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Objective of the research was to find out the effectiveness of the use of osteoplastic materials based on the multipotent mesenchymal stromal cells of the adipose tissue during surgical treatment for restoration of bone defects in dental patients. The clinical material included examination of 79 patients who underwent replacement of bone defects of the alveolar processes and/or an alveolar part of the appropriate jaw by means of different osteoplastic materials and their combinations or without their application (the control group). Acid phosphatase activity in the oral fluid of patients was determined by means of the unified “end point” method. Alkaline phosphatase activity in the oral fluid was determined using a set of reagents produced by the company “Filisit-Diagnostika” (Ukraine). Oral fluid mineralization index (MI) of patients was calculated according to the ratio of enzymatic activity of alkaline phosphatase (ALP) to acid phosphatase (AP) according to the formula: MI=ALP/AP. Histological material was taken at the stage of installation of a dental implant. It was established that the use of a composition based on multipotent mesenchymal stromal cells of adipose tissue, platelet-enriched blood plasma and bone tissue substitute containing hydroxyapatite contributes to the improvement of regenerative processes in the bone tissue of the jaws, which is confirmed by a 28.68% decrease in acid phosphatase activity, an increase by 25, 97% of alkaline phosphatase activity in the oral fluid of group B patients and, accordingly, a 77.08% increase in the ratio of alkaline to acid phosphatase. According to the results of histological studies and phase-contrast microscopy, after 6-8 months of observation, in patients of group B, the areas of jaw defects were filled with newly formed bone tissue, identical to native bone, and the resulting trepanobioptas had the structure of cancellous bone with osteoblastic elements forming a chain around osteoid tissue. Having analyz

Radiesse is a substance composed of calcium hydroxyapatite commonly administered as a facial filler. Numerous complications such as allergic reactions, edema, necrosis, arterial occlusion or facial paralysis have been described with its increasing use. The formation of nodules away from the injection site has rarely been described in the literature. This article describes the formation of a non-inflammatory nodule at the level of the oral mucosa years after injection of Radiesse in the nasolabial sulcus and discusses the possible causes and treatment options.

Due to a signifi cant increase in the frequency and complexity of maxillofacial injuries, one of the priorities in the development of modern surgical dentistry is the search for new eff ective methods of treating facial bone fractures. In recent decades, the attention of clinicians has been focused on biological treatment methods aimed at restoring bone defects using cell technologies and biological transplants.The aim of the study was to determine the eff ect of using osteoplastic materials based on multipotent adipose- derived mesenchymal stromal cells in dental patients in the surgical treatment of mandibular fractures.Materials and methods. The clinical material included 56 patients, 13 of whom underwent mandibular osteosynthesis with hydroxyapatite bone graft substitute (subgroup 1I), 25 of whom underwent surgery with a combination of multipotent adipose tissue mesenchymal stromal cells, hydroxyapatite bone graft substitute and platelet-rich plasma (subgroup 1B), and 18 of whom underwent spontaneous healing of the fracture line (subgroup 1C). Patients were clinically evaluated on a daily basis. Clinical parameters were assessed on days 1, 3, 5, 7, 10, 14 and 28 after surgery. The postoperative pain syndrome was assessed using the Numerical Rating Scale (NRS), considering the subjective signs of pain in the operated patients.The statistical processing of the study results was performed using the statistical analysis software for biomedical research ‘Microsoft Excel 21’ and ‘Statistica’ (licence number STA862D175437Q). In the statistical processing of the results, we used the variational analysis of series – calculation of the arithmetic mean and its standard error (Mim) – and assessed the signifi cance of diff erences in the results obtained in the comparison groups using the Student’s t-test method. p<0.05 was considered a signifi cant diff erence. [17]. The study was conducted in accordance with the basic provisions of the «Rules of Ethical Principles for S

Following orthopedic surgery, bacterial infection may lead to significant complications related to inflammation in the peri-implant region, including the potential for implant loosening. To address this concern, the surface of metallic implants was modified through the application of bioactive and antibacterial coatings, aiming to mitigate these issues.

In the transition from the laboratory to the clinic, the sterilization of medical devices becomes a fundamental and mandatory step to ensure patient safety. This work evaluates the impact of three different sterilization methods - autoclave, ethylene oxide and gamma irradiation - on the physicochemical properties and degradation kinetics of 3D-printed polycaprolactone\calcium deficient hydroxyapatite (PCL\CDHA) scaffolds for bone regeneration. The in vitro degradation test was performed in phosphate buffer saline solution at 47 °C for 18 weeks by recording the evolution of pH, scaffold morphology, swelling degree, mass loss as well as polymer content, molecular weight and crystallinity. The results showed that under thermally accelerated degradation, the scaffolds underwent hydrolytic bulk degradation without altering the pH of the soaking medium nor compromising the morphology and integrity of the constructs. Although the structural integrity of the scaffolds was maintained, autoclaving severely deteriorated the properties of the polymer, resulting in a faster degradation pattern, confirming that it is not an appropriate sterilization method for PCL\CDHA scaffolds. While ethylene oxide had no significant effect on degradation, gamma irradiation slightly accelerated hydrolysis by chain scission. However, due to the porous nature of the scaffolds, the use of ethylene oxide is inadvisable due to the risk of gas trapping in the pores. Therefore, gamma irradiation, a non-toxic, effective, predictable and reproducible sterilization method, is considered the most appropriate., Peer Reviewed, Postprint (published version)

Synthetic calcium phosphate, particularly hydroxyapatite (HA), has been used in various medical applications due to its biocompatibility and bioactivity. With time, increased interest in the development of HA from natural resources has started to emerge to produce more sustainable biomaterial precursors. HA has been successfully prepared from biogenic waste as the calcium precursor via extraction of calcium oxide from eggshells, seashells, and animal bones (cow, chicken, fish) via the wet method. The dry process, particularly solid-state reaction, has been least preferred due to the tendency of powder contamination and non-homogeneous powder mixing. However, with the proper processing regime, this method can produce pure HA on a mass scale with improved properties as it does not require precise control conditions. In this work, HA was synthesised from eggshell wastes through mechanochemical activation and heat treatment processes. The calcium precursor in pure calcium carbonate (CaCO3) was extracted from eggshells through calcination. Then, the Calcium Hydrogen Phosphate Dihydrate (DCPD) as phosphorus precursor was added to the calcined eggshells via a simple mechanochemical route for 2 hours, and the obtained powder mixture was subjected to heat treatment at 800°C to obtain pure HA. XRD analysis confirmed the formation of phase pure HA in the synthesised powder with an average crystallite size of 26.35 ± 0.1 nm and an average agglomerated particle size of 520 nm. Energy Dispersive X-ray (EDX) analysis has validated the elemental composition of synthesised HA with a Ca/P ratio of 1.76, which closely resembles pure HA with a Ca/P ratio of 1.67. Hence, through calcination, eggshell waste in pure CaCO3 form has been successfully utilised as a sustainable calcium precursor in producing HA via a dry method approach with high potential as a biomaterial for biomedical applications and has indirectly contributed to cost reduction of materials processing.

