Investigation of Different Types of Micro- and Nanostructured Materials for Bone Grafting Application

The insufficient volume of dental ridges is one of the most severe problems regarding an oral cavity. An inadequate amount can cause problems during various types of dental treatment. Its complexity originates from the etiopathogenesis of this problem. In this study, the representatives of auto-, allo-, and xenografts are compared. The physic-chemical differences between each of them were evaluated using XRD (X-ray Powder Diffraction), a SEM (Scanning Electron Microscopy), FT-IR (Fourier transformed infrared spectroscopy), and TGA (thermogravimetric analysis). Based on the SEM images, it was observed that the origin of the material has an influence on collagen fiber compact level and porosity. Following a comparison of FT-IR spectra and XRD, the crystal and chemical structures were described. Based on TGA, different water concentrations of the investigated materials, their high thermal stability, and concentration of inorganic phase, hydroxyapatite was determined. The presented study is important because it delivers information about chemical structure and its impact on bone regeneration. This knowledge should be taken into consideration by dental clinicians, because different types of bone grafts can accommodate the achievement of various goals

The Potential Selective Cytotoxicity of Poly (L- Lactic Acid)-Based Scaffolds Functionalized with Nanohydroxyapatite and Europium (III) Ions toward Osteosarcoma Cells

Osteosarcoma (OSA) is malignant bone tumor, occurring in children and adults, characterized by poor prognosis. Despite advances in chemotherapy and surgical techniques, the survival of osteosarcoma patients is not improving significantly. Currently, great efforts are taken to identify novel selective strategies, distinguishing between cancer and normal cells. This includes development of biomimetic scaffolds with anticancer properties that can simultaneously support and modulate proper regeneration of bone tissue. In this study cytotoxicity of scaffolds composed from poly (L-lactic acid) functionalized with nanohydroxyapatite (nHAp) and doped with europium (III) ions—10 wt % 3 mol % Eu3+: nHAp@PLLA was tested using human osteosarcoma cells: U-2 OS, Saos-2 and MG-63. Human adipose tissue-derived stromal cells (HuASCs) were used as non-transformed cells to determine the selective cytotoxicity of the carrier. Analysis included evaluation of cells morphology (confocal/scanning electron microscopy (SEM)), metabolic activity and apoptosis profile in cultures on the scaffolds. Results obtained indicated on high cytotoxicity of scaffolds toward all OSA cell lines, associated with a decrease of cells’ viability, deterioration of metabolic activity and activation of apoptotic factors determined at mRNA and miRNA levels. Simultaneously, the biomaterials did not affect HuASCs’ viability and proliferation rate. Obtained scaffolds showed a bioimaging function, due to functionalization with luminescent europium ions, and thus may find application in theranostics treatment of OSA

<p>Fe₃O₄ Magnetic Nanoparticles Under Static Magnetic Field Improve Osteogenesis via RUNX-2 and Inhibit Osteoclastogenesis by the Induction of Apoptosis</p>

International audiencePurpose: The presented study aimed to investigate the effects of Fe 3O 4 nanoparticles and static magnetic field on osteoblast and osteoclasts’ metabolic activity.Methods: Magnetic nanoparticles were prepared by a wet chemical co-precipitation process and analyzed using X-ray powder diffraction, high-resolution transmission electron microscope (HRTEM), dynamic light scattering (DLS), laser Doppler velocimetry, Raman and the Mössbauer spectroscopy. In vitro experiments were performed using MC3T3, 4B12 and RAW 264.7 cell lines. Cells were cultured in the presence of nanoparticles and with or without exposure to the magnetic field. Proteins were investigated with Western blotting and immunofluorescence and Western blot. Gene expression was analyzed with a quantitative real-time polymerase chain reaction.Results: Obtained particles were in the nano-range (average size around 50 nm) and had a spherical-like morphology. The typical hydrodynamic size was in the range 178– 202 nm and Zeta potential equaled – 9.51 mV. Mössbauer spectrum corresponds to the Fe+3 ions in tetrahedral (A) and Fe+3 and Fe+2 ions in octahedral (B) sites of Fe 3O 4. In vitro study revealed cytocompatibility and anti-inflammatory effects of fabricated nanoparticles. Furthermore, it was shown that nanoparticles combined with magnetic field exposure enhance osteogenic differentiation of MC3T3 cells by upregulation of RUNX-2 activity. Under the same experimental condition, nanoparticles and magnetic field decreased osteoclastogenesis of 4B12 by the induction of apoptosis through the mitochondrial-dependent pathway.Conclusion: Fe 3O 4 nanoparticles together with magnetic field can be applied for the fabrication of novel biomaterials for the treatment of bone disorders related to bone loss in which a balance between bone-forming and resorbing cells is disturb

