Carbonated Hydroxyapatite Research Articles

Study of mineralization of lithium calcium phosphosilicate glass ceramics in vivo during bone tissue regeneration

Prospective directions for the creation of biologically active substitutes for bone tissue were analyzed. The effectiveness of the use of calcium phosphosilicate materials modified with CuO, ZnO, Ag2O, Fe2O3, TiO2, SrO and Nb2O5 to ensure high biocompatibility and antibacterial properties of bone endoprostheses has been established. The prospective use of lithium calcium phosphate silicate glass ceramics for obtaining strengthened, biologically active bone implants was substantiated. The main criteria for the development of biocompatible glass-ceramic materials regarding their composition, structure, texture, and surface properties have been established. The influence of differences in the structure and resorption of calcium phosphosilicate glass ceramics on the mechanism of formation of an apatite-like layer in vivo was analyzed. The features of mineralization of calcium phosphosilicate glass ceramics in vivo during bone tissue regeneration were determined, and the effectiveness of the use of glass ceramics based on hydroxyapatite and lithium disilicate in bone tissue replacement was established to reduce the rehabilitation period and long-term use of endoprostheses under variable loads. The developed OS-7 calcium phosphosilicate glass-ceramic material is characterized by the content of crystalline phases of 10 vol.% lithium disilicate and 55 vol.% hydroxyapatite with a ratio of CaO/P2O5=1.67, surface microrelief of 6 m, surface free energy value of 75 mJ/m2 and crack resistance of 6.0 MPam1/2. This material is biocompatible due to the formation of carbonate hydroxyapatite crystals already on the 14th day, which allows us to consider its promising use in the treatment of fractures, defects of long bones and in the replacement of short or tubular bones.

Application of chitosan-gelatin-carbonate hydroxy apatite scaffold toward the number of osteoblasts in alveolar bone defects in Wistar Rats

Tooth extraction may cause bone defects that require regenerative therapy. Chitosan, gelatin, and carbonate hydroxyapatite can help increase osteoblast proliferation and differentiation, which plays a role in the bone regeneration process. Scaffold made from chitosan-gelatin carbonate hydroxyapatite has promising characteristics that may help enhance the bone regeneration process. This study aimed to determine the effect of chitosan-gelatin carbonate hydroxyapatite (CG:CHA) scaffold application towards the number of osteoblasts on alveolar bone defect in Wistar rats after tooth extraction. In vivo experimental laboratory research conducted with post-test-only control group design. The Wistar rats were divided into 6 groups, tooth extraction was conducted, and in the treatment group the C-G:CHA scaffold was applied on the sockets afterward. After 7, 14, and 21 days of scaffold application, jaw resection was done to observe the number of osteoblasts by HE histological examination. The result data were analyzed using a one-way ANOVA test. Data analysis using one-way ANOVA test results in P=0 (P <0,05) which indicates a significant difference between the control and treatment groups. The chitosan-gelatin carbonate hydroxyapatite (C-G:CHA) scaffold can increase the number of osteoblasts.

First principal observation documenting the three-dimensional uptake of cadmium and spatial distribution of cadmium hydroxyapatite mineral in bone char

The 3-D matrix scale ion-exchange mechanism was explored for high-capacity cadmium (Cd) removal using bone chars (BC) chunks (1–2 mm) made at 500 °C (500BC) and 700 °C (700BC) in aqueous solutions. The Cd incorporation into the carbonated hydroxyapatite (CHAp) mineral of BC was examined using a set of synchrotron-based techniques. The Cd removal from solution and incorporation into mineral lattice were higher in 500BC than 700BC, and the diffusion depth was modulated by the initial Cd concentration and charring temperature. A higher carbonate level of BC, more pre-leached Ca sites, and external phosphorus input enhanced Cd removal. The 500BC showed a higher CO32-/PO43- ratio and specific surface area (SSA) than the 700BC, providing more vacant sites by dissolution of Ca2+. In situ observations revealed the refilling of sub-micron pore space in the mineral matrix because of Cd incorporation.The X-ray nanodiffraction (XND) analyses revealed that Cd was mainly removed from water by incorporation into the mineral lattice of 500BC via ion exchange, rather than surface sorption and precipitation, and the mineral phase was transformed from hydroxyapatite (HAp) to cadmium hydroxyapatite (Cd-HAp). The Rietveld's refinement of X-ray diffraction (XRD) data resolved up to 91% of the crystal displacement of Ca2+ by Cd2+. The specific phase and stoichiometry of the new Cd-HAp mineral was dependent on the level of ion exchange. This mechanistic study confirmed that 3-D ion exchange was the most important path for heavy metal removal from aqueous solution and immobilization in BC mineral matrix, and put forward a novel and sustainable remediation strategy for Cd removal in wastewater and soil clean-up.

