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International audience; In 2020, Coronavirus disease (COVID-19), a new viral respiratory disease caused by a virus that belongs to Coronaviridae family, has been identified. It is a very severe flu that negatively affects the functions of the lung and other respiratory organs. COVID-19 virus can be transmitted between people either by touching an infected person or by direct contact with their respiratory droplets. Therefore, the COVID-19 virus has become a global concern due to its rapid spread and severity. Based on the World Health Organization report from 2 March 2020 to 24 October 2022, the total infected cases and deaths in Morocco are around 1,265,389 (3.46%) and 16,280 (0.04%), respectively. Recently, some scientists have found that chitosan, a polymer existed in nature, can inhibit COVID-19 infection and repair damaged tissue. Therefore, understanding chitosan mechanisms in controlling COVID-19, might lead to innovative strategies in the medical field, such as developing drugs against SARS-CoV-2, and replacing vaccines, which have negative side effects. This review aims to show the evolution of the COVID-19 pandemic worldwide, specifically in Morocco, its pathophysiology, and its ability to silence the immune system. This review also provides an overview of the treatments and measures applied to protect human beings and how chitosan acts and controls COVID-19

International audience; Calcium phosphate cements (CPC) have been widely investigated as bone substitutes, owing to their attractive features in terms of physicochemical and biocompatibility properties. However, the clinical applicability of this group of biomaterials is still critically limited by its poor strength and rheological properties in terms of injectability and cohesion. The present work aims to develop novel composite cement based on calcium phosphate cement (CPC) and bioactive glass (BG), associated with sodium alginate hydrogel (Alg). The composition, microstructure, setting, rheological, and mechanical properties of this composite cement were further investigated. Evaluation of setting properties showed that BG participates crucially in the setting reaction as a calcium and phosphate provider and serves as a setting accelerator. Thus, the setting time appears lower in these cements than in the reference CPC cement: it decreases from 75 to 42 min as the BG content increases from 10 to 25 wt% and is delayed from 42 to 73 min while the Alg amount augmented from 1 to 5 wt%. The rheological evaluation revealed that injectability was slightly improved with increasing BG content compared to the injectability of CPC, reaching a value close to 100% when combined with Alg hydrogel. The anti-washout property appeared to be weak for the CPC with or without BG, which are disintegrated in solution. The cohesiveness was significantly improved by introducing Alg hydrogel; furthermore, the addition of 5 wt% of alginate hydrogel induced an increase in the compressive strength about twice (7.2 MPa) higher than that of the reference CPC (4.0 MPa). According to the above findings, the addition of BG acts as a setting accelerator leading to a fast apatite formation, while the introduction of Alg hydrogel as a rheological promoting agent improves the injectability and cohesion. The combination of BG and Alg as additives increased the compressive strength compared to the reference cement.

International audience; This work investigates the bioactivity of novel silver-doped (BG-Ag) and gold-doped (BG-Au) quaternary 46S6 bioactive glasses synthesized via a semi-solid-state technique. A pseudo-second-order kinetic model successfully predicted the in vitro uptake kinetic profiles of the initial ion-exchange release of Ca in simulated body fluid, the subsequent Si release, and finally, the adsorption of Ca and P onto the bioactive glasses. Doping with silver nanoparticles enhanced the rate of P uptake by up to approximately 90%; whereas doping with gold nanoparticles improved Ca and P uptake rates by up to about 7 and 2 times, respectively; as well as Ca uptake capacity by up to about 19%. The results revealed that the combined effect of Ca and Si release, and possibly the release of silver and gold ions into solution, influenced apatite formation due to their effect on Ca and P uptake rate and capacity. In general, gold-doped bioactive glasses are favoured for enhancing Ca and P uptake rates in addition to Ca uptake capacity. However, silver-doped bioactive glasses being less expensive can be utilized for applications targeting rapid healing. In vitro studies showed that BG, BG-Ag and BG-Au had no cytotoxic effects on osteosarcoma MG-63 cells, while they exhibited a remarkable cell proliferation even at low concentration. The prepared bioactive glass doped with noble metal nanoparticles could be potentially used in bone regeneration applications.

International audience; Bone tissue engineering is gaining popularity as an alternative method for the treatment of osseous defects. A number of biodegradable polymers have been explored for tissue engineering purposes. A new family of biodegradable polymer/bioactive glass composite materials has been designed to be used in bone regeneration approaches. In this work, a hybrid scaffold of chitosan (CH) and bioactive glass nanoparticles (BGN) was prepared by the freeze-gelation method. This method has been studied by adjusting the concentration of acetic acid; this process can influence the structure properties of the scaffold. In this work, several BGN/CH composites have been prepared by varying the proportion of BGN in the hybrid scaffold (20, 40, 60, and 80%). Brunauer-Emmett-Teller results showed the increased surface area and porosity volume of our composite with decreasing BGN proportion. BGN/CH hybrid scaffold was characterized by using physicochemical techniques. Obtained results showed a macroporous morphology of the scaffold with a pore size of about 200 μm, and a homogeneous distribution of the BGN in the CH matrix. X-ray diffraction study confirmed the amorphous state of the BGN/CH hybrid scaffold. Interaction between CH and BGNs in the composite was confirmed. The in vitro assays showed adequate degradation properties, which is essential for the potential replacement by the new tissue. The in vitro bioactivity studies confirmed the formation of an apatite layer on the surface of the hybrid scaffold, which results in a direct bone bonding of the implant. These results indicate that BGN/CH hybrid scaffold developed is a potential candidate for bone tissue engineering.

International audience; Tissue engineering has emerged as an alternative approach to create bone tissue by growing cells on 3D scaffolding. The aim of this study was to synthesize a composite glass/chitosan (BG-CH) by using new salt leaching using powder (SLUP) process in order to control the porosity rate and then the chemical reactivity of the final product. SLUP process consists on the cavity creation with desired pore sizes. It does not require heat treatment. This process is based on washing out the NaCl particles used for that. It is due to its high solubility in aqueous media. This work focuses on the elaboration, physicochemical, and chemical reactivity studies of pure bioactive glass and bioactive glass associated with chitosan. A range of composite scaffolds with different bioactive glass/chitosan contents has been synthesized. NaCl with a distinct range size was used with the aim of optimizing the pore network. Obtained results show that the specific surface area and pore volume increase with increasing of chitosan and porogen content. The same observations for pore volume were registered. The obtained scaffolds had high porosity (90%) with good pore connectivity. SEM images revealed strong dependence of sizes and shapes of pores on the salt/composite ratios.

