safety in relation to VTE in the first hours of hospitalization, since there is underutilization of chemoprophylaxis, especially in high-risk clinical patients and moderate-risk surgical patients.