Polyvinylpyrrolidone-Alginate-Carbonate Hydroxyapatite Porous Composites for Dental Applications.

An alternative approach for the currently used replacement therapy in dentistry is to apply materials that restore tooth tissue. Among them, composites, based on biopolymers with calcium phosphates, and cells can be applied. In the present work, a composite based on polyvinylpyrrolidone (PVP) and alginate (Alg) with carbonate hydroxyapatite (CHA) was prepared and characterized. The composite was investigated by X-ray diffraction, infrared spectroscopy, electron paramagnetic resonance (EPR) and scanning electron microscopy methods, and the microstructure, porosity, and swelling properties of the material were described. In vitro studies included the MTT test using mouse fibroblasts, and adhesion and survivability tests with human dental pulp stem cells (DPSC). The mineral component of the composite corresponded to CHA with an admixture of amorphous calcium phosphate. The presence of a bond between the polymer matrix and CHA particles was shown by EPR. The structure of the material was represented by micro- (30-190 μm) and nano-pores (average 8.71 ± 4.15 nm). The swelling measurements attested that CHA addition increased the polymer matrix hydrophilicity by 200%. In vitro studies demonstrated the biocompatibility of PVP-Alg-CHA (95 ± 5% cell viability), and DPSC located inside the pores. It was concluded that the PVP-Alg-CHA porous composite is promising for dentistry applications.

Synthesis and Characterization of Carbonate Hydroxyapatite from <i>Pinctada Maxima</i> Shell with Short Aging Time for Bone Biomaterial Candidate

Biomaterial products for bone repair are needed to support accelerated tissue healing. This research aimed to synthesize and characterize carbonate hydroxyapatite (CHA) from Pinctada maxima (P. maxima) using the precipitation method with a short aging time, 15 min. CHA was dried with oven-dry at 100°C for 12 h (CHA A) and a furnace-dry at 1000°C for 2 h (CHA B). Short aging time succeeded in producing CHA B-type with lattice parameters and of CHA A is 9.382 and 6.964 , while 9.451 and 6.962 for CHA B. The high temperature treatment made the diffraction peak indicating CHA more detected and crystallinity increased to 97.87%. The appearance of C–O bond and diffraction peaks of CHA verified substituted carbonates hydroxyapatite.

The compressive strength and static biodegradation rate of chitosan-gelatin limestone-based carbonate hydroxyapatite composite scaffold

Background: One of the main components in tissue engineering is the scaffold, which may serve as a medium to support cell and tissue growth. Scaffolds must have good compressive strength and controlled biodegradability to show biological activities while treating bone defects. This study uses Chitosan-gelatin (C–G) with good flexibility and elasticity and high-strength carbonate hydroxyapatite (CHA), which may be the ideal scaffold for tissue engineering. Purpose: To analyze the compressive strength and static biodegradation rate within various ratios of C–G and CHA (C–G:CHA) scaffold as a requirement for bone tissue engineering. Methods: The scaffold is synthesized from C–G:CHA with three ratio variations, which are 40:60, 30:70, and 20:80 (weight for weight [w/w]), made with a freeze-drying method. The compressive strengths are then tested. The biodegradation rate is tested by soaking the scaffold in simulated body fluid for 1, 3, 7, 14, and 21 days. Data are analyzed with a one-way ANOVA parametric test. Results: The compressive strength of each ratio of C–G:CHA scaffold 40:60 (w/w), 30:70 (w/w), and 20:80 (w/w), consecutively, are 4.2 Megapascals (MPa), 3.3 MPa, 2.2 MPa, and there are no significant differences with the p= 0.069 (p>0.05). The static biodegradation percentage after 21 days on each ratio variation of C–G:CHA scaffold 40:60 (w/w), 30:70 (w/w), and 20:80 (w/w) is 25.98%, 24.67%, and 20.64%. One-way ANOVA Welch test shows the result of the p-value as p<0.05. Conclusion: The compressive strength and static biodegradation of the C–G:CHA scaffold with ratio variations of 40:60 (w/w), 30:70 (w/w), and 20:80(w/w) fulfilled the requirements as a scaffold for bone tissue engineering.