International audience; This work aims to develop an injectable and antibacterial composite cement for bone substitution and prevention/treatment of bone infections. This cement is composed of calcium phosphate, calcium carbonate, bioactive glass, sodium alginate, and ciprofloxacin. The effect of ciprofloxacin on the microstructure, chemical composition, setting properties, cohesion, injectability, and compressive strength was investigated. The in vitro drug release kinetics and the antibacterial activity of ciprofloxacin-loaded composites against staphylococcus aureus and Escherichia coli pathogens were investigated. XRD and FTIR analysis demonstrated that the formulated cements are composed of a nanocrystalline carbonated apatite analogous to the mineral part of the bone. The evaluation of the composite cement’s properties revealed that the incorporation of 3 and 9 wt% of ciprofloxacin affects the microstructural and physicochemical properties of the cement, resulting in a prolonged setting time, and a slight decrease in injectability and compressive strength. The in vitro drug release study revealed sustained release profiles over 18 days. The amounts of ciprofloxacin released per day (0.2 -15.2 mg/L) depend on the cement composition and the amount of ciprofloxacin incorporated. The antibacterial activity of ciprofloxacin-loaded cement composites attested to their effectiveness to inhibit the growth of Staphylococcus aureus and Escherichia coli.

This work investigates the bioactivity of novel silver-doped (BG-Ag) and gold-doped (BG-Au) quaternary 46S6 bioactive glasses synthesized

Phosphate glasses, with molar compositions 37.5Na 2 O-25[(1-x)MgO-xNiO]-37.5P 2 O 5 (0 ≤ x ≤ 1), have been prepared using the conventional melt quenching technique. The free nickel glass is colorless while the glasses containing nickel are yellow. The effect of Ni 2+ ions on structural and physico-chemical properties of these glasses has been investigated by XRD, DTA, EPR, Raman, FTIR spectroscopies and by density and chemical durability measurements. Substitution of Ni 2+ for Mg 2+ strengthens the glass network, as shown by the decrease of the molar volume, the increase of the glass transition temperature, and the improvement of the chemical durability. This behavior is a consequence of the replacement of Mg-O bonds by more covalent Ni-O bonds. The glass structure consists of tri-phosphate (P 3 O 10 ) 5- and di-phosphate (P 2 O 7 ) 4- groups, and Mg/NiO 6 octahedra, with Mg-O-P and Ni-O-P linkages.

International audience; This research is based on the study of thermal behaviour of bioactive glass in the quaternary system SiO2-CaO-Na2O-P2O5 doped with metallic elements such as Zn and Sr destined for use as bone biomaterial. It encompasses glass transition temperature, crystallization temperature and melting temperature. This work is based on both determination and comparison of the effects of Zn and Sr on thermal characteristics after their introduction in the glass matrix. Thermal stability and excess entropy of all studied glasses have been calculated. Obtained results highlight the different effects of doping on the glasses thermal behaviour. Most notable effects are the sharp decrease of melting temperature of 10 wt% Zn-doped glass and the increase of crystallization temperature of 10 wt% Sr-doped glass. Furthermore, excess entropy of pure glass increases with addition of Sr and decreases with addition of Zn. © 2018 Elsevier B.V.

This work is devoted to study the reactivity of the quaternary glass 52S4 (52% SiO2–30% CaO–14% Na2O–4% P2O5 (wt%)), synthesized by sol-gel process versus the treatment temperature. The dried gel was heat treated at 600 and 650 °C and soaked in simulated body fluid (SBF). XRD results confirm the amorphous character of glass treated at 600 °C even though the heat treatment at 650 °C induces Na2Ca2Si3O9 formation. After soaking in SBF, SEM and EDS results show the formation of carbonated hydroxyapatite (CHA) at the glass surface for both temperatures. For the glasses treated at 600 and 650 °C, two phenomena were observed: the glass dissolution in SBF and the CHA precipitation, but the reactivity kinetics of glass was different when temperature changes. For SGDG600, the CHA began to crystallize after 16 h. For SGDG650, a glass ceramic made of a glassy matrix and of Na2Ca2Si3O9, the crystallized carbonated HA was observed after 2 h. In addition, a new crystallization at the glass surface of Na2Ca2Si3O9 was observed after 15 days.

International audience; We investigated the effects of Kalach 360 SL (KL), Glyphosate (G)-based herbicide, on bone tissue in different groups of female Wistar rats. Group 1 (n = 6) received a standard diet and served as a control, groups 2 and 3 (n = 6 each) received 0.07 ml (D1 126 mg/Kg) and 0.175 ml (D2 315 mg/Kg) of KL dissolved in the water for 60 days. The plasma was used to examine the metabolic balance markers (calcium, phosphorus, phosphatase alkaline (PAL), and vitamin D (vit D) and hormonal status (oestrogen and thyroid hormones). As a result, sub-chronic exposure to KL induced a perturbation of bone metabolism (calcium and phosphorus) and hormonal status disturbance. The histological and immunohistochemical study of the thyroid gland revealed a disturbance in morphological structure and thyroid cells function. Moreover, the KL disrupting eff ;ect on thyroid function was investigated by measuring changes in plasma levels of thyroid hormones. Free triiodothyronine (FT3) and thyroxine (FT4) were decreased in female rats breast-fed from rats treated with D and D2 of KL. This eff ;ect was associated with an increase in the plasma level of thyroid-stimulating hormone (TSH). Thus, that KL leads to hypothyroidism. Decrease in levels of oestrogen and thyroid dysfunction led to a disruption in the skeletal bone. The histological study and SEM in bone results allowed us to observe, in rats exposed to KL, the thinning and discontinuity of bone trabecular with a significant decrease in the number of nodes (intertrabecular links).In conclusion, KL sub-chronic exposure caused an aspect of osteoporosis.