Comparison of Selected Non-Coding RNAs and Gene Expression Profiles between Common Osteosarcoma Cell Lines

Osteosarcoma (OS) is a bone tumour affecting adolescents and elderly people. Unfortunately, basic treatment methods are still underdeveloped, which has a high impact on the poor survivability of the patients. Studies designed to understand the underlying mechanisms of osteosarcoma development, as well as preclinical investigations aimed at establishing novel therapeutic strategies, rely significantly upon in vitro models, which apply well-established cell lines such as U-2 OS, Saos-2 and MG-63. In this study, the expression of chosen markers associated with tumour progression, metastasis and survival were identified using RT-qPCR. Levels of several onco-miRs (miR-21-5p, miR-124-3p, miR-223-3p and miR-320a-3p) and long non-coding RNA MEG3 were established. The mRNA expression of bone morphogenetic proteins (BMPs), including BMP-2, BMP-3, BMP-4, BMP-6, BMP-7, as well as their receptors: BMPR-IA, BMPR-IB and BMPR-II was also determined. Other tested markers included metalloproteinases, i.e., MMP-7 and MMP-14 and survivin (BIRC5), C-MYC, as well as CYCLIN D (CCND1). The analysis included comparing obtained profiles with transcript levels established for the osteogenic HeLa cell line and human adipose-derived stromal cells (hASCs). The tested OS cell lines were characterised by a cancer-related phenotype, such as increased expression of mRNA for BMP-7, as well as MMP-7 and MMP-14. Osteosarcoma cells differ considerably in miR-21-5p and miR-124-3p levels, which can be related to uncontrolled tumour growth. The comprehensive examination of osteosarcoma transcriptome profiles may facilitate the selection of appropriate cell models for preclinical investigations aimed at the development of new strategies for OS treatment

Thermographic evaluation of experimental pleurisy induced by carrageenan and modified by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

The use of a thermal imaging camera may improve the detection of changes during inflammation process propagation in animals and humans that could be caused by numerous factors like 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Methods: Rats were randomised and divided into two groups, C group, in which experimental pleural inflammatory reaction was evoked and TCDD group, in which a single dose was applied 21 days before administration of 1% carrageenan solution. Infrared thermograms were taken with a microbolometer thermal imaging camera MobIR M8. The surface temperature distribution was measured in three randomly selected animals. Results: In the analysis of correlation we found negative results between both groups. In the C group, the pleurisy was developed and allowed to develop freely. It can be observed that both the average maximum temperature and the average minimum temperature were the highest after 48 hours after injection of the 1% carrageenan in solution. In TCDD group, lowered temperature in all days of experiments was noted. However, the increase of temperature after carrageenan injection was similar. The main changes observed in the lungs were oedema, hyperemia with clot formation and changes in lung structure. Several proliferative changes in the lungs were noted. Moreover, increased number of goblet cells as well and increased release of the surfactant was observed. The activation of fibroblasts and synthesis of collagen fibers was noted. Conclusions: The TCDD administration results in the reduction of superficial temperature, which is easily detectable by thermal imaging camera that can be effectively used in monitoring the course of inflammation

Lanthanum Molybdate Nanoparticles from the Bradley Reaction: Factors Influencing Their Composition, Structure, and Functional Characteristics as Potential Matrixes for Luminescent Phosphors

The article reflects on the body and on the health and illness process as non-natural facts. Starting from a bibliographic review, it uses some ideas of the history of Western Medicine to contextualize body conceptions, sexual differences, and the health and illness process. In addition, it discusses other medical rationalities and religious cosmologies, in which the conceptions of body, health and illness differ from those of the Western Medicine. It employs some anthropological approaches to show the cultural modeling of the body and its uses; the symbolic dimension and its inclusion in the network of social relations and norms and also its links with the environment and the representations of the person, through ethnographic examples extracted from the literature.O artigo reflete, a partir de revisão bibliográfica, sobre o corpo e o processo saúde e doença como fatos não naturais. Vale-se de algumas ideias da história da Medicina Ocidental para contextualizar as concepções do corpo, as diferenças sexuais e a saúde e doença, assim como de outras racionalidades médicas e cosmologias religiosas onde as concepções do corpo e da saúde e doença diferem da medicina ocidental. Recorre a algumas abordagens antropológicas para mostrar a modelagem cultural do corpo e de seus usos; a dimensão simbólica e sua emersão na teia das relações e normas sociais e nas relações com o meio ambiente, assim como suas articulações com a representação da pessoa, através de exemplos etnográficos extraídos da literatura

Clinical and therapeutic aspects of root caries including the Er:YAG laser and ozone therapy