Structural Changes in Ceramic Carbonized Hydroxyapatite as a Result of Long-Term Storage at Room Temperature

Carbonated hydroxyapatite (CHA) is the basic mineral component of animal and human bone. Therefore, it is widely used in medicine to repair bone defects. In orthopedic surgeries, ceramic implants are usually used as a biologically active defect filler. In the lattice of CHA carbonate ions can occupy two non-equivalent positions - A and B. A position corresponds to the position of OH- anions in the lattice of hydroxyapatite (HA), and B - PO43-. It is well known that substitution of B-positions with carbonate groups leads to significant distortions of HA lattice, which causes microstresses and crystalline defects in it. Therefore, CHA ceramics as a result of sintering is characterized by significant internal stresses whose relaxation at room temperature can lead to a change in both its phase composition and biological activity. By methods of chemical and X-ray structural analysis, infrared spectroscopy and electron scanning microscopy the ageing process of pressed CHA at room temperature, sintered in an atmosphere of dry carbon dioxide at temperatures 800÷1200 °C was studied. The phase composition and structure of freshly prepared and aged for two years ceramic samples were compared. It is shown that relaxation of internal stresses arising during sintering of presses causes plastic deformation of crystallites accompanied by redistribution of carbonate ions from B to A-position. As a result, displacement of OH- ions from channel (A) positions and decomposition of B-type CHA on CaO and A-type CHA becomes energetically advantageous.

Two-dimensional solid-state NMR spectroscopy investigations of surface precipitation of phosphate onto calcite

The interaction of phosphate with typical soil minerals is important for understanding P cycling in natural and agricultural systems. We investigated the mechanisms of kinetics of phosphate uptake onto calcite using solid-state NMR spectroscopy. At a low phosphate concentration of 0.5 mM, the 31P single-pulse solid-state NMR peak revealed the formation of amorphous calcium phosphate (ACP) within the initial 30 min, which transformed to carbonated hydroxyapatite (CHAP) after 12 d. At a high phosphate concentration (5 mM), the results showed transformation from ACP to OCP, later to brushite, and eventually to CHAP. The formation of brushite is further supported by 31P{1H} heteronuclear correlation (HETCOR) spectra via a correlation of δP–31 = 1.7 ppm and the 1H peak at δH–1 = 6.4 ppm, which denotes the structure water of brushite. Furthermore, 13C NMR directly revealed both A-type and B-type CHAP. Generally, this work provides a detailed understanding of the aging effect on the phase transition scale of phosphate surface precipitation onto calcite in soil environments.

Polyvinylpyrrolidone Nanofibers Incorporating Mesoporous Bioactive Glass for Bone Tissue Engineering.