This work describes a quantitative kinetic approach to assess the in vitro bioactivity of gold-doped hydroxyapatite-polyvinyl alcohol nanocomposites. The surface morphology of the in situ prepared nanocomposites as characterized by transmission electron microscopy (TEM) revealed a rod-like shape. Differential thermal analysis-thermogravimetric (DTA-TG), and fourier transformed infrared spectroscopy (FTIR) as well as zeta potential measurements of the prepared nanocomposites were carried out. Uptake profiles of Ca and P were studied onto nanocomposites of different gold concentrations after their soaking in simulated body fluid and they best followed the pseudo second-order kinetic model. The highest uptakes of both Ca and P were obtained using the nanocomposite with the lowest concentration of gold. Furthermore, sorption mechanism was described by the intraparticle diffusion model where pore diffusion was found to be the rate limiting step. The prepared nanocomposites have promising potential in orthopedic and tissue engineering applications because of their high capacity and fast uptake for Ca and P, which form apatite. (c) 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3483-3492, 2015.

The biomaterials are used for many biomedical applications. The main objective of the present work was to investigate the potential role of Bioglass (Melting)- Polyvinyl alcohol (BG (M)-PVA) and Bioglass (Melting)-Polyvinyl alcohol-20%Ciprofloxacin (BG (M)-PVA-20Cip) in regenerative bone capacity. These composites were implanted in the femoral condyles of Wistar rats and compared to that of ovariectomised groups. Our results noted, after the different period of implantation (15, 30, 60 and 90 days), that the Alkaline phosphatase (ALP) and Acid phosphatase (ACP) activities showed an excellent osteoinductive property of BG (M)-PVA, that this phenomena decreased with the presence of ciprofloxacin. Physico-chemical techniques (ICP-OES and SEM) were engaged to highlight the influence of antibiotic on the structure, porosity and bioactivity of a porous Glass-PVA before and after implantation. The results obtained by ICP-OES showed a rapid reduction in silicon (Si) and sodium (Na), and noted an accelerator increase in calcium (Ca) and phosphorus (P) ion concentrations in BG (M)-PVA that the BG (M)-PVA-20Cip. This result is confirmed by SEM. We can conclude that the loading of ciprofloxacin in BG (M)-PVA is characterized by a retard effect of formation of apatitic phase.

Radiation therapy contributes to a significant increase in bone osteoporosis and skin loss. Various natural health products might be beneficial to reduce bone and skin alterations. Curcumin (CUR) medicines derived from natural plants have played an important role in health care. This study aims at synthesizing and evaluating the performance therapy of CUR-encapsulated bioglass-chitosan (CUR-BG-CH). In vitro, the antioxidant assay was evaluated by using 1,1-diphenyl-2-picrylhydrazyl free-radical (DPPH) scavenging and the nitroblue tetrazolium reduction. The CUR-BG-CH antimicrobial effects were tested in liquid media. In vivo, after rat 60 Co γ-radiation, the tissue wound-healing process was studied by grafting CUR and CUR-BG-CH in femoral condyle and dorsal skin rat tissue. The antioxidant studies indicated that CUR-BG-CH quenches free radicals more efficiently than unmodified CUR and had effective DPPH (91%) and superoxide anion (51%) radical scavenging activities. The CUR-BG-CH biomaterial exhibited an important antimicrobial activity against Staphylococcus aureus. The histomorphometric parameters showed amelioration in CUR-BG-CH-treated rats. An improved mechanical property was noticed (33.16 ± 5.0 HV) when compared with that of unmodified CUR group (23.15 ± 4.9 HV). A significant decrease in tumour necrosis factor-α cytokine production was noted in the CUR-BG-CH rats (90 pg/ml) as compared with that of unmodified CUR group (240 pg/ml). The total amount of hydroxyproline was significantly enhanced (33.5%) in CUR-BG-CH group as compared with that of control. Our findings suggested that CUR-BG-CH might have promising potential applications for wound healing.

The main objective of the present work was to investigate the effect of surfactant chain length on the structure, porosity and bioactivity of 92S6 (92% SiO 2 , 6% CaO, and 2% P 2 O 5 mol%) mesoporous sol–gel glasses. The aim was to provide a basis for controlling the porosity of the glass to obtain a control of bioactive behavior. A series of mesoporous bioactive glasses were synthesized using three different surfactants (C 10 H 20 BrN, C 19 H 42 BrN, C 22 H 48 BrN). Surfactant type dependence on the textural properties, particularly porosity and bioactivity were studied. Results indicate that the bioactivity factors were improved by a short surfactant carbon length.

Precursors for the preparation of Si-CHA (silicon and carbonate substituted hydroxyl-apatite) were added in stoichiometric composition in amounts either 30 or 50 solid wt. % to a solution of gelatin to form hybrid nano-composite scaffolds (B(G/Si-CHA)). Temperature was maintained at 40°C and pH at 8 during the reaction. Glutaraldehyde was added to complete the cross-linking then washed. Thereafter, glycine was added to the product to get rid of any glutaraldehyde remnants. Both, 30 and 50% obtained scaffolds were compared with ones containing the same proportions from previously prepared nano powders of the Si-CHA named (C(G/Si-CHA)). The four types and a control one made of gelatin alone (G) were examined by X-ray diffraction (XRD), infrared spectroscopy (FTIR), transmission and scanning electron microscopy (TEM & SEM) and mercury porosimeter. In vitro study was carried out on the prepared scaffolds by immersing in simulated body fluid (SBF) solution for different periods between 1and 28 days. The change in the percentage of the different ions with time in the solutions was followed. Results of IR showed the reaction of the carboxylic groups of gelatin with the added ingredients giving a homogeneous distribution of the inorganic phase formed (Si-CHA). High porosity reaching 94% was achieved with macro and micro pores without the addition of a porogen material.

Currently, research on biomaterials must meet and demonstrate a set of therapeutic competence to level many health problems. The objective of our work is to normalize the technique of implantation of the biomaterial (carbonated hydroxyapatite: HAC). Three modes subcutaneous implantation was carried out. This technique consists to select the most tolerated by the body without toxicity. Thus, we have applied our biomaterial (HAC) in pellet form under pressure, under pressure sintering pellets and capsules for two weeks. Our results showed that the capsule did not disturb and mainted the equilibrium and balance or ferric ion phosphate balance, prevent against the toxicity of hepato-renal system by comparison with the pellets. These results demonstrated the tolerance, the biocompatibility and the integrity of apatite administered in capsule.