Próchnica korzenia jest chorobą cementu korzeniowego występującą zazwyczaj u osób starszych. Przyczyną jest odsłonięcie cementu korzeniowego i zalegająca płytka nazębna. Odsłonięcie następuje poprzez obniżenie przyczepu nabłonkowego w wyniku recesji lub choroby przyzębia. Czynnikami ryzyka próchnicy korzenia są zła higiena, dieta bogata w węglowodany, zaburzenia wydzielania śliny. Zasadnicze leczenie polega na eliminacji czynników ryzyka, profilaktyce fluorkowej, leczeniu odtwórczym. Obecnie coraz częściej wykorzystuje się ozonoterapię oraz opracowywanie chorobowo zmienionych tkanek przy pomocy lasera erbowo-yagowego.The root caries is a root’ cement disease that usually occurs in older people. The cause is the exposure of the root cement and residual plaque. Exposure occurs by lowering the epithelial attachment as a result of recession or periodontal disease. Risk factors for root caries are poor hygiene, a carbohydrate-rich diet, salivary flow disorders. The basic treatment consists in the elimination of risk factors, fluoride prophylaxis and restorative treatment. Currently, the ozone therapy and the erbium-yag laser are more often used in root caries treatment

SEM Evaluation of Tooth Surface after a Composite Filling Removal Using Er:YAG Laser, Drills with and without Curettes, and Optional EDTA or NaOCl Conditioning

(1) Background: This study aimed to evaluate the microporosity of the tooth surface structure adjacent to the cemento-enamel junction (CEJ) after the removal of composite fillings with a drill in comparison with removal by an Er:YAG laser and after cleaning with a periodontal curette, chemical EDTA and NaOCl (sodium hypochlorite) conditioning. (2) Methods: The research material consisted of 30 extracted premolars with cervical composite fillings. The teeth were divided into six groups according to the method of tooth preparation: group G1 (n = 5)—a diamond drill; group G2 (n = 5)—a diamond drill + curette; group G3 (n = 5)—a diamond drill + 24% EDTA (PrefGel, Straumann, Switzerland); group G4 (n = 5)—an Er:YAG laser (LightWalker, Fotona, Ljubljana, Slovenia) set with the following parameters: power: 1.65 W (composite removal, CR), 1.2 (tooth conditioning, TC), energy: 110 mJ (CR), 80 mJ (TC), frequency: 15 Hz, pulse duration: 50 μs, tip diameter: 1 mm, air/fluid cooling: 4, distance 1.5 mm, energy density: 14.01 J/cm2 (CR), 10.19 J/cm2 (TC); group G5 (n = 5)—an Er:YAG laser + 2% sodium hypochlorite (NaOCl); group G6 (n = 5)—an Er:YAG laser + 5.25% NaOCl. In each tooth, three cavities were made and subjected to analysis. The dentin surface was evaluated using a scanning electron microscope (SEM). (3) Results: Groups G1 and G2 exhibited mechanical damage to the tooth surface structure caused by the rotary motion of a diamond drill. The SEM image showed a smear layer that could only be removed chemically using 24% EDTA gel (group G3). The tooth surfaces prepared with the Er:YAG laser (groups G4–G6) revealed a homogeneous structure without damage along with open dentinal tubules (without smear layer) and visible denaturation of collagen fibers. The sodium hypochlorite (NaOCl) conditioning did not increase the visibility of dentinal tubules. (4) Conclusions: Dentin surfaces have open dentinal tubules after removal of the composite filling using the Er:YAG laser and therefore do not require additional NaOCl conditioning

Nanomaterials Application in Endodontics

In recent years, nanomaterials have become increasingly present in medicine, especially in dentistry. Their characteristics are proving to be very useful in clinical cases. Due to the intense research in the field of biomaterials and nanotechnology, the efficacy and possibilities of dental procedures have immensely expanded over the years. The nano size of materials allows them to exhibit properties not present in their larger-in-scale counterparts. The medical procedures in endodontics are time-consuming and mostly require several visits to be able to achieve the proper result. In this field of dentistry, there are still major issues about the removal of the mostly bacterial infection from the dental root canals. It has been confirmed that nanoparticles are much more efficient than traditional materials and appear to have superior properties when it comes to surface chemistry and bonding. Their unique antibacterial properties are also promising features in every medical procedure, especially in endodontics. High versatility of use of nanomaterials makes them a powerful tool in dental clinics, in a plethora of endodontic procedures, including pulp regeneration, drug delivery, root repair, disinfection, obturation and canal filling. This study focuses on summing up the current knowledge about the utility of nanomaterials in endodontics, their characteristics, advantages, disadvantages, and provides a number of reasons why research in this field should be continued