High viscosity glass ionomer cements (GICs) are widely used in various clinical applications, being particularly effective in atraumatic restorative treatment (ART) due to the synergistic interaction between the material and the technique. However, the inadequate mechanical properties of GICs raise concerns regarding the predictability and longevity of these restorations in areas exposed to occlusal stress. Various modifications of the powder components have been proposed to improve the mechanical strength of GICs to withstand occlusal loading during mastication. In this in vitro study, we investigated whether the nanoparticles (NPs) added to commercially available GICs could fulfill this requirement, which would likely broaden the spectrum of their potential clinical applications. Two commercially available GIC powders (Fuji IX and Ketac Molar), modified by the addition of 5 wt.% TiO2, MgHAp100 or MgHAp1000 NPs, were incorporated into the corresponding liquid in an appropriate ratio, and the mixed cements were evaluated in terms of fracture toughness, flexural strength, Vickers microhardness and rheological tests and compared with the original material. Fuji IX containing 5 wt.% MgHAp100 NPs had lower flexural strength, while Ketac Molar with 5 wt.% TiO2 NPs showed increased fracture toughness. Vickers microhardness increased in Fuji IX following the addition of 5 wt.% TiO2 and MgHAp100 but decreased in Ketac Molar comprising 5 wt.% MgHAp100 (p < 0.05). Achieving a predictable bond between NPs and cement matrix, as well as ensuring a uniform distribution of the NPs within the cement, are critical prerequisites for enhancing the mechanical performance of the original cement.

The corrosion of embedded rebar in self-healing concrete is seldom reported on and deserves more intensive attention. This study focuses on utilizing biomimetic-induced hydroxyapatite as a means of achieving autonomous self-healing to target issues associated with rebar corrosion in concrete structures. A comprehensive evaluation of the synthesized supramolecular hydrogel as self-healing agent carrier, the simulated self-healing products, and the reinforcement corrosion behaviour in the upscaled self-healing concrete beams was conducted. Results show that the synthesized 2,6-bis [N-(carboxyethyl carbonyl)amino] pyridine (DAP) hydrogel qualifies as a healing agent carrier with high loading capacity and intelligent response after cracking. The feasibility of hydroxyapatite formation via a combination of phosphate ions released by the supramolecular hydrogel and the available calcium ions leached by the cement matrix has been substantiated. The addition of phosphate as the healing agent is effective in mitigating the corrosion of rebar in the designed self-healing concrete beam. It can be explained by the synergistic effect of surface adsorption of chloride ions by the formed hydroxyapatite and the corrosion inhibitor role of the released phosphate.

Bacterial cellulose (BC) is a highly pure polysaccharide biopolymer that can be produced by various bacterial genera. Even though BC lacks functional properties, its porosity, three-dimensional network, and high specific surface area make it a suitable carrier for functional composite materials. In the present study, BC-producing bacteria were isolated from kombucha beverage and identified using a molecular method. Two sets of the BC hydrogels were produced in static conditions after four and seven days. Afterwards, two different synthesis pathways were applied for BC functionalization. The first method implied the incorporation of previously synthesized HAp/TiO2 nanocomposite using an immersion technique, while the second method included the functionalization of BC during the synthesis of HAp/TiO2 nanocomposite in the reaction mixture. The primary goal was to find the best method to obtain the functionalized material. Physicochemical and microstructural properties were analyzed by SEM, EDS, FTIR, and XRD methods. Further properties were examined by tensile test and thermogravimetric analysis, and antimicrobial activity was assessed by a total plate count assay. The results showed that HAp/TiO2 was successfully incorporated into the produced BC hydrogels using both methods. The applied methods of incorporation influenced the differences in morphology, phase distribution, mechanical and thermal properties, and antimicrobial activity against Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), Proteus mirabilis (ATCC 12453), and Candida albicans (ATCC 10231). Composite material can be recommended for further development and application in environments that are suitable for diseases spreading.

and reduce resource use, we developed new composite materials synthesized regarding green pathways. Bio cellulose hydrogel represents a highly pure polysaccharide biopolymer that various bacterial genera can produce. It has a similar chemical structure as in plants and with high porosity and specific surface area can be successfully used as carrier material. On the other hand, cellulose itself doesn’t have any functional properties. Hydroxyapatite material represents one of the most used materials from the calcium phosphates since it has a high specific surface area and mild antimicrobial activity. The structural properties and chemical stability of hydroxyapatite enable good resistance to microbiological influences, changes in the pH of the environment, and deficient solubility products in physiological conditions. The main mission of this study was to develop functional polymer-ceramic material using green technologies. Obtained material was investigated by XRD method, to obtain phase and structural properties. The FTIR method determined functional groups related to bacterial cellulose and hydroxyapatite. The microstructural properties of the material were determined by the SEM-EDS method. The antibacterial activity of the obtained composite was tested against Gram- positive bacteria Staphylococcus aureus, Lysteria monocytogenes, and Gram-negative bacteria Pseudomonas aeruginosa, Acinetobacter baumanii, by total plate count assay. The microstructural analyses revealed that nanoparticle hydroxyapatite was successfully incorporated into the cellulose hydrogel, resulting in the creation of a new functionalized polymer-ceramic based material. The FTIR results identified vibration groups belonging to cellulose and hydroxyapatite. Additionally, the results of the powder X-ray diffractograms showed broad peaks belonging to cellulose with incorporated hydroxyapatite. Microbiological analyses demonstrated moderate antimicrobial activity of the composite material obtained.