International audience; Recently, oxidative stress has been identified as a pivotal pathological factor inducing bone osteoporosis. This phenomenon is responsible for low bone density. It alters bone quality and generates bone fractures. Strontium is found to induce osteoblast activity by stimulating bone formation and reducing bone resorption by restraining osteoclasts. Bioglass (BG) has been used to repair bone defects, and, in combination with strontium (BG-Sr), offers an opportunity to treat this disease. This study investigated the potential role of BG-Sr in improving antioxidant activity and regenerative bone capacity, The effects of both BG-Sr and BG were tested on osteoblast SaOS2 and endothelial EAhy926 cell proliferation in vitro. In vivo, BG-Sr and BG were implanted in the femoral condyles of Wistar rats and compared to that of control groups. Cell proliferation increased significantly by 120% at SaOS2 and 127% at EAhy926. Superoxide Dismutase (SOD), Catalase (CAT) and Glutathione Peroxidase (GPx) were significantly enhanced in BG-Sr treated rats compared to other groups. Moreover, a significant decrease of thiobarbituric acid-reactive substances (TBARs) was observed. The Ca/P ratio increase improved progressive bone mineralization. According to these results, BG-Sr ameliorated cell proliferation and developed an antioxidative defense against ROS. The histological findings highlight the BG-Sr implications in the osteoporosis treatment confirmed by bone construction. The development of BG-Sr as a therapeutic biomaterial protecting against oxidative stress might make an effective choice for application in tissue engineering.

New sol–gel experimental conditions were tested to prepare a new SiO 2 -based bioactive glass with high Na 2 O content. The aim of this work is to investigate the real influence of the synthesis route (sol–gel versus melting) on the glass intrinsic properties and then, later, on the glass behavior and particularly on bioactivity. The obtained glass and its melt derived counterpart were characterized from structural and morphological (porosity, specific surface area) point of view. It could be noticed that the synthesis mode has no significant influence on glass structure. Conversely, the synthesis mode greatly influences the glass texture. The sol–gel derived glass exhibits a greatly higher specific surface area and pore volume than melt derived glass. This parameter may be a key factor of glass bioactivity.

Calcium phosphate coatings on Ti6Al4V substrates are elaborated by pulsed electrodeposition. The surface morphology and chemical composition of the coatings are characterized by SEM-EDS. The obtained results are systematically confirmed at the nanometre scale using TEM. Moreover, XRD is performed in order to identify the coatings phases. The results show that pulsed electrodeposition allows uniform coatings to be obtained without the holes and craters usually observed with classical electrodeposition. After appropriate heat treatment, these coatings have a biphasic composition of stoichiometric hydroxyapatite and β-tricalcium phosphate. Moreover, the addition of 9% H 2 O 2 to the electrolyte leads to monophasic coatings made of stoichiometric hydroxyapatite. As an indication of the passive nature of the electrodeposited coating, electrochemical potentiodynamic tests are performed in physiological solution in order to determine the corrosion behaviour of these coatings.

OBJECTIVES: Nanoparticles from implanted materials are reported as the main cause of implant failure. Monocytes are among the first cells to colonize the inflammatory site. We evaluated the biological effects of bone substitutes presented to U937 cells in vitro as micron- or nanometer-sized particles. METHODS: The HA (550 nm) and beta-TCP (550 nm) nanoparticles were incubated with U937 cells. Cell cycle modification, specific antigens expression, and the extent of cell death were determined. RESULTS: Firstly, by using the sulforhodamine B (SRB) test and the annexin V-FITC analysis by flow cytometry, our results provide evidence of the absence of cytotoxicity, and show that nanoparticles do not induce more apoptosis than microparticles in U937 cells. Secondly, although morphologic evidence of stimulation of U937-cells was found by confocal microscopy, neither bone substitute altered the distribution of the cells into different phases of the cell cycle (Kit Cycle Test Plus DNA). These results suggest that nanoparticles do not cause promonocyte maturation in macrophages. Thirdly, the flow cytometry results showed no differences in the expression of the adherence and activation markers. SIGNIFICANCE: The results suggest that nanoparticles do not promote the differentiation of promonocytic U937 cells into macrophages and do not induce an enhanced inflammatory response.

Polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) were used to prepare polymeric matrix composites of nanohydroxyapatite (HAV and HAP), respectively, by using a biomimetic approach under 100 °C. A comparison with synthetic nanohydroxyapatite prepared by precipitation (SHA) was evaluated. Characterization of the prepared powders by differential thermal analysis (DTA) and thermogravimetric analysis (TGA) was achieved, X-ray diffraction (XRD), scanning electron microscope (SEM) with elemental analysis by (EDS) and inductively coupled plasma-optical emission spectrometer were used. DTA and TG showed the weight loss in the 400–1200 °C was almost attributed to carbonate decomposition which appeared apparently in the polymer associated samples due to the decomposition of polymer matrix. X-ray diffraction confirmed mainly the formation of hydroxyapatite. Specific surface area (BET) and scanning electron microscope and scanning electron microscopy (SEM) confirmed the range of nanosized of the prepared HA samples. The polymer matrix prefers orientation of the particles to rod-like shape. Elemental analysis showed mainly, Ca, P, C and O ions besides Na and Cl. Inductively coupled plasma showed the composition and the Ca/P atomic ratio of all samples ranging between 1.72 and 1.85.

Bioactive glasses in the system SiO2–CaO–Na2O–P2O5 were synthesized pure and doped with magnesium or zinc by melt-derived method. The bioactivity was studied during in vitro assays: the ability of hydroxycarbonate apatite (HCA) layer to form on the glass surface was examined after contact with simulated body fluid (SBF). The X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) studies were performed before and after immersion in vitro assays. The SBF solutions were also analyzed using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Introduction of magnesium and zinc as trace element induces several modifications on the observed phenomena at the glass surface and in SBF solution after immersion of the samples. The chemical durability of the glasses, the formation of the silica-rich layer and the crystallization of the HCA layer were affected, but not present the same modifications as the introduced doping element.

Porous mixtures of aluminosilicate/calcium phosphate have been studied for biomaterials applications. Aluminosilicates formed with an inorganic polymeric constitution present amorphous zeolites because of their 3D network structure and present the ability to link to bone matrix. Amorphous geopolymers of the potassium–poly(sialate)–nanopolymer type were synthesised at low temperature and studied for their use as potential biomaterials. They were mixed with 13% weight of calcium phosphate like biphasic hydroxyapatite and β-tricalcium phosphate. In this study, “in vivo” experiments were monitored to evaluate the biocompatibility, the surface and the interface behaviour of these composites when used as bone implants. Moreover, it has been demonstrated using histological and physicochemical studies that the developed materials exhibited a remarkable bone bonding when implanted in a rabbit's thighbone for a period of 1 month. The easy synthesis conditions (low temperature) of this composite and the fast intimate links with bone constitute an improvement of synthetic bone graft biomaterial.