Composite biomaterials that combine osteoconductive and osteoinductive properties are a promising approach for bone tissue engineering (BTE) since they stimulate osteogenesis while mimicking extracellular matrix (ECM) morphology. In this context, the aim of the present research was to produce polyvinylpyrrolidone (PVP) nanofibers containing mesoporous bioactive glass (MBG) 80S15 nanoparticles. These composite materials were produced by the electrospinning technique. Design of experiments (DOE) was used to estimate the optimal electrospinning parameters to reduce average fiber diameter. The polymeric matrices were thermally crosslinked under different conditions, and the fibers' morphology was studied using scanning electron microscopy (SEM). Evaluation of the mechanical properties of nanofibrous mats revealed a dependence on thermal crosslinking parameters and on the presence of MBG 80S15 particles inside the polymeric fibers. Degradation tests indicated that the presence of MBG led to a faster degradation of nanofibrous mats and to a higher swelling capacity. The assessment of in vitro bioactivity in simulated body fluid (SBF) was performed using MBG pellets and PVP/MBG (1:1) composites to assess if the bioactive properties of MBG 80S15 were kept when it was incorporated into PVP nanofibers. FTIR and XRD analysis along with SEM-EDS results indicated that a hydroxy-carbonate apatite (HCA) layer formed on the surface of MBG pellets and nanofibrous webs after soaking in SBF over different time periods. In general, the materials revealed no cytotoxic effects on the Saos-2 cell line. The overall results for the materials produced show the potential of the composites to be used in BTE.

Bioactive glass for periodontal regeneration: a systematic review

BackgroundOne of the major clinical challenges of this age could be represented by the possibility to obtain a complete regeneration of infrabony defects. Over the past few years, numerous materials and different approaches have been developed to obtain bone and periodontal healing. Among all biomaterials, bioglasses (BG) are one of the most interesting due to their ability to form a highly reactive carbonate hydroxyapatite layer. Our aim was to systematically review the literature on the use and capability of BG for the treatment of periodontal defects and to perform a meta-analysis of their efficacy.MethodsA search of MEDLINE/PubMed, Cochrane Library, Embase and DOSS was conducted in March 2021 to identify randomized controlled trials (RCTs) using BG in the treatment of intrabony and furcation defects. Two reviewers selected the articles included in the study considering the inclusion criteria. The outcomes of interest were periodontal and bone regeneration in terms of decrease of probing depth (PD) and gain of clinical attachment level (CAL). A network meta-analysis (NMA) was fitted, according to the graph theory methodology, using a random effect model.ResultsThrough the digital search, 46 citations were identified. After duplicate removal and screening process, 20 articles were included. All RCTs were retrieved and rated following the Risk of bias 2 scale, revealing several potential sources of bias. The meta-analysis focused on the evaluation at 6 months, with 12 eligible articles for PD and 10 for CAL. As regards the PD at 6 months, AUTOGENOUS CORTICAL BONE, BIOGLASS and PLATELET RICH FIBRIN were more efficacious than open flap debridement alone, with a statistically significant standardized mean difference (SMD) equal to -1.57, -1.06 and − 2.89, respectively. As to CAL at 6 months, the effect of BIOGLASS is reduced and no longer significant (SMD = -0.19, p-value = 0.4) and curiously PLATELET RICH FIBRIN was more efficacious than OFD (SMD =-4.13, p-value < 0.001) in CAL gain, but in indirect evidence.ConclusionsThe present review partially supports the clinical efficacy of BG in periodontal regeneration treatments for periodontal purposes. Indeed, the SMD of 0.5 to 1 in PD and CAL obtained with BG compared to OFD alone seem clinically insignificant even if it is statistically significant. Heterogeneity sources related to periodontal surgery are multiple, difficult to assess and likely hamper a quantitative assessment of BG efficacy.

Effect of solvents and pH on in situ formation of hydroxyapatite for stone conservation