La hidroxiapatita és un mineral de fosfat de calci que constitueix el principal component inorgànic dels ossos i dents, proporcionant rigidesa i duresa a aquestes estructures. La seva importància rau en la seva capacitat per promoure la osteointegració en implants dentals i ortopèdics, la qual cosa facilita la unió directa de l’implant amb l’os, millorant l’estabilitat i funcionalitat a llarg termini. Aquest projecte presenta un estudi exhaustiu sobre la síntesi controlada de nanocomposites d’hidroxiapatita mitjançant plasma, amb l'objectiu de demostrar la seva viabilitat com a mètode ràpid i ambientalment amigable per a la producció de compostos químics i materials avançats. L'objectiu principal és explorar la síntesi i la seva aplicació en la producció d'hidrogels, destacant la recerca de la possible sinergia entre ambdós processos. La metodologia inclou l'estudi de les condicions del plasma per a la síntesi de fosfats de calci, optimitzant el procés per obtenir hidroxiapatita i poder carregar aquestes nanopartícules en hidrogels d'alginat de sodi. Els procediments específics inclouen la preparació de mescles de precursors, la síntesi de fosfats de calci mitjançant plasma en diverses condicions, la caracterització de les mostres sintetitzades mitjançant tècniques com espectroscòpia Raman, espectroscòpia de raigs X d’energia dispersiva, microscòpia electrònica de rastreig o proves de compressió per avaluar les propietats mecàniques i d'absorció dels hidrogels. La investigació ha demostrat que la tecnologia de plasma pot promoure un mètode eficient i sostenible per a la síntesi de nanocomposites de hidroxiapatita, amb aplicacions prometedores en la producció i càrrega d'hidrogels amb aquest fosfat de calci. Aquests avenços podrien suposar un gran pas endavant en el desenvolupament de processos industrials més verds i econòmics., La hidroxiapatita es un mineral de fosfato de calcio que constituye el principal componente inorgánico de los huesos y dientes, proporcionando rigidez y dureza a estas estructuras. Su importancia recae en su capacidad para promover la osteointegración en implantes dentales y ortopédicos, lo cual facilita la unión directa del implante con el hueso, mejorando la estabilidad y funcionalidad a largo plazo. Este proyecto presenta un estudio exhaustivo sobre la síntesis controlada de nanocompuestos de hidroxiapatita mediante plasma, con el objetivo de demostrar su viabilidad como método rápido y ambientalmente amigable para la producción de compuestos químicos y materiales avanzados. El objetivo principal es explorar la síntesis y su aplicación en la producción de hidrogeles, destacando la investigación de la posible sinergia entre ambos procesos. La metodología incluye el estudio de las condiciones del plasma para la síntesis de fosfatos de calcio, optimizando el proceso para obtener hidroxiapatita y poder cargar estas nanopartículas en hidrogeles de alginato de sodio. Los procedimientos específicos incluyen la preparación de mezclas de precursores, la síntesis de fosfatos de calcio mediante plasma en diferentes condiciones, la caracterización de las muestras sintetizadas mediante técnicas como espectroscopia Raman, espectroscòpia de raigs X d’energia dispersiva, microscopia electrónica de rastreo o pruebas de compresión para evaluar las propiedades mecánicas y de absorción de los hidrogeles. La investigación ha demostrado que la tecnología de plasma puede promover un método eficiente y sostenible para la síntesis de nanocompuestos de hidroxiapatita, con aplicaciones prometedoras en la producción y carga de hidrogeles con este fosfato de calcio. Estos avances podrían suponer un gran paso adelante en el desarrollo de procesos industriales más verdes y económicos., Hydroxyapatite is a calcium phosphate mineral that constitutes the primary inorganic component of bones and teeth, providing rigidity and hardness to these structures. Its importance lies in its ability to promote osseointegration in dental and orthopedic implants, facilitating the direct bonding of the implant with the bone, thereby improving long-term stability and functionality. This project presents a comprehensive study on the controlled synthesis of hydroxyapatite nanocomposites using plasma, with the aim of demonstrating its viability as a rapid and environmentally friendly method to produce chemical compounds and advanced materials. The main objective is to explore the synthesis and its application in the production of hydrogels, highlighting the investigation of the possible synergy between both processes. The methodology includes the study of plasma conditions for the synthesis of calcium phosphates, optimizing the process to obtain hydroxyapatite and to be able to load these nanoparticles into sodium alginate hydrogels. Specific procedures include the preparation of precursor mixtures, the synthesis of calcium phosphates using plasma under different conditions, the characterization of the synthesized samples using techniques such as Raman spectroscopy, Energy dispersive X-ray spectroscopy, scanning electron microscopy, and compression tests to evaluate the mechanical properties and absorption of the hydrogels. The research has demonstrated that plasma technology can promote an efficient and sustainable method for the synthesis of hydroxyapatite nanocomposites, with promising applications in the production and loading of hydrogels with this calcium phosphate. These advances could represent a significant step forward in the development of greener and more economical industrial processes.

BACKGROUND Digital radiography has been used to evaluate the progress of bone growth with a collagen-hydroxyapatite implant in rabbit tibias. This study aimed to introduce digital radiography methods that provide comprehensive data availability for continuous information retrieval from the implant preparation to the cultivation period. METHODS 38 digital radiographs were divided into 3 treatment groups, namely a single defect without implant (control), single-implant, and three-implant. Radiographic acquisitions were performed at preparation time and post-implantation from 0 to 56 days. Observations were concentrated on the implantation site, followed by creating a lateral profile. The prediction of implantation growth was determined using relative bone density (RBD) percentage. RESULTS Based on the profile, the recovery process consisted of implant absorption and new bone tissue deposition. The absorption process was highly influenced by the defect size. In the control and single-implant groups, regardless of the different recovery processes, similar recovery results were observed 56 days post-implantation, with an RBD value of approximately 90%. Meanwhile, the three-implant group only had an RBD value of 62%. CONCLUSIONS Radiography can evaluate absorption and new bone growth during implantation in New Zealand white rabbits. Radiographs, which can be obtained at any time during cultivation, offered more information on the recovery implantation process than the other method that relies on data obtained after sacrificing the animals.

Screw-bone construct failures are a true challenge in orthopaedic implant fixation, particularly in poor quality bone. Whilst augmentation with polymeric or ceramic bone cement can improve the primary stability of the screws, the cement may block the flow of blood and nutrients and hamper bone remodelling. In this study, soft, non-setting biomaterials based on Hyalectin gels and hydroxyapatite (HA) particles with different morphological parameters were evaluated as potential augmentation materials, using a lapine ex vivo bone model. The pull-out force, stiffness, and work to fracture were considered in evaluating screw attachment. The pull-out force of constructs reinforced with Hyalectin containing irregularly shaped nano-HA and spherically shaped micro-HA particles were found to be significantly higher than the control group (no augmentation material). The pull-out stiffness increased for the micro-HA particles and the work to fracture increased for the irregular nano-HA particles. However, there were no significant augmentation effect found for the spherical shaped nano-HA particles. In conclusion, injectable Hyalectin gel loaded with hydroxyapatite particles was found to have a potentially positive effect on the primary stability of screws in trabecular bone, depending on the HA particle shape and size.

In this work, we propose hydroxyapatite (HA) as a hard template to unlock the porosity of Fe-N-C catalyst materials. Using HA, a naturally occurring mineral that can be removed with nitric acid, in the synthesis generates a catalyst material with a unique porous network comprising abundant pores and interparticle cavities ranging from 10 to 3000 nm. Hard templating with HA alongside ZnCl2 as a micropore former results in a Fe-N-C catalyst based on naturally abundant peat with excellent oxygen reduction activity in alkaline conditions. A half -wave potential of 0.87 V vs RHE and a peak power density of 1.06 W cm-2 were achieved in rotating ring disk electrode and anion exchange membrane fuel cell experiments, respectively, rivaling the performance of other state-of-the-art platinum-free catalysts presented in the literature. A combined approach of using renewable peat as a carbon source and HA as a hard template offers an environmentally friendly approach to high-performance Fe-N-C catalysts with abundant porosity., QC 20240110