This work is focused on the bioactive glasses obtained by melting and rapid quenching. Two glasses with mineral composition of: 47% SiO2 - 26% CaO - 21% Na2O - 6% P2O5 and 48% SiO2 - 30% CaO - 18% Na2O - 4% P2O5 were investigated. The aim of this study was to establish the kinetics of HCAp layer formation “in vitro” and to control the adhesion and proliferation cells of the two glasses in contact with osseous cells. Obtained results permit to evaluate their chemical reactivity and their bioactivity after immersion in the SBF-K9. Ionic exchanges between biomaterials and SBF liquid during the “in vitro” experiments highlight the differences of the chemical reactivity and bioactivity of 47S6 and 48S4. The structural basis for the effect of cristallinity on the rates of HCA formation in vitro in favour of glasses was also established. The melt derived 47S6 and 48S4 glasses offer to surgeons new compositions with different bioactivity kinetic that bioglassÒ 45S6 and can be adaptable in some other bony pathology.

Bioactive ceramics such as bioactive glasses, calcium carbonate and sintered hydroxyapatite are widely used in biomaterials field because of their high biocompatibility. In this study, natural hydroxyapatite (N-HA) and synthetic Hydroxyapatite (S-HA) were heat treated at 800°C and studied using “in vitro” experiments. Several physicochemical methods like: SRD, FTIR, SEM and ICP-OES were employed to evaluate the effects of the thermal treatment and to compare their behaviour after soaking in the Simulated Body Fluid SBF at different times. The formation of TCP has favours the formation of new phase. Obtained results show that the dissolution occurred more in N-HA than in S-HA and consequently the precipitation of new phosphate phase is more important in N-HA. This is due to the presence of Mg, Sr and Zn in N-HA with concentration higher to that in S-HA.

A new glass formulation, with the molar composition 60% SiO 2 –35% CaO–5% P 2 O 5 , was synthesized using the sol–gel process, for applications as biomaterial in orthopaedic or maxillo facial surgery. Pellets, made of glass powder, were uniaxially compacted and soaked in simulated body fluid (SBF) for up to 7 days at 37 °C to evaluate glass bioactivity. Ionic exchanges at the interface glass-SBF were evaluated by studying evolutions of calcium, phosphorus and silicon concentrations in SBF using ICP-OES. Changes in glass surface, and the formation of crystalline phases were analyzed using XRD, SEM, EDS and FTIR methods. Results form ICP-OES showed a high reactivity of the glass surface with a very high and continuous release of calcium, a limited glass dissolution and an uptake of phosphorous from SBF. Results from both FTIR and XRD analysis indicated that the glass surface was progressively covered by two different phases: CaCO 3 as calcite and a carbonated apatite layer. The formation of these phases, following two different schemas, was observed after 2 h of immersion and confirmed after 7 days. SEM micrographs and EDS analysis demonstrated that the main phase, a carbonated apatite, was present as micro-spheroids and the secondary phase, calcite, was materialized by agglomerates which have diameters up to 10–15 μm. These results are in accordance with a bioactive feature of the glass studied.

International audience; Different bioactive glass systems have been prepared by sol-gel. However, the production of Na2O-containing bioactive glasses by sol-gel methods has proved to be difficult as the sodium nitrate used in the preparation could be lost from the glass structure during filtration and washing. The aim of this study was to prepare the quaternary system 46S6 of bioactive glass by modified sol-gel techniques with a decrease in the time of gelation. In addition, compare the behaviour of the prepared sol-gel bioactive glass system by its corresponding prepared by melting. The obtained glasses were characterized by using several physicochemical techniques; XRD, FTIR, TEM and SEM beside the effect of the glass particles on the viability of osteoblast like cells (Saos-2). Results show that nanopowders 40-60 nm of 46S6 glass system had been prepared by modified sol-gel (acid-base reaction) method at 600°C in just three days at 600°C. Cell viability by MTT assay confirmed the effectiveness of the prepared nanobioactive glass.

Bony grafts are used as a filling biomaterial for defective bone. The introduction of new range of synthetic materials offers to surgeons additional possibilities to avoid virus transmission risks by using natural grafts in bony surgery. In this work, two materials, synthetic calcium carbonate and composite aluminosilicate/calcium phosphate were synthesized by an original method and experimented “in vivo” as biomaterials for bony filling. Extracted biopsies were studied by several physico chemical and biological methods. The aim was to evaluate the kinetic resorption and bioconsolidation of these materials. We focused on the bioconsolidation between implant and bone by realising cartographies from the implant to the bone and on the calcification mechanism by determination of the origin of Ca and Sr responsible of the neo-formed bone. Neutron activation analysis (NAA), radiotracers 45Ca* and 85Sr* and proton-induced X-ray emission (PIXE) were used. Concerning the synthetic calcium carbonate, results show that twelve months after implantation, the mineral composition of implant becomes similar to that of the mature bone. The neoformed bone is composed with Ca and Sr coming from the organism when the Ca and Sr of the implant were progressively eliminated. Concerning the composite geopolymer/calcium phosphate, PIXE and histological studies reveal the intimate links between the bone and the implant starting with the first month after implantation.

We have re-examined the evolution of orthorhombic cell parameters as a function of the substitution parameter x in solid solutions Sr {sub x}Ca{sub 1-x}CO{sub 3} in order to clarify contradictory results found in the literature. Calcium carbonate has been synthesized in the presence of Sr{sup 2+} ions (Sr/Ca molar ratio ranging from 10{sup -2} to 1), using experimental conditions that previously allowed us to obtain monophasic aragonite. The precipitates obtained have been analysed using powder X-ray diffractometry (XRD) and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The powder XRD data confirm the occurrence of purely monophasic strontian-aragonites. Moreover, the cell parameters as well as the substitution parameter x have been refined for 0 < x < 0.5 against powder XRD data through Rietveld refinement. On the other hand, x was deduced from chemical analysis by ICP-AES. The agreement between both techniques is very satisfactory. The evolution of the cell parameters as a function of x is found to be linear within the studied range, this feature being confirmed for the overall domain (0 {

Aluminosilicate materials synthesized at room temperature present good mechanical properties. Hydroxyapatite, tricalcium phosphate or both offer a high biocompatibility in the biomedical field. In this work, we focused on the composites resulting from associations of these materials. The best compromise between porosity and biomechanical properties versus different parameters was determined. The in vitro behaviour of compounds in contact with the simulated body fluid (SBF) was studied and in vivo experiments in a rabbit's thighbones were carried out. The inductively coupled plasma-optical emission spectroscopy (ICP-OES) method permitted us to study the eventual release of Al from composites to SBF and to evaluate the chemical stability of composites characterized by the succession of SiO(4) and AlO(4) tetrahedra. The kinetic biomineralization, the bioconsolidation and biological studies were made. The results obtained show the chemical stability of composites. In the bone-implant interface, the intimate links reveal the high quality of the biointegration and the bioconsolidation between composites and bony matrix. Histological studies confirm good bony bonding and highlight the total absence of inflammation or fibrous tissues.