In situ formation of hydroxyapatite (HAP) inside the cracks and on the surface of calcareous substrates (e.g. marble and limestone) has been proposed for consolidation and protection of cultural heritage. HAP can be formed in situ by reacting the substrate with an aqueous solution of diammonium hydrogen phosphate (DAP). Taking inspiration from literature on bioceramics and from recent computational results, in the present study different strategies were explored to improve the consolidating efficacy of the DAP solution, namely by increasing pH or by adding organic solvents. A 1 M DAP +1 mM CaCl2 solution was taken as a reference and compared to 10-fold more diluted solutions (0.1 M DAP + 0.1 mM CaCl2) at pH 8, 10 or 12 and with addition of 20 wt% ethanol, isopropanol, or acetone. The solutions were applied onto weathered marble specimens and the formation of the new phases was characterized by FEG-SEM and XRD, while the strengthening ability was assessed in terms of bulk mechanical properties and surface properties. The results of this study indicate that apatite phases (mostly likely carbonate HAP with possible stoichiometric HAP) were formed as the result of all treatments, except at pH 12 when undesired ammonium calcium phosphate hydrate was formed. In terms of strengthening efficacy, when in-depth consolidation is needed, the more concentrated DAP solutions are able to provide higher strengthening ability. When consolidation of the most superficial layer is desired, less concentrated solutions are able to provide satisfactory results, allowing for a substantial reduction in the use of DAP with economic and environmental advantages.

A short note on bioglass in Periodontics.

Bone augmentation grafts may act as space-maintaining devices to allow coronal migration of periodontal progenitor cells. The ideal bone replacement graft should be able to trigger osteogenesis, cementogenesis and formation of a functional periodontal ligament. It has been theorized that bioactive glass, which is a ceramic has bioactive properties that guide and promote osteogenesis allowing rapid formation of bone. Bioactive glass consists of sodium and calcium salts, phosphates and silicon dioxide for dental applications. When this material comes into contact with tissue fluids, the surface of the particles becomes coated with hydroxy carbonate apatite, incorporates organic ground proteins such as chondroitin sulfate and glycosaminoglycans and attracts osteoblasts that rapidly form bone.

Enhancement of Fracture Toughness in carbonate doped Hydroxyapatite based nanocomposites: Rietveld analysis and Mechanical behaviour

Highly nanocrystalline carbonated hydroxyapatite (CHAp) is synthesized by hydrothermal technique with four different stoichiometric compositions for microstructural and mechanical analysis. HAp is one of the most biocompatible material and addition of carbonate ions lead to increase in fracture toughness highly required in biomedical applications. The structural properties and its purity as single phase is confirmed by X-ray diffraction. Lattice imperfections and structural defects is investigated using XRD pattern model simulation, i.e. Rietveld's analysis. The substitution of CO32− in HAp structure leads to a decrease in crystallinity which ultimately lessens crystallite size of sample as verified by XRD analysis. FE-SEM micrographs confirms the formation of nanorods with cuboidal morphology and porous structure of HAp and CHAp samples. The particle size distribution histogram validates the constant decrease in size due to carbonate addition. The mechanical testing of prepared samples revealed the increase in mechanical strength from 6.12 MPa to 11.52 MPa due to the addition of carbonate content, which leads to a rise in fracture toughness, a significant property of an implant material from 2.93 kN to 4.22 kN. The cumulative effect of CO32− substitution on HAp structure and mechanical properties has been generalized for the application as biomedical implant material or biomedical smart materials.

Citrate-Assisted One-Pot Hydrothermal Preparation of Carbonated Hydroxyapatite Microspheres

Carbonated hydroxyapatite (CHA) microspheres have aroused wide concern in biofields because of their excellent biological and surface properties. However, the facile preparation of CHA microspheres from organic compounds, especially the microstructural transformation during synthesis, has been rarely reported. In this work, CHA microspheres with an average diameter of 2.528 μm and a BET surface area of 51.0658 m2/g were synthesized via a one-pot hydrothermal method at 180 °C for 10 h by using calcium chloride, diammonium hydrogen phosphate, urea, and trisodium citrate (TSC) with a molar ratio of TSC to Ca of 1:2. The effects of hydrothermal treatment temperature and molar ratio of TSC to Ca on the morphology of the products were investigated. As a chelating agent, TSC is crucial to the formation of CHA microspheres during the hydrothermal homogeneous precipitation process. A possible mechanism of the microstructural transformation from bundle to dumbbell, dumbbell ball, and finally, microspheres regulated by TSC and urea was proposed. The CHA microspheres can be used as effective drug carriers for biomedical applications.

Enhanced effect of a novel bioactive glass-ceramic for dental application.