Nowadays the bone conditions have been a meaning clinical challenge and solutions are limited, sometimes ineffective. Hydroxyapatite investigation (main bone component) has gained significant importance. In this research, was analyzed the calcium precursor effect on structural and microstructural properties of hydroxyapatite comparing results of hydroxyapatite obtained from a natural source. Through the solution combustion synthesis were synthesized hydroxyapatite powders using calcium carbonate extracted from eggshell and commercial calcium carbonate and calcium nitrate. As well the natural source of hydroxyapatite was bovine bone which was washed, fractured and heat treatment. The functional groups were obtained by infrared spectroscopy and the crystalline phases by X-ray diffraction. Transmission electron microscopy allowed to determine the particle spherical morphology produced from calcium carbonate (eggshell) with the smallest size (∼20-50 nm) while those obtained by commercial precursors presented nonhomogeneous morphology. The results showed that the respective process followed was efficient to get hydroxyapatite nanoparticles obtained from calcium carbonate at temperature of 1100ºC. Calcium carbonate from eggshells allowed getting HAp whose morphology was homogeneous with nanometric size., Debido a que en la actualidad las afecciones óseas siguen siendo un desafío clínico significativo y las soluciones son limitadas y en algunos casos poco efectivas, la investigación alrededor de la hidroxiapatita, principal componente mineral del hueso ha cobrado una importancia relevante.En este trabajo de investigación se analizó el efecto del precursor de calcio en las características estructurales y microestructurales de la hidroxiapatita, comparando los resultados obtenidos con hidroxiapatita extraída de una fuente natural. Mediante el método de reacción por combustión en solución fueron sintetizados polvos de hidroxiapatita utilizando como precursores de calcio carbonato de calcio extraído de la cáscara de huevo y carbonato y nitrato de calcio comerciales. A su vez, la fuente natural de hidroxiapatita fue hueso bovino, que se sometió a un proceso de lavado, fractura y tratamiento térmico. Los grupos funcionales presentes en las muestras obtenidas fueron determinados mediante espectroscopia infrarroja y las fases cristalinas mediante difracción de rayos-X. La microscopía electrónica de transmisión permitió determinar la morfología esférica de las partículas obtenidas a partir de carbonato de calcio (de cáscara de huevo) con el menor tamaño de partícula (entre 20 y 50 nm); mientras que, las obtenidas a partir de precursores comerciales presentaron una morfología no homogénea. Los resultados mostraron que el proceso seguido fue eficiente para la obtención de nanopartículas de hidroxiapatita cuando se obtiene a partir de carbonato de calcio y a una temperatura de 1100ºC. El carbonato de calcio proveniente de la cáscara de huevo permitió obtener hidroxiapatita con morfología homogénea y tamaño nanométrico.

Guided Bone Regeneration (GBR) is the choice of treatment for improving the horizontal and vertical bone volume through bone grafting. GBR membranes work on the principle of preventing epithelial migration into the defect space while maintaining the space for cell migration and differentiation at the defect site. Hydroxyapatite has been commonly used as a bone graft for infrabony defects. The study was conducted at the Department of Biomaterials at Saveetha Dental College. GBR membrane was prepared and its material characterization was done using Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX) analysis, Fourier Transform Infrared Radiation (FTIR), and Confocal Analysis. The developed GBR membrane revealed SEM properties conducive to cell attachment. EDX and FTIR analysis showed the successful development of the collagen-gelatin-hydroxyapatite membrane. Cell culture and confocal analysis revealed excellent biocompatibility with a homogenous layer of viable cells. The developed composite GBR membrane is a biogenic membrane with relevant biomineralization potential that should be applied for GBR applications., La regeneración ósea guiada (GBR) es el tratamiento de elección para mejorar el volumen óseo horizontal y vertical mediante injertos óseos. Las membranas GBR funcionan según el principio de prevenir la migración epitelial hacia el espacio del defecto. La hidroxiapatita se ha utilizado habitualmente como injerto óseo para defectos infraóseos. El estudio se realizó en el Departamento de Biomateriales del Saveetha Dental College. Se preparó un scaffold o andamio, el cual se caracterizó mediante microscopio electrónico de barrido (SEM), análisis de rayos X de dispersión de energía (EDAX), radiación infrarroja por transformada de Fourier (FTIR) y análisis confocal. El andamio desarrollado reveló propiedades propicias para la unión celular. Los análisis EDAX y FTIR mostraron el desarrollo exitoso de la membrana de colágeno-gelatina-hidroxiapatita. El cultivo celular y el análisis confocal revelaron una excelente biocompatibilidad con una capa homogénea de células viables. El andamio desarrollado es una membrana biogénica con un potencial de biomineralización relevante que puede utilizarse para aplicaciones GBR.

Objectives This study aimed to evaluate the intensity of the subacute local biological effects after implantation and osseoconductive potential of novel hydroxyapatite-based bone substitute coated with poly (lactide-co-glycolide), named ALBO-OS, in comparison to Bio-Oss®. Methods Fifteen male Wistar rats, randomly assigned into groups: 10, 20, and 30 days (n꞊5), were subcutaneously implanted with ALBO-OS and Bio-Oss®. Furthermore, artificially made bone defects on both rat’s tibias were implanted with experimental materials. Unimplanted defects represented negative control. After the animals’ euthanizing, tissue samples were prepared and analyzed histologically and histomorphometrically. Results Normal healing of the epithelial tissue was observed, with no signs of infection or necrosis. Minimal vascular congestion was noted immediately around the graft, with no signs of tissue oedema, with a minimal capsule thickness. The applied material did not cause an inflammatory response (IR) of significant intensity, and 20 days after implantation, the IR was mainly assessed as minimal. The tibial specimen showed that ALBO-OS has good osseoconductive potential, similar to Bio-Oss®, as well as low levels of acute and subacute inflammation. Conclusions The tested material exhibits satisfying biocompatibility, similar to Bio-Oss®.

This study aimed to compare the biological properties of newly synthesized cements based on calcium phosphate with a commercially used cement, mineral trioxide aggregate (MTA). Strontium (Sr)-, Copper (Cu)-, and Zinc (Zn)-doped hydroxyapatite (miHAp) powder was obtained through hydrothermal synthesis and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive X-ray spectrometry (EDX). Calcium phosphate cement (CPC) was produced by mixing miHAp powder with a 20 wt.% citric acid solution, followed by the assessment of its compressive strength, setting time, and in vitro bioactivity. Acetylsalicylic acid (ASA) was added to the CPC, resulting in CPCA. Biological tests were conducted on CPC, CPCA, and MTA. The biocompatibility of the cement extracts was evaluated in vitro using human dental pulp stem cells (hDPSCs) and in vivo using a zebrafish model. Antibiofilm and antimicrobial effect (quantified by CFUs/mL) were assessed against Streptococcus mutans and Lactobacillus rhamnosus. None of the tested materials showed toxicity, while CPCA even increased hDPSCs proliferation. CPCA showed a better safety profile than MTA and CPC, and no toxic or immunomodulatory effects on the zebrafish model. CPCA exhibited similar antibiofilm effects against S. mutans and L. rhamnosus to MTA.