In the field of biomaterials applied in bony restoration, systems based on amorphous silicate network present the ability to link to bone matrix. Amorphous geopolymers of the potassium-poly(sialate)-nanopolymer type with a mole ratio Si:Al = 31 were studied for their use as potential biomaterials. This implied a heat treatment at 500 °C in order to reduce the alkalinity of the geopolymer matrix from pH 11.5 to pH 7.1 and to provide high porosity for biological compatibility. 27Al and 29Si MAS NMR spectroscopy has been used to characterise the foamed geopolymers obtained after different thermal treatments at 250 and 500 °C, and with three different mole ratios K2O/SiO2 for the potassium silicate: 0.54; 0.67 and 0.84. Best results in terms of biological compatibility were obtained with a geopolymer matrix resulting from a mole ratio K2O/SiO2. of 0.54, heat-treated at 500 °C.

In biomaterial field, the introduction of new types of composites presents a great interest for orthopaedic surgeons. In this work, geopolymers which are a family of aluminosilicates were synthesised and mixed with biphasic mixture (hydroxyapatite and of tricalcic phosphate). The optimised thermal treatment causes the reduction of pH to 7 units and favours the expansion of composites. Consequently, the increasing of porosity percentage was induced. These properties offer a good opportunity for applied composite as potential osseous biomaterial. To study the consequences of thermal treatment in the initial amorphous structure of composites some physico-chemical techniques like SEM, MAS-NMR and FTIR were employed. These methods permitted to evaluate the porosity, different links in composites and contributions of different groups of Si and Al before and after thermal treatment.

Composites studied in this work are the associations of aluminosilicates and 13% of calcium phosphates. These composites present great interest. They are destined to be applied in biomedical field, particularly in orthopedic or jawbone surgery. Calcium phosphates are composed of HA (hydroxyapatite) and TCP (tricalcic phosphate). The success of synthesised bony biomaterials depends on two determinant factors: the porosity (which facilitate the cells deposition and the vascularisation) and the compressive strength (which permits the support of body charge). In this way, a statistical experimental design was employed to quantify the influence of these two synthesis parameters. It concerns the effect of the K 2 O/SiO 2 molecular ratio ( X 1 ) and the effect of the calcium phosphate (HA/TCP) weight % ( X 2 ). The K 2 O/SiO 2 molecular ratio characterises the synthesis of the aluminosilicate. It varies between two limit levels: the stoichiometric ratio K 2 O/SiO 2 = 0.54 corresponding to: and the ratio K 2 O/SiO 2 = 0.80 corresponding to . In bony biomaterials field, various calcium phosphates are commonly used as biomaterials. In our previous works, the influence of the commercial hydroxyapatite HA and tri-calcium phosphate TCP (13 wt%) addition was investigated. To study the effect of calcium phosphate composition, the weight percentage of mixing HA and TCP varied between two levels: the composite aluminosilicate with 13 wt% of HA () and the composite aluminosilicate with 13 wt% of TCP (). Eight samples were studied. The statistical experimental design predicted answer surfaces for compressive strength and percentage of porosity. After the validation of models, it was possible to determine composite which presents best compromise between percentage of porosity and compressive strength. This composite will be evaluated by “in-vitro” and “in-vivo” studies to investigate its potential for forthcoming applied as biomaterial.

In orthopaedic surgery, synthetic biomaterials encountered a great success. In this work, the “in-vivo” behaviour of aragonite synthesized in our laboratory was studied. The in vivo experiments have been carried out on femurs sites of nine ovine. Neutron activation analysis was applied to evaluate the ossification kinetics of synthetic aragonite. The content of several elements (Ca, P, Sr and Mg and phosphorous to calcium ratio) were determined versus time after implantation. Results showed that the biomaterial undergoes a lot of transformations during time. The chemical composition of the aragonite was modified and progress to become close to that of an ovine bone. Biological studies assess its biocompatibility.

This study aimed to investigate the potential effects of a synthetic apatite (carbonated hydroxyapatite) on the detoxification of a group of male "Wistar" rats exposed to nickel chloride.Toxicity was evaluated by rats' bioassay of nickel chloride. Wistar rats received this metal daily by gavage for seven days (4 mg/ml nickel chloride/200 g body weight, BW). To detoxify this organism, a subcutaneous implantation of the apatite is made.The results revealed that exposure to nickel induced oxidative stress, disorders in the balances of ferric phosphocalcic, renal failures, liver toxicity and significant increase in nickel rates in the bones of intoxicated rats. The application of the carbonated hydroxyapatite presented in this study restored those disorders back to normal. The synthetic apatite protected the rats against the toxic effects of nickel by lowering the levels of lipid peroxidation markers and improving the activities of defense enzymes. It also amended ferric and phosphocalcic equilibriums, protected liver and kidney functions and reduced the nickel rate in the bones of the rats. Overall, the results provided strong support for the protective role of carbonated hydroxyapatite in the detoxification of rats exposed to nickel. Those beneficial effects were further confirmed by physico-chemical characterization (X-ray diffraction and infrared spectroscopy), which revealed its property of anionic and cationic substitution, thus supporting its promising candidacy for future biomedical application.The hydroxyapatite is an effective biomaterial to solve health problems, particularly detoxification against metals (nickel).

