12 research outputs found
Periodontal Considerations in Adult Orthodontic Patients
The relationship between periodontology and orthodontics consists of a highly complex, bidirectional and close interaction that is nowadays characterized by controversial scientific opinions and clinical approaches. The relevant increasing number of adult orthodontic patients which in most cases present already-compromised periodontal tissues has markedly highlighted the potential of orthodontic treatment in enhancing or deteriorating periodontal health and also the outmost relevance of peculiar periodontal planning prior and during orthodontic treatment. Since the progress in adult orthodontics trend is rapid, there is also an increasing need for evidence-based protocols that might guide clinicians through a comprehensive, interdisciplinary and successful treatment. This chapter has been compiled with the aim of providing orthodontists, periodontists and general practitioners with sound evidence-based protocols and valid clinical approaches that have proven to be successful for numerous patients over long follow-ups. It is structured following the steps for a correct therapy management, starting from comprehensive examination and diagnosis to before and during orthodontic treatment considerations, and finally analysing the present state of new adult orthodontic technologies
Synthesis and Study of Fully Biodegradable Composites Based on Poly(butylene succinate) and Biochar
Synthesis and Study of Fully Biodegradable Composites Based on Poly(butylene succinate) and Biochar
Biodegradable polymers offer a promising alternative to the global plastic problems and especially in the last decade, to the microplastics problems. For the first time, samples of poly(butylene succinate) (PBSu) biocomposites containing 1, 2.5, and 5 wt% biochar (BC) were prepared by in situ polymerization via the two-stage melt polycondensation procedure. BC was used as a filler for the PBSu to improve its mechanical properties, thermal transitions, and biodegradability. The structure of the synthesized polymers was examined by 1H and 13C nuclear magnetic resonance (NMR) and X-Ray diffraction (XRD) along with an estimation of the molecular weights, while differential scanning calorimetry (DSC) and light flash analysis (LFA) were also employed to record the thermal transitions and evaluate the thermal conductivity, respectively. It was found that the amount of BC does not affect the molecular weight of PBSu biocomposites. The fine dispersion of BC, as well as the increase in BC content in the polymeric matrix, significantly improves the tensile and impact strengths. The DSC analysis results showed that BC facilitates the crystallization of PBSu biocomposites. Due to the latter, a mild and systematic increase in thermal diffusivity and conductivity was recorded indicating that BC is a conductive material. The molecular mobility of PBSu, local and segmental, does not change significantly in the biocomposites, whereas the BC seems to cause an increase in the overall dielectric permittivity. Finally, it was found that the enzymatic hydrolysis degradation rate of biocomposites increased with the increasing BC content
Experimental and Numerical Study of Blood Flow in µ-vessels:Influence of the Fahraeus–Lindqvist effect
Mechanical and thermal properties of PMMA resin composites for interim fixed prostheses reinforced with calcium β-pyrophosphate
Composite PLGA–nanobioceramic coating on moxifloxacin-loaded akermanite 3D porous scaffolds for bone tissue regeneration
Analysis of the osteogenic and mechanical characteristics of iron (Fe2+/Fe3+)-doped β‑calcium pyrophosphate
The calcium phosphate is the main mineral constituent of bone. Although there has been significant amount of research on finding ideal synthetic bone, no suitable scaffold material has yet been found. In this investigation, the iron doped brushite (CaHPO4·2H2O) has been investigated for osteogenic potential and mechanical properties. The synthesis of iron-oxide doping in the form of Fe2+,3+-ions were carried out using the solution based method in which the ammonium hydrogen phosphate and calcium nitrate solutions were used in stoichiometric ratio for synthesizing CaHPO4·2H2O, with doping concentrations of Fe2+,3+-ions between 5 mol% and 30 mol%. The synthesized powders were analysed using X-ray powder diffraction, FTIR, SEM and Raman spectroscopic techniques. The heat treatment of synthesized powder was carried out at 1000 °C in air for 5 h, and it was found that the dominant crystalline phase in samples with <20 mol% was β-CPP, which also formed an iron-rich solid solution phase. Increasing the concentrations of Fe2+,3+-ions enhances the phase fraction of FePO4 and amorphous phase. Amongst the Fe2+,3+-doped β-CPP minerals, it was found that the 10 mol% Fe2+,3+-doped β-CPP offers the best combination of bio-mechanical and osteogenic properties as a scaffold for bone tissue regenerative engineering
Synthesis and Characterization of Mesoporous Mg- and Sr-Doped Nanoparticles for Moxifloxacin Drug Delivery in Promising Tissue Engineering Applications
International audienceMesoporous silica-based nanoparticles (MSNs) are considered promising drug carriers because of their ordered pore structure, which permits high drug loading and release capacity. The dissolution of Si and Ca from MSNs can trigger osteogenic differentiation of stem cells towards extracellular matrix calcification, while Mg and Sr constitute key elements of bone biology and metabolism. The aim of this study was the synthesis and characterization of sol–gel-derived MSNs co-doped with Ca, Mg and Sr. Their physico-chemical properties were investigated by X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDX), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray fluorescence spectroscopy (XRF), Brunauer Emmett Teller and Brunauer Joyner Halenda (BET/BJH), dynamic light scattering (DLS) and ζ-potential measurements. Moxifloxacin loading and release profiles were assessed with high performance liquid chromatography (HPLC) cell viability on human periodontal ligament fibroblasts and their hemolytic activity in contact with human red blood cells (RBCs) at various concentrations were also investigated. Doped MSNs generally retained their textural characteristics, while different compositions affected particle size, hemolytic activity and moxifloxacin loading/release profiles. All co-doped MSNs revealed the formation of hydroxycarbonate apatite on their surface after immersion in simulated body fluid (SBF) and promoted mitochondrial activity and cell proliferation