Nitrogen and phosphorus pollution is still a serious environmental problem and a major threat to sustainable development, as they mainly cause eutrophication. Therefore, increasingly stricter requirements are placed on wastewater treatment plants when it comes to emissions of nutrients. To meet these requirements, it is important to continuously renew and improve the purification processes, thereby reducing the emissions of nutrients to the sea, lakes, and streams. The effect of simultaneous nitrogen removal and phosphorus recycling was investigated in this study, employing a one-step process for partial nitritation/anammox-hydroxyapatite (PN/HAP). An experiment in a laboratory-scale SBR reactor (Sequence Batch Reactor) was performed using wastewater from the side-stream centrate. This study validated results to a certain extent published studies by other researchers. However, they had almost exclusively used synthetic wastewater, unlike the here presented where real wastewater was used. The innovative PN/A-HAP process showed effective nitrogen and phosphorus removal without additional aeration or pH adjustment, which means lower energy consumption, reduced nitrous oxide emissions, and reduced sludge production. The results showed an average nitrogen removal efficiency of 32.84% and an average phosphorus removal efficiency of 71.48%. These results indicate significant potential for sustainable wastewater management for some nitrogen and phosphorus side streams at the treatment plants. However, further research is required on a larger scale to precisely assess the long-term separation efficiency for nitrogen and phosphorus, as well as the scalability and usability of the process under real conditions. This Thesis was performed in the frame of a research project 'Process development of CA-induced HAP (Hydroxyapatite) granulation in nitrogen separation with Anammox' funded by the VA Cluster Mälardalen., Kväve- och fosforföroreningar är fortfarande ett allvarligt miljöproblem och ett stort hot mot en hållbar utveckling, eftersom de främst orsakar övergödning. Därför ställs allt strängare krav på avloppsreningsverken när det gäller utsläpp av näringsämnen. För att uppfylla dessa strängare krav är det viktigt att kontinuerligt förnya och förbättra reningsprocesserna och därigenom minska utsläppen av näringsämnen till hav, sjöar och vattendrag. I denna studie undersöktes effekten av samtidig kväveavskiljning och fosforåtervinning från avloppsvatten med hjälp av en enstegsprocess för partiell nitritering/Anammox-Hydroxyapatit (PN/HAP). Ett experiment i laboratorieskala genomfördes med hjälp av en SBR-reaktor (sequence batch reactor) för behandling av avloppsvatten från sidoströmscentrat. Denna studie validerade delvis resultat från andra forskares publicerade studier.Dessa hade dock nästan uteslutande använt syntetiskt avloppsvatten till skillnad från den här presenterade där riktigt avloppsvatten användes. Den innovativa PN/A-HAP-processen visade effektiv kväve- och fosforavskiljning utan behov av ytterligare luftning eller pH-justering, vilket i praktiken betyder lägre energiförbrukning, minskade lustgasutsläpp och minskad slamproduktion. Resultaten visade en genomsnittlig kväveavskiljningseffektivitet på 32,84% och en genomsnittlig fosforavskiljningseffektivitet på 71,48%. Dessa resultat tyder på en betydande potential för hållbar avloppsvattenhantering för vissa kväve- och fosforrika sidoströmmar vid reningsverken. Det krävs dock ytterligare forskning i större skala för att exakt kunna bedöma den långsiktiga avskiljningseffektiviteten för kväve och fosfor, samt processens skalbarhet och användbarhet under verkliga förhållanden. Denna artikel är skriven som en del av ett forskningsprojekt 'Processutveckling av Ca-inducerad HAP (hydroxyapatit) granulering vid kväveavskiljning med anammox' finansierat av VA-kluster Mälardalen.

The interconnection of three-dimensional (3D) printing, material science, and bone tissue engineering holds immense promise in the realm of scaffold development for bone repair. This work delves into the intricate interplay between various factors influencing the success hydroxyapatite biomaterials in bone regeneration, including material selection, porosity, structural design, surface modification, and other mechanical characteristics. Our aim is the pursuit of ideal biomaterials possessing both favorable biological responses and mechanical integrity. Fourier transform infrared spectroscopy (FTIR) is used to analyze the chemical structure of the material, particularly the chemical bonds present. Using SEM, we were subsequently able to analyze the microstructure and nanostructure of the 3D printed hydroxyapatite sample.

Hydroxyapatite-based materials have been widely used in countless applications, such as bone regeneration, catalysis, air and water purification or protein separation. Recently, much interest has been given to controlling the aspect ratio of hydroxyapatite crystals from bulk samples. The ability to exert control over the aspect ratio may revolutionize the applications of these materials towards new functional materials. Controlling the shape, size and orientation of HA crystals allows obtaining high aspect ratio structures, improving several key properties of HA materials such as molecule adsorption, ion exchange, catalytic reactions, and even overcoming the well-known brittleness of ceramic materials. Regulating the morphogenesis of HA crystals to form elongated oriented fibres has led to flexible inorganic synthetic sponges, aerogels, membranes, papers, among others, with applications in sustainability, energy and catalysis, and especially in the biomedical field., This project has received funding from the European Research Council (ERC), grant agreement number 101055053 (BAMBBI). Maria-Pau Ginebra acknowledges the support received through the ICREA Academia Award for excellence in research, funded by the Generalitat de Catalunya. Montserrat Espanol acknowledges the support from Generalitat de Catalunya through the Serra Hunter program, and Anna Diez-Escudero acknowledges the Spanish Ministry of Universities for the support received through the Maria Zambrano fellowship., Peer Reviewed, Postprint (published version)

This study aimed to (1) comparatively analyze properties of Sr- and Mg-substituted hydroxyapatite (HAP)-based dental inserts; (2) evaluate insert bonding to restorative materials, and (3) evaluate the effect of doped HAP inserts on fracture resistance (FR) of human molars with large occlusal restorations. By ion-doping with Sr or Mg, 3 insert types were obtained and characterized using XRD, SEM, Vickers hardness and fracture toughness. Shear bond strength (SBS) was determined between acid etched or unetched inserts and following materials: Maxcem cement (Kerr); Filtek Z250 (3M) bonded with Single Bond Universal (SBU; 3M) or Clearfil Universal (Cf; Kuraray). Modified Class I cavities were prepared in 16 intact molars and restored using insert + composite or composite only (control) (n = 8/group). FR of restored molars was determined by static load until fracture upon thermal cycling. Fracture toughness was similar between Sr/Mg-doped inserts (0.94–1.04 MPam 1/2 p = .429). Mg-doped inserts showed greater hardness (range 4.78–5.15 GPa) than Sr6 inserts (3.74 ± 0.31 GPa; p < .05). SBS for SBU and Cf adhesives (range 7.19–15.93 MPa) was higher than for Maxcem (range 3.07–5.95 MPa) (p < .05). There was no significant difference in FR between molars restored with insert-containing and control restorations (3.00 ± 0.30 kN and 3.22 ± 0.42 kN, respectively; p > .05). HAP-based inserts doped with Mg/Sr had different composition and mechanical properties. Adhesive bonding to inserts resulted in greater bond strength than cementation, which may be improved by insert acid-etching. Ion-doped HAP inserts did not affect FR of restored molars. In conclusion, HAP-based dental inserts may potentially replace dentin in large cavities, without affecting fracture resistance of restored teeth.