New composite materials based on aluminosilicate materials were developed to be used in orthopaedic or maxillo-facial surgery. They are called geopolymers or polysialate-siloxo (PSS) and were studied alone or mixed with hydroxyapatite (HAP). The properties of these materials were investigated for potential use in biological or surgery applications. In this work, the chemistry involved in materials preparation was described. Samples were characterized by some physico-chemical methods like X-ray diffraction (XRD), infrared spectrometry (IR) and electron dispersion X-ray spectrometry (EDX). Results indicate that the mixing hydroxyapatite-geopolymer (PSS) leads to a neutral porous composite material with interesting physico-chemical properties. A preliminary evaluation of its cytotoxicity reveals an harmlessness towards fibroblasts. These properties allow to envisage this association as a potential biomaterial.

This work investigates the effect of adding silver nanoparticles (NPs) in ppm on the bioactivity of hydroxyapatite/polyvinyl alcohol nanocomposites (HAV). HAV prepared by an in situ biomimetic approach was doped with different concentrations of silver NPs (HAV-Ag), and the formed powder samples were characterized by different techniques such as Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-EOS), X-ray diffraction, transmission electron microscope, and Fourier Transform Infrared Spectroscopy. Bioactivity was evaluated in simulated body fluid through studying the kinetics of Ca and P uptake onto the different HAV-Ag nanocomposites. Uptake profiles of Ca and P were well described by a pseudo-second order kinetic model, and the obtained kinetic parameters confirmed that the highest uptake capacities were achieved by adding less than 0.001 ppm of silver NPs which is an amount not detectable by ICP. Furthermore, HAV-Ag nanocomposites were shown to be non-toxic as well as have a strong antibacterial effect. Silver NPs significantly enhanced the bioactivity of HAV nanocomposites and thus the developed nanocomposites promise to be excellent biomaterials for bone and reconstructive surgery applications. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 4609–4615, 2014.

International audience; Summary Recently, the therapeutic approaches of the detoxification against the metals (nickel) in the body are the use of biomaterials such as carbonated hydroxyapatite. The aim of this study is therefore to analyze the physiological and physicochemical parameters of strain white rats "Wistar" receiving nickel chloride and to study the protective associative of apatite against adverse effects of this metal, and this in comparison with control rats. Our results showed that the nickel induced in rats an oxidative stress objectified by elevated levels of thiobarbituric acid-reactive substances and conjugated dienes associated with inhibition of the activity of the antioxidant defense system such as glutathione peroxidase, superoxide dismutase and catalase in the liver, kidney, spleen and erythrocyte. Disorders balances of ferric, phosphocalcic, a renal failure and a liver toxicity were observed in rats exposed to nickel. As well as a significant increase in the rate of nickel in the bones and microcytic anemia was revealed. However, the implantation of carbonated hydroxyapatite in capsule form protects rats intoxicated by the nickel against the toxic effects of this metal by lowering the levels of markers of lipid peroxidation and improving the activities of defense enzymes. Our implantation technique is effective to correct ferric balance and phosphocalcic equilibrium, to protect liver and kidney function, to reduce the rate of bone nickel and to correct anemia. They clearly explain the beneficial and protective of our biomaterial which aims the detoxification of rats receiving nickel by substituting cationic (Ca2+ by Ni2+) and anionic (OH− by Cl−) confirmed by physicochemical characterization like the IR spectroscopy and X-ray diffraction. These techniques have shown on the one hand a duplication of OH− bands (IR) and on the other hand the increase of the volume of the apatite cell after these substitutions (X-ray diffraction).

Critical-sized bone defects have, in many cases, posed challenges to the current gold standard treatments. Bioactive glasses are reported to be able to stimulate more bone regeneration than other bioactive ceramics; however, the difficulty in producing porous scaffolds made of bioactive glasses has limited their extensive use in bone regeneration. On the other hand, calcium phosphate ceramics such as synthetic hydroxyapatite and tricalcium phosphate are widely used in the clinic, but they stimulate less bone regeneration. This paper gives an overview of the recent developments in the field of bioactive nanoparticles, with a focus on nanohydroxyapatite and bioactive glasses for bone repair and regeneration. First, a brief overview of the chemical structure and common methods used to produce synthetic nanohydroxyapatite and bioactive glasses has been presented. The main body of the paper covers the physical and biological properties of these biomaterials, as well as their composites with biodegradable polymers used in bone regeneration. A summary of existing challenges and some recommendations for future directions have been brought in the concluding section of this paper.

This work investigates the effect of adding silver nanoparticles (NPs) in ppm on the bioactivity of hydroxyapatite/polyvinyl alcohol nanocomposites (HAV). HAV prepared by an in situ biomimetic approach was doped with different concentrations of silver NPs (HAV-Ag), and the formed powder samples were characterized by different techniques such as Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-EOS), X-ray diffraction, transmission electron microscope, and Fourier Transform Infrared Spectroscopy. Bioactivity was evaluated in simulated body fluid through studying the kinetics of Ca and P uptake onto the different HAV-Ag nanocomposites. Uptake profiles of Ca and P were well described by a pseudo-second order kinetic model, and the obtained kinetic parameters confirmed that the highest uptake capacities were achieved by adding less than 0.001 ppm of silver NPs which is an amount not detectable by ICP. Furthermore, HAV-Ag nanocomposites were shown to be non-toxic as well as have a strong antibacterial effect. Silver NPs significantly enhanced the bioactivity of HAV nanocomposites and thus the developed nanocomposites promise to be excellent biomaterials for bone and reconstructive surgery applications.

Bioactive glasses, doped with traces of copper (Cu) and zinc (Zn) were synthesized by fusion method. Cu and Zn present interesting functions for the biological metabolism through their antibacterial, anti-inflammatory and antifungal properties. Several physical methods were employed to characterize the bioactive glasses before and after immersion in a Simulated Body Fluid (SBF). The “in vitro” experiments showed that after soaking in SBF, the behavior of bioactive doped glasses are different compared to pure glass 46S6. Obtained results show that glass matrix undergoes some changes after 15 days of immersion. The non toxic character of doped glasses was confirmed after 24 hours of incubation. The kinetic of release of Cu and Zn was carried out. It highlights that Cu is more released than Zn. By SEM, the morphology of hydroxyapatite obtained with Zn-doped glass show a better crystallization compared to Cu-doped glass.

