Biomimetic Apatite/Natural Polymer Composite Granules as Multifunctional Dental Tissue Regenerative Material.

This study presents a comprehensive evaluation of novel composite biomaterials designed for dental applications, aiming to potentially address the prevalent challenge of dental and periodontal tissue loss. The composites consisted of biomimetic hydroxyapatite (mHA) enriched with Mg2+, CO32-, and Zn2+ ions, type I collagen, alginate, and, additionally, chitosan and sericin. The granules were loaded with ibuprofen sodium salt. The investigation encompassed a morphology characterization, a porosity analysis, a chemical structure assessment, and an examination of the swelling behavior, drug release kinetics (ibuprofen), and release profiles of zinc and magnesium ions. The granules exhibited irregular surfaces with an enhanced homogeneity in the chitosan-coated granules and well-developed mesoporous structures. The FT-IR spectra confirmed the presence of ibuprofen sodium, despite overlapping bands for the polymers. The granules demonstrated a high water-absorption capacity, with delayed swelling observed in the chitosan-coated granules. Ibuprofen displayed burst-release profiles, especially in the G1 and G3 samples. In the case of the chitosan-coated granules (G2 and G4), lower amounts of ibuprofen were released. In turn, there was a significant difference in the released amount of magnesium and zinc ions from the granules, which was most likely caused by their different location in the hydroxyapatite crystals. The cytotoxicity assays confirmed the non-cytotoxic behavior of the biomaterial. These findings suggest the potential applicability of these biomaterials in dental scenarios, emphasizing their multifunctional and biocompatible nature.

A New, Biomimetic Collagen-Apatite Wound-Healing Composite with a Potential Regenerative and Anti-Hemorrhagic Effect in Dental Surgery.

The aim of this work was to obtain and characterize composite biomaterials containing two components, namely carbonated hydroxyapatite, which was substituted with Mg2+ and Zn2+ ions, and natural polymer-collagen protein. The following two different types of collagen were used: lyophilized powder of telocollagen from bovine Achilles tendon and atelocollagen solution from bovine dermis. The obtained 3D materials were used as potential matrices for the targeted delivery of tranexamic acid for potential use in wound healing after tooth extractions. Tranexamic acid (TXA) was introduced into composites by two different methods. The physicochemical analyses of the obtained composites included Fourier-transform infrared spectroscopy (FT-IR), inductively coupled plasma-optical emission spectroscopy (ICP-OES), transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), release kinetics tests, swelling test, and cytotoxicity assays. The studies showed that the proposed synthetic methods yielded biomaterials with favorable physicochemical properties, as well as the expected release profile of the drug and ions from the matrices.

The Influence of Strontium on Bone Tissue Metabolism and Its Application in Osteoporosis Treatment.

Osteoporosis is a chronic disease characterized by low bone mass caused by increased bone turnover and impaired bone microarchitecture. In treatment, we use antiresorptive or anabolic drugs, which usually have a unidirectional effect, i.e., they inhibit the activity of osteoclasts or stimulate the effect of osteoblasts. Strontium ranelate is an anti-osteoporosis drug with a unique mechanism of action (used primarily in postmenopausal women). Unlike other medicines, it has a multidirectional effect on bone tissue, intensifying osteoblastogenesis while inhibiting osteoclastogenesis. It turns out that this effect is demonstrated by strontium ions, an element showing physical and chemical similarity to calcium, the basic element that builds the mineral fraction of bone. As a result, strontium acts through the calcium-sensing receptor (CaSR) receptor in bone tissue cells. In recent years, there has been a significant increase in interest in the introduction of strontium ions in place of calcium ions in ceramics used as bone replacement materials for the treatment of bone fractures and defects caused by osteoporosis. The aim of this study was to summarize current knowledge about the role of strontium in the treatment of osteoporosis, its effects (in various forms), and the ways in which it is administered.

Biologically Inspired Collagen/Apatite Composite Biomaterials for Potential Use in Bone Tissue Regeneration-A Review.

Type I collagen and nanocrystalline-substituted hydroxyapatite are the major components of a natural composite-bone tissue. Both of these materials also play a significant role in orthopedic surgery and implantology; however, their separate uses are limited; apatite is quite fragile, while collagen's mechanical strength is very poor. Therefore, in biomaterial engineering, a combination of collagen and hydroxyapatite is used, which provides good mechanical properties with high biocompatibility and osteoinduction. In addition, the porous structure of the composites enables their use not only as bone defect fillers, but also as a drug release system providing controlled release of drugs directly to the bone. This feature makes biomimetic collagen-apatite composites a subject of research in many scientific centers. The review focuses on summarizing studies on biological activity, tested in vitro and in vivo.

[Metabolic control in young children with type 1 diabetes treated with continuous subcutaneous insulin infusion (insulin pump)]. / Wyrównanie metaboliczne u malych dzieci z cukrzyca typu 1 leczonych metoda ciaglego podskórnego wlewu insuliny (pompa insulinowa).

UNLABELLED: Intensive insulin therapy is a method of choice in the management of patients with type 1 diabetes. Its administration in the youngest children is limited by little or no acceptance of multiple injections and a typical fear of needles and syringes. In recent years more and more frequently the method of multiple daily injections (MDI) of insulin is being replaced by the method of continuous subcutaneous insulin infusion (CSII) even in the youngest children. OBJECTIVE: Evaluation of the safety and efficacy of CSII method in children at prepubertal age. MATERIAL AND METHODS: There were 61 children under 10 years of age with type 1 diabetes recruited for the study (33 boys, 28 girls). CSII method was implemented for the period of minimum 6 months. In the group of 21 children CSII method was the first method of their therapy (it was administered at the time of diagnosis). Mean duration of diabetes was 3.0 years +/-1.87 year, mean age at diagnosis was 3.82+/-2.19 years and mean duration of CSII treatment was 1.4 +/-0.75 year. The average HbA1c at the baseline for all children was 8.7+/-1.4%. RESULTS: In the group where CSII therapy was implemented as the first method of management, mean duration of treatment was 1.5 years, mean HbA1c decreased after first 3 months from 9.6+/-1.68% to 7.22+/-0.99% (p<0.05). After 12 and 24 months the value further decreased to 7.01+/-0.57%. In the group that was earlier treated with MDI method (n=40), mean value of HbA1c decreased after 3 months from 8.27+/-1.4% to 7.6 +/-0.86% (p<0.05), after 12 months it further decreased to 7.37+/-0.86%, after 24 months its mean value was 7.53%. The number of patients with HbA1c >8% decreased from 58.4% to 10%. Adverse events were observed only in the group that was earlier treated with the MDI method. There were 3 incidences of severe hypoglycaemia, 2 incidences of diabetic ketoacidosis, 2 incidences of infection at the needle site (in one case the surgical attention was necessary). After two years of the trial there was a statistically significant difference in the mean value of HbA1c between children that used CSII method from the moment of their diagnosis (HbA1c=7.01%) and those who were earlier treated with MDI method (HbA1c=7.53 +/-0.73%). In both groups the daily insulin requirement was similar (CSII method 0.69+/-0.2 unit/kg/day, MDI method 0.75+/-0.19 unit/kg/day). CONCLUSIONS: The method of continuous subcutaneous insulin infusion (CSII) provides good and sustained metabolic control in the youngest children with type 1 diabetes. Administering of that method from the very beginning of the diabetes treatment may decrease the risk of acute complications.