The slow advance in anticancer drug development can be attributed to the limitations of conventional models, predominantly monolayer cell (2D) cultures and animal models, which inadequately recapitulate the complex nature of human malignant tumors. Three-dimensional (3D) in vitro models are invaluable tools in drug screening; however, creating a universal model for all cancer types poses challenges due to the diverse nature of cancers. The aim of this work was to develop a single, versatile model using alginate microfibers to accommodate cultivation of various cancer cells.

INTRODUCTION: Tissue engineering strives for innovative solutions in addressing challenges associated with contemporary bone tissue implants. This study focuses on the electrophoretic deposition (EPD) of hydroxyapatite-based bioceramic composites containing antibacterial agents onto titanium surfaces. Two composite coatings, hydroxyapatite/ chitosan (HAP/CS) and hydroxyapatite/chitosan/gentamicin (HAP/CS/Gent) were developed to combat issues such as poor adhesion, limited antibacterial potential, limited bioactivity, and potential toxicity of implant materials [1]. EXPERIMENTAL: EPD was performed at constant voltage (5 V, 12 min) on pure Ti plates from aqueous (HAP/CS and HAP/CS/Gent) suspensions. The uniformity and functionality of the deposited coatings were assessed through comprehensive physico-chemical characterization using X-ray diffraction (XRD) (Philips PW 1710, Netherlands) and scanning electron microscopy (SEM, Hitachi S-4700, J) equipped with energy dispersive X-Ray spectroscopy (EDS, X-Max, Oxford Instruments, UK). Antibacterial activity was evaluated against Staphylococcus aureus TL and Escherichia coli ATCC 25922 by quantitatively monitoring changes in the viable number of bacterial cells in suspension. Cytotoxicity against MRC-5 and L929 cell lines was investigated using trypan blue dye-exclusion test (DET) and MTT assay for assessing cell metabolic activity. Statistical significance was determined for antibacterial and cytotoxicity results by one-way analysis of variance (ANOVA), followed by multiple comparisons post-hoc test. RESULTS AND DISCUSSION: XRD revealed broadened diffraction maximums corresponding to fine HAP crystallites. Porous surface with homogeneously distributed spherical HAP agglomerates embedded in wax-like polymers' matrix of CS was observed for both coatings by SEM. The addition of gentamicin significantly enhanced the antibacterial activity of the HAP/CS/Gent coating – complete reduction of S. aureus bacterial cells was achieved

This dissertation explores the multifaceted roles of rare-earth doped hydroxyapatite in biomedical applications, bridging the gap between luminescence studies and osteogenic potential in the context of bone tissue engineering and regenerative medicine. In the second chapter, we look into the luminescence properties of terbium, cerium, and europium doped hydroxyapatite scaffolds when immersed in simulated body fluid (SBF) over a four-week period. Our comprehensive study reveals a consistent decrease in luminescence emission intensity across all samples, accompanied by a reduction in the concentration of rare-earth ions within the scaffolds, as confirmed by energy dispersive spectroscopy. Furthermore, fluorescence spectroscopy demonstrates the translocation of these ions into the SBF, indicating the scaffolds' partial dissolution over time. The employment of rare-earth ions as luminescence markers offers profound insights into apatite formation mechanisms, presenting significant implications for the development of safer and more durable materials in biomedical applications.Expanding upon the foundational knowledge established in the first and second chapters, the third chapter investigates the osteogenic potential of rare-earth doped hydroxyapatite scaffolds using a murine pre-osteoblastic cell line. This study assesses the effects of ytterbium, terbium, cerium, and europium doping on osteoblast differentiation, gauged by alkaline phosphatase activity and the expression of osteogenic marker genes such as Runx2, OCN, ALP, OPN, and BMP2. Our findings indicate a notable enhancement in differentiation activity with the incorporation of rare-earth elements, with europium and ytterbium doped HAp showing superior performance. Cathodoluminescence spectroscopy further corroborates these results by revealing distinct emission peaks specific to the Eu2+/Eu3+ and Yb2+ ions, underscoring the role of valence state incorporation in augmenting osteoblast differentiation. Collectively

Objectives: To assess and compare the cell viability and ion release profiles of two conventional glass ionomer cements (GICs), Fuji IX and Ketac Molar EasyMix, modified with TiO2 and Mg-doped-HAp nanoparticles (NPs). Methods: TiO2 NPs, synthesized via a sol–gel method, and Mg-doped hydroxyapatite, synthesized via a hydrothermal process, were incorporated into GICs at a concentration of 5 wt.%. The biocompatibility of prepared materials was assessed by evaluating their effects on the viability of dental pulp stem cells (DPSCs), together with monitoring ion release profiles. Statistical analysis was performed using One-way analysis of variance, with significance level p < 0.05. Results: The addition of NPs did not significantly affect the biocompatibility of GICs, as evidenced by comparable decreased levels in cell viability to their original formulations. Distinct variations in cell viability were observed among Fuji IX and Ketac Molar, including their respective modifications. FUJI IX and its modification with TiO2 exhibited moderate decrease in cell viability, while other groups exhibited severe negative effects. While slight differences in ion release profiles were observed among the groups, significant variations compared to original cements were not achieved. Fluoride release exhibited an initial “burst release” within the initial 24 h in all samples, stabilizing over subsequent days. Conclusions: The addition of NPs did not compromise biocompatibility, nor anticariogenic potential of tested GICs. However, observed differences among FUJI IX and Ketac Molar, including their respective modifications, as well as induced low viability of DPSC by all tested groups, suggest the need for careful consideration of cement composition in their biological assessments. Clinical significance: The findings contribute to understanding the complex interaction between NPs and GIC matrices. However, the results should be interpreted recognizing the inherent limitations associated

Objectives: The impact of implant surfaces in dental biofilm development is presently unknown. The aim of this investigation was to assess in vitro the development of a complex biofilm model on titanium and zirconium implant surfaces, and to compare it with the same biofilm formed on hydroxyapatite surface. Methods: Six standard reference strains were used to develop an in vitro biofilm over sterile titanium, zirconium and hydroxyapatite discs, coated with saliva within the wells of pre-sterilized polystyrene tissue culture plates. The selected species used represent initial (Streptococcus oralis and Actinomyces naeslundii), early (Veillonella parvula), secondary (Fusobacterium nucleatum) and late colonizers (Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans). The developed biofilms (growth time 1 to 120h) were studied with confocal laser scanning microscopy using a vital fluorescence technique and with low-temperature scanning electron microscopy. The number (colony forming units/biofilm) and kinetics of the bacteria within the biofilm were studied with quantitative PCR (qPCR). As outcome variables, the biofilm thickness, the percentage of cell vitality and the number of bacteria were compared using the analysis of variance. Results: The bacteria adhered and matured within the biofilm over the three surfaces with similar dynamics. Different surfaces, however, demonstrated differences both in the thickness, deposition of the extracellular polysaccharide matrix as well as in the organization of the bacterial cells. Significance: While the formation and dynamics of an in vitro biofilm model was similar irrespective of the surface of inoculation (hydroxyapatite, titanium or zirconium), there were significant differences in regards to the biofilm thickness and three-dimensional structure., Depto. de Especialidades Clínicas Odontológicas, Fac. de Odontología, TRUE, pub