Composite scaffolds of Polyvinyl Alcohol (PVA) and/or quaternary bioactive glass (46S6 system) containing 5, 10 and 20 wt % ciprofloxacin were prepared by lyophilisation technique. The porosity of the prepared scaffolds was measured by liquid displacement, Hg-porosimeter and SEM. The structure and the nature of chemical bonds between atoms were examined by XRD and FTIR. They confirmed the incorporation of ciprofloxacin into the scaffolds. Biodegradation rate and drug release behaviour were conducted in Phosphate Buffer Saline (PBS) at pH 7.4. A porous scaffold has been obtained with porosity up to 85%. By increasing the glass contents and drug concentration in the prepared scaffold the porosity and the degradation rate decrease however, the compressive strength was enhanced. A sustained drug release pattern was observed from the optimized scaffold with a quasi-Fickian diffusion mechanism and it was able to deliver the drug in a prolonged release pattern which offers a distinguish treatment for osteomylitis as well as local antibacterial effect.

Developmental pathology, accidents, and tumor resection frequently cause bone loss,1,2 which is still a problem in orthopedic and reconstructive surgery. To resolve these problems, autografts and allografts have long been used to fill bone defects caused by surgery, trauma or disease.3 Autografts have the advantage of being biocompatible, osteoconductive and osteoinductive. These tissue grafts require additional surgery, which can cause trauma and donor site morbidity that leads to an increase in surgical time and hospital costs.4 Allografts overcome these problems, but can potentially introduce the risk of transmission infection or provoke an immunogenic response. To overcome these problems, a variety of osteoconductive biomaterials such as ceramics and titanium alloys have been considered as bone graft substitutes.5 Titanium (Ti), which is bioinert, does not bond directly but has close contact with bone. Other synthetic bone grafts are made from biphasic calcium phosphates, and beta-tricalcium phosphate, calcium polyphosphate, hydroxyapatite (HA),6 and carbonated hydroxyapatite (CHA). Recently, osteoconductive biomaterials suggest that they can be made in greater quantities and present no immunogenic concerns.7 These biomaterials have gained much attention, not only due to its ionic composition similar to bones but also due to its functional properties favorable for bone growth such as resorbability by living cells.8 Moreover, some investigators have reported that HA is useful as an osteoporosis model. The present study was undertaken to evaluate the regenerative effects of both CHA and mini external fixator in large cortical defect. The utilization of these materials as bone grafts may reduce the need for autogenous bone graft, increase stability of the implant, lead to faster bone regeneration and facilitate the healing process.

International audience; The evaluation of innovative bone substitutes requires the development of an optimal model close to physiological conditions. An interesting alternative is the use of an immortalized cell line to construct multicellular spheroids, that is, three-dimensional (3D) cultures. In this study, a modified hanging drops method has resulted in the generation of spheroids with a well-established human fetal osteoblasts line (hFOB 1.19), and tests have been focused on the effect of 45S5 bioglass ionic dissolution products in comparison with two-dimensional (2D) cultures. Depending on cell culture type, quantitative analysis (cell proliferation, viability/cytotoxicity, and cellular cycle) and qualitative analysis (electron microscopy and genes expression) showed a differential effect. Cell proliferation was enhanced in 2D-conditioned cultures in accordance with literature data, but decreased in 3D cultures submitted to the same conditions, without change of gene expression patterns. The decrease of cell proliferation, observed in conditioned spheroids, appears to be in agreement with clinical observations showing the insufficiency of commercially available bioglasses for bone repairing within nonbearing sites, such as periodontal defects or small bone filling, in general. Therefore, we suggest that this model could be adapted to the screening of innovative bioactive materials by laboratory techniques already available and extended monitoring of their bioactivity.

In this work, the in vivo behaviour of pure aragonite and vectabone, which is an association of aragonite and an active substance such as gentamicin, was studied to highlight the kinetic resorption of these two biomaterials with 55% of porosity destined for the filling or replacement of bony defects. The synthesis conditions and parameters we used permit us to obtain a biomaterial without a sintering stage. These conditions allow introducing of active substances at the first stage of the elaboration. In this work, the gentamycin antibiotic was associated with calcium carbonate (aragonite 55% with gentamycin) to deliver this active substance on the surgical site for local treatment. The tricalcium phosphate biomaterial was used as the control because of its high biocompatibility. The bony remodelling of these three biomaterials was studied by in vivo experiments. This study was ensured with neutron activation analysis (NAA). The resorption kinetic was elaborated and comparisons of the remodelling biomaterials CaCO(3) 55% and CaCO(3) 55% with gentamicin (vectabone) and tricalcium phosphate were carried out. The obtained results show that, 6 months after implantation, the mineral composition of vectabone and tricalcium phosphate becomes close to that of young bone. Twelve months after implantation, it becomes similar to that of mature bone.

Melt-derived glasses in the system SiO(2)-CaO-Na(2)O-P(2)O(5) were synthesized pure or doped with magnesium from 0.4 to 1.2 wt %, for applications as biomaterials in bony surgery. This chemical element has been chosen because of its high physiological interest. Its introduction for different contents in melt derived glasses has never been studied. The bioactivity of glasses was assessed by immersion of the samples in the simulated body fluid solution. Changes in glass surface morphology and composition after immersion were evaluated by several physico-chemical techniques. The aim of this work was to characterize the formation of the apatite-like layer at the glass surface, after in vitro assays and to evaluate the kinetic reaction between the glass and the surrounding synthetic fluids. Results indicate that magnesium influences the formation and the evolution of the newly formed layers: (1) it promotes the dissolution of the silica network, (2) it increases the thickness of the silica gel layer formed conventionally prior to the apatite-like layer, and (3) it slows down the crystallization of the apatite layer. However, the intensity of these effects depends on the content of magnesium introduced in the glass matrix.

Reactive oxygen species are widely considered to be a causal factor of osteoporosis. Bioceramics have been used experimentally and clinically for filling bone defect. This study aims to characterize the oxidative stress biomarker and the antioxidant enzyme profiles during bone regeneration. Wistar rats were divided into: control group (T) ovariectomised (OVX), implanted tissue with porous and Zinc doped bioactive glass (PG) and implanted with Strontium-doped bioactive glass (BG-Sr). Grafted bone tissues were removed to measure malondialdehyde (MDA) concentration, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase activities (GPx). Our results showed that 60 days after surgery, BG-Sr groups presented a higher concentration of MDA as compared to that of PG group. However, the SOD, CAT and GPx in PG group showed higher activities when compared with those of BG-Sr group. These results suggest that 60-day period was sufficient to re-establish oxidant-antioxidant balance accompanied by bone repair.