Innovative root-end filling materials based on calcium-silicates and calcium-phosphates.

This in vitro study evaluated the apical sealing ability, bioactivity and biocompatibility of an experimental calcium silicate-based and two light-curing calcium silicate/calcium-phosphate cements as potential root end filling materials. A calcium silicate Portland-based (Control PC), an experimental calcium silicate (Exp. PC) and two light-curing cements (LC-CaP; LC-Si/CaP) were assessed for their alkalinising activity (pH) and biocompatibility. Single-rooted human canines were endodontically treated, filled with gutta-percha and finally submitted to apicoectomy. Root end fillings were performed using all tested cements, and their apical sealing ability was evaluated up to 4 weeks of immersion in simulated body fluid (SBF). The mineral precipitation at the apical region and the cement adaptation to root dentine were also evaluated through non-destructive optical microscopy both at 24 h and after prolonged water storage (four week). LC-CaP and LC-Si/CaP had neutral pH, the greatest sealing ability (24 h) and excellent cytocompatibility. The Exp. PC cement presented sealing ability after two and four weeks, as well as biocompatibility after four and seven days, similar to LC-CaP and LC-Si/CaP. The control PC cement showed the lowest sealing ability and the greatest cytotoxicity. Mineral precipitation was observed in all groups, while some differences were seen in terms of cement adaptation along the root canal dentine walls. The experimental light-curable cements as well as the experimental PC might be suitable root end filling materials with appropriate (in vitro) sealing ability, biocompatibility and aptitude to induce mineral precipitation.

Enhancing the physical and structural properties of poly(glycolide-co-trimethylene carbonate-co-ε-caprolactone) copolymer fibers.

Nowadays, due to the methodological needs in the application of internal surgery new methods evolving novel design for surgical suture are recommended. In this work, the effect of cold drawing process and the thermal annealing process on the different optical and structural properties of surgical suture fibers were studied. For the thermal annealing process, samples of Monosyn monofilaments suture fibers were thermally annealed at temperatures ranging from 50 to 100 ° C for annealing time = 120 min. The thermal treatment was carried out under free end condition. For the cold drawing process, an Instron was used to mechanically draw and measures the tensile stress strain curve of Monosyn samples. Using differential scanning calorimetry, X-ray diffraction techniques, and optical polarizing microscope the different properties of the tested sutures, such as the crystallinity, sample radius, birefringence, molecular orientation, and tensile properties were measured. From the resulting data, there was a marked increase in the physical and structural properties during the thermal annealing and cold drawing processes. This means that a new reorientation of Monosyn suture molecular chains were performed and approved by calculating the different orientations f(θ) and fc . This is an important improvement for these biodegradable materials to widen their medical use and improve their clinical results. RESEARCH HIGHLIGHTS: The stress-strain curve for Monosyn surgical fiber is J shape and identical to the human tissue stress-stain curve. The different orientation calculated improve that the drawing process affect directly on the fiber chain orientations. The fiber chains orientation due to the cold drawing process causes strain induced crystallinity.

Temporal small arterial inflammation is common in patients with giant cell arteritis.

Giant cell arteritis (GCA) primarily involves medium-to-large arteries. Small-vessel inflammation is a recognized phenomenon occurring in association with GCA. However, its significance is poorly elucidated. Histologic sections and medical records of105 temporal artery specimens were retrospectively reviewed between 2008 and 2017 to examine associated clinical manifestations and laboratory data including antinuclear antibody and p-antineutrophilic cytoplasmic antibody titers. Immunohistochemical staining for CD4 and CD8 was performed in select cases to assess the nature of the inflammatory response. Seventy-eight patients meeting the diagnostic criteria of temporal arteritis were included in the analysis. Twenty-eight specimens demonstrated temporal arteritis with small arterial inflammation (SAI), and 50 specimens showed temporal arteritis without SAI. Eight (28.6%) of 28 patients with SAI presented with jaw claudication, whereas 5 (17.9%) were febrile at presentation. In contrast, in 50 patients without SAI, jaw claudication and fever were seen in 11 and 2 cases, respectively (P = .01 and P = .0047, respectively). No statistically significant difference was noted between other symptoms and laboratory indices between the 2 groups. Elevated p-antineutrophilic cytoplasmic antibody titers in GCA may be associated with concomitant polymyalgia rheumatica or treatment-resistant disease. We also identified a higher count of CD4 and CD8 T cells in SAI cases, although the ratio of CD4/CD8 T lymphocytes was within normal limits. In conclusion, simultaneous involvement of arterioles and medium- to large-sized arteries is common in GCA and may be associated with treatment-refractory disease. Documentation of small arterial involvement in GCA will help the clinicians to manage the disease more effectively.