Hydroxyapatite is a biocompatible material with various applications. To meet the demand for industrial use of this material, a rapid and upscalable process for the synthesis of hydroxyapatite nanoparticles was developed using an in-house developed two-stage continuous flow hydrothermal reactor. In the framework of this study, phase pure and highly crystalline 30 to 115 nm long hydroxyapatite nanorods were produced for potential use as nanofertilizers. The phase composition of the nanorods was confirmed by X-ray diffraction. Particle size and shape were investigated using transmission electron microscopy. Inductively coupled plasma mass spectrometry was used to determine the Ca:P ratio. It was shown that the use of a second mixing stage allows the particle length to be decreased down to 30 nm without compromising on crystallinity. In addition to using different mixing stages, adjusting the pH and controlling the flow speed allow wide range size tuning of the produced particles. The experimental setup allows for continuous synthesis of phase pure and highly crystalline hydroxyapatite nanorods, ensuring the reproducibility and scalability of the process. Dispersive behavior and dissolution in citrate buffer at a hydroponic pH of 5.5 were studied to evaluate further possibilities of applying produced NPs on the plants.

The application of 3D printing to calcium phosphates has opened unprecedented possibilities for the fabrication of personalized bone grafts. However, their biocompatibility and bioactivity are counterbalanced by their high brittleness. In this work we aim at overcoming this problem by developing a self-hardening ink containing reactive ceramic particles in a polycaprolactone solution instead of the traditional approach that use hydrogels as binders. The presence of polycaprolactone preserved the printability of the ink and was compatible with the hydrolysis-based hardening process, despite the absence of water in the ink and its hydrophobicity. The microstructure evolved from a continuous polymeric phase with loose ceramic particles to a continuous network of hydroxyapatite nanocrystals intertwined with the polymer, in a configuration radically different from the polymer/ceramic composites obtained by fused deposition modelling. This resulted in the evolution from a ductile behavior, dominated by the polymer, to a stiffer behavior as the ceramic phase reacted. The polycaprolactone binder provides two highly relevant benefits compared to hydrogel-based inks. First, the handleability and elasticity of the as-printed scaffolds, together with the proven possibility of eliminating the solvent, opens the door to implanting the scaffolds freshly printed once lyophilized, while in a ductile state, and the hardening process to take place inside the body, as in the case of calcium phosphate cements. Second, even with a hydroxyapatite content of more than 92%, the flexural strength and toughness of the scaffolds after hardening are twice and five times those of the all-ceramic scaffolds obtained with the hydrogel-based inks, respectively., Peer Reviewed, Postprint (published version)

En aquest estudi, es van utilitzar scaffolds d'hidroxiapatita deficient en calci (CDHA) dopada amb ions, produïdes mitjançant impressió 3D, per a la regeneració òssia. La investigació pretenia caracteritzar mostres de cinc grups diferents: Control, Sr-BM, Sr-Ink, Cu-BM i Ga-BM, després de la implantació in vivo en conills en dos moments, 4 setmanes i 12 setmanes. L'objectiu principal era establir un mètode de quantificació robust per a la regeneració òssia i, posteriorment, obtenir resultats de bastides implantades en defectes del còndil femoral (en ambdós moments) i llocs intramusculars (només a les 12 setmanes). La quantificació es va aconseguir mitjançant el programari Python i Dragonfly per a volums 3D, complementat amb anàlisi histològica amb QuPath per a rodanxes 2D. Els resultats van indicar un rendiment superior de Sr-Ink, mentre que Control, Ga-BM i Sr-BM van mostrar resultats comparables, afavorint marginalment els dos últims. En particular, Cu-BM no va mostrar evidència de regeneració òssia. L'anàlisi ICP de la incorporació i alliberament d'ions va revelar l'alliberament excepcional de calci (Ca) i estronci (Sr) de Sr-Ink. Ga, tot i que present en quantitats més baixes, va demostrar un potencial regeneratiu significatiu, especialment en una mostra intramuscular. De fet, l'anàlisi SEM va mostrar la regeneració òssia mitjançant l'osteoinducció en Sr-Ink (2 mostres) i Ga-BM (1 mostra), sense cap observació en altres grups. Sr-Ink va superar constantment altres grups, possiblement atribuït al seu mètode únic d'incorporació en fase sòlida, donant lloc a un augment de la porositat. Aquest mètode distintiu probablement va facilitar l'alliberament d'ions millorat, augmentant així la regeneració òssia. Per contra, el Cu-BM pot haver patit un contingut excessiu de coure, que podria conduir a la citotoxicitat. En conclusió, aquesta caracterització exhaustiva de les bastides CDHA dopades amb ions destaca el rendiment excepcional de Sr-Ink en diversos paràmetres. Tamb, En este estudio se emplearon scaffolds de hidroxiapatita deficiente en calcio (CDHA) dopada con iones, producidos mediante impresión 3D, para la regeneración ósea. El objetivo de la investigación era caracterizar muestras de cinco grupos distintos: Control, Sr-BM, Sr-Ink, Cu-BM y Ga-BM, tras su implantación in vivo en conejos en dos momentos, 4 semanas y 12 semanas. El objetivo primario era establecer un método de cuantificación robusto para la regeneración ósea y posteriormente obtener resultados de los andamios implantados en defectos del cóndilo femoral (en ambos puntos temporales) y en sitios intramusculares (sólo a las 12 semanas). La cuantificación se logró utilizando el software Python y Dragonfly para los volúmenes 3D, complementado por el análisis histológico con QuPath para los cortes 2D. Los resultados indicaron un rendimiento superior de Sr-Ink, mientras que Control, Ga-BM y Sr-BM mostraron resultados comparables, favoreciendo marginalmente a los dos últimos. Cabe destacar que Cu-BM no mostró indicios de regeneración ósea. El análisis ICP de la incorporación y liberación de iones reveló la excepcional liberación de calcio (Ca) y estroncio (Sr) por parte de la Sr-Ink. El Ga, aunque presente en menores cantidades, demostró un potencial regenerativo significativo, especialmente en una muestra intramuscular. De hecho, el análisis SEM mostró regeneración ósea mediante osteoinducción en Sr-Ink (2 muestras) y Ga-BM (1 muestra), sin que se observara ninguna en otros grupos. Sr-Ink superó sistemáticamente a los demás grupos, posiblemente debido a su exclusivo método de incorporación en fase sólida, que dio lugar a una mayor porosidad. Este método distintivo probablemente facilitó una mayor liberación de iones, impulsando así la regeneración ósea. Por el contrario, el Cu-BM puede haber sufrido un contenido excesivo de cobre, lo que podría haber provocado citotoxicidad. En conclusión, esta exhaustiva caracterización de los andamiajes CDHA dopados con iones pone de, In this study, ion-doped calcium deficient hydroxyapatite (CDHA) scaffolds, produced via 3D printing, were employed for bone regeneration. The research aimed to characterize samples from five distinct groups: Control, Sr-BM, Sr-Ink, Cu-BM, and Ga-BM, following in vivo implantation in rabbits at two time points, 4 weeks and 12 weeks. The primary objective was to establish a robust quantification method for bone regeneration and subsequently obtain results from scaffold implanted in femoral condyle defects (at both time points) and intramuscular sites (only at 12 weeks). Quantification was achieved using Python and Dragonfly software for 3D volumes, complemented by histological analysis with QuPath for 2D slices. Results indicated superior performance from Sr-Ink, while Control, Ga-BM, and Sr-BM exhibited comparable outcomes, marginally favouring the latter two. Notably, Cu-BM did not show evidence of bone regeneration. ICP analysis of ion incorporation and release revealed Sr-Ink's exceptional release of calcium (Ca) and strontium (Sr). Ga, although present in lower quantities, demonstrated significant regenerative potential, particularly in one intramuscular sample. In fact, SEM analysis displayed bone regeneration through osteoinduction in Sr-Ink (2 samples) and Ga-BM (1 sample), with none observed in other groups. Sr-Ink consistently outperformed other groups, possibly attributed to its unique solid-phase incorporation method, resulting in increased porosity. This distinctive method likely facilitated enhanced ion release, thereby boosting bone regeneration. Conversely, Cu-BM may have suffered from excessive copper content, potentially leading to cytotoxicity. In conclusion, this comprehensive characterization of ion-doped CDHA scaffolds highlights Sr-Ink's outstanding performance across various parameters. It also holds potential for the effectiveness of incorporating Ga into scaffolds, given that even a minimal quantity demonstrated significant impact., Incoming