Dental caries is the most common chronic disease in humans, caused by the acid produced by the microflora in the mouth that dissolves the enamel minerals. Bioactive glass (BAG) has been used in various clinical applications due to its unique bioactive properties, such as bone graft substitutes and dental restorative composites. In this study, we introduce a novel bioactive glass-ceramic (NBGC) prepared through a sol-gel process under a water-free condition. The anti-demineralization and remineralization effects of NBGC were evaluated by comparing the measurements of bovine enamel surface morphology, surface roughness, surface micro-hardness, enamel elements, and mineral content before and after related treatments with a commercial BAG. The antibacterial effect was characterized by minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Results showed that NBGC had greater acid resistance and remineralization potential compared to commercial BAG. The fast formation of a hydroxy carbonate apatite (HCA) layer suggests efficient bioactivity. In addition to its antibacterial properties, NBGC shows promise as an ingredient in oral care products that can prevent demineralization and restore enamel.

Biomimetic Action of Zinc Hydroxyapatite on Remineralization of Enamel and Dentin: A Review

A literature search (Pubmed/MEDLINE and Scopus) of articles from 2003 to 2023 was conducted to analyze studies focused on the use of zinc-hydroxyapatite products. Duplicates were eliminated from the 5065 articles found, leaving 2076 articles. Of these, 30 articles were analyzed based on the use of products with zinc-carbonate hydroxyapatite in these studies. 30 articles were included. Most of the studies showed benefits in terms of remineralization and prevention of enamel demineralization in terms of occlusion of the dentinal tubules and reduction of dentinal hypersensitivity. Oral care products such as toothpaste and mouthwash with biomimetic zinc-carbonate hydroxyapatite were shown to provide benefits according to the aims of this review.

Synthesis of carbonate hydroxyapatite contained magnesium cations by dry mechano-milling

The B-type carbonate hydroxyapatite (CHA) containing Mg cations was synthesized through the dry mechano-milling between Indonesian limestone-based hydroxyapatite (HA) and magnesium carbonate (MgCO3). The novelty in this research is the selection of MgCO3 as a precursor that will donate CO32− and Mg2+ to the HA structure to form CHA-containing Mg cations. The crystalline phases and chemical structure of synthesized CHA were studied by X-ray diffraction, X-ray fluorescence, scanning electron microscope, and a particle size analyzer. The feasibility of this work is to be able to produce B-type CHA containing Mg cations that have the potential to be developed for biomaterial application.

A new type of carbonate hydroxyapatite nanoparticles made from PMMA and oyster shells: evaluation of structure, morphology and biocompatible properties

A new type of carbonate hydroxyapatite nanoparticles made from PMMA and oyster shells: evaluation of structure, morphology and biocompatible properties

Improvement of bioactivity with dual bioceramic incorporation to nanofibrous PCL scaffolds

Bone tissue injuries, diseases or related clinical interventions require bone tissue engineering (BTE) approaches for regeneration of large bone defects, especially for compromised situations. Most BTE applications in literature focused on composites of polymers with a single type of bioceramic. However, native bone matrix has various inorganic components. Accordingly, this study aimed to investigate the use of dual bioceramics in BTE scaffolds prepared by wet-electrospinning of Poly-caprolactone (PCL) and bioceramics; hydroxyapatite (HA), carbonated hydroxyapatite (CHA) and akermanite (AKR). After physicochemical characterizations of single and dual bioceramic-discs, it was found that AKR component should be at most 10% and thus, fibrous 3D composite scaffolds (PCL/HA; PCL/CHA; PCL/90HA/10AKR; PCL/90CHA/10AKR) were prepared. Scaffolds were then compared for degradation, swelling and microstructure properties. PCL/CHA, PCL/HA/AKR and PCL/CHA/AKR scaffolds improved apatite formation and presence of CHA, AKR or both in scaffolds increased Ca/P precipitation compared to HA involving scaffolds. Specifically, when two bioceramics were introduced, there was a noticeable increase in mineralization. No significant weight change was detected for scaffolds after two weeks of incubation. Presence of bioceramics in scaffolds significantly reduced swelling of PCL scaffolds with