Human bone is a composite material composed of a mineral and organic phase. It is a living tissue that, when damaged, regenerates spontaneously and naturally to allow reconstruction or replacement of lost or damaged bone tissue. In cases of critical-sized bone defects in the maxillofacial region, spontaneous regeneration becomes impossible, necessitating guided bone regeneration (GBR) to reconstruct the defect surrounding dental implants. This surgical procedure involves the use of a bone graft and a barrier membrane to create a suitable environment for new bone cell formation. Despite this widely used process, commercially available GBR membranes exhibit numerous disadvantages and fail to be active in the bone regeneration process. This research project aims to develop an innovative GBR membrane utilizing hydroxyapatite doped with therapeutic ions to enhance its bioactivity. The production of this membrane involves the synthesis of hydroxyapatite ultra-long nanofibres doped with therapeutic ions in order to obtain a flexible and bioactive GBR membrane. The primary focus of the project is to establish a synthesis mechanism for doping hydroxyapatite ultralong nanofibres with strontium, zinc and magnesium. Two distinct mechanisms were employed, both derived from the synthesis of hydroxyapatite ultra-long nanofibres through a hydrothermal treatment of a calcium oleate precursor. The parameters studied during this project encompassed the synthesis time, the content of doping ions and the type of therapeutic ions. The first mechanism, the one-step synthesis, involves mixing all reagents to form a calcium oleate precursor with therapeutic ions, followed by high-temperature and high-pressure hydrothermal treatment. This process successfully yielded Sr-doped hydroxyapatite ultra-long nanofibres. However, further studies are required to assess the extent of doping of the fibres with magnesium and zinc as the introduction of the doping ion into the hydroxyapatite crystal latt, El hueso humano es un material constituido por una fase mineral y otra orgánica. Es un tejido vivo que, cuando se daña, se regenera de forma espontánea y natural para permitir la reconstrucción o sustitución del tejido óseo perdido o dañado. En casos de defectos óseos de tamaño crítico en la región maxilofacial, la regeneración espontánea resulta imposible, por lo que es necesaria la regeneración ósea guiada para reconstruir el defecto que rodea a los implantes dentales. Este procedimiento quirúrgico implica el uso de un injerto óseo y una membrana de barrera para crear un entorno adecuado para la formación de nuevas células óseas. A pesar de tratarse de un proceso ampliamente utilizado, las membranas GBR disponibles en el mercado presentan numerosos inconvenientes y no consiguen ser activas en el proceso de regeneración ósea. Este proyecto de investigación pretende desarrollar una membrana GBR innovadora que utilice hidroxiapatita dopada con iones terapéuticos para mejorar su bioactividad. La producción de esta membrana implica la síntesis de nanofibras ultralargas de hidroxiapatita dopadas con iones terapéuticos para obtener una membrana GBR flexible y bioactiva. El objetivo principal del proyecto es establecer un mecanismo de síntesis para dopar nanofibras ultralargas de hidroxiapatita con estroncio, zinc y magnesio. Se emplearon dos mecanismos distintos, ambos derivados de la síntesis de nanofibras ultralargas de hidroxiapatita mediante un tratamiento hidrotérmico de un precursor de oleato de calcio. Los parámetros estudiados durante este proyecto involucraron el tiempo de síntesis, el contenido de iones dopantes y el tipo de iones terapéuticos. El primer mecanismo, la síntesis en un solo paso, consiste en mezclar todos los reactivos para formar un precursor de oleato de calcio con iones terapéuticos, seguido de un tratamiento hidrotérmico a alta temperatura y alta presión. Este proceso produjo con éxito nanofibras ultralargas de hidroxiapatita dopada con Sr. Si, L'os humain est un matériau composite composé d'une phase minérale et organique. C'est un tissu vivant qui, lorsqu'il est endommagé, se régénère spontanément et naturellement pour permettre la reconstruction ou le remplacement du tissu osseux perdu ou endommagé. Dans les cas de défauts osseux de taille critique dans la région maxillo-faciale, la régénération spontanée devient impossible, ce qui nécessite une régénération osseuse guidée pour reconstruire le défaut afin de pouvoir visser un implant dentaire. Cette procédure chirurgicale implique l'utilisation d'un greffon osseux et d'une membrane barrière afin de créer un environnement propice à la formation de nouvelles cellules osseuses. Malgré ce processus de régénération osseuse guidée, les membranes actuellement disponibles dans le commerce pour la régénération osseuse guidée présentent de nombreux inconvénients et ne parviennent pas à être actives dans le processus de régénération osseuse. Ce projet de recherche vise ainsi à développer une membrane GBR innovante utilisant de l'hydroxyapatite dopée avec des ions thérapeutiques pour améliorer sa bioactivité. Ainsi, la fabrication de cette membrane implique la synthèse de nanofibres d’hydroxyapatite ultra-longues dopées avec des ions thérapeutiques afin d’obtenir une membrane flexible et bioactive. L'objectif principal du projet est d'établir un mécanisme de synthèse pour le dopage des nanofibres ultra-longues d'hydroxyapatite avec du strontium, du zinc et du magnésium. Deux mécanismes distincts ont été utilisés, tous deux dérivés de la synthèse de nanofibres ultra-longues d'hydroxyapatite par traitement hydrothermique d'un précurseur d'oléate de calcium. Les paramètres étudiés au cours de ce projet comprennent le temps de synthèse, la teneur en ions dopants et le type d'ions thérapeutiques. Le premier mécanisme, correspondant à une synthèse en une étape, implique le mélange de tous les réactifs pour former un précurseur d'oléate de calcium avec des ions thérapeuti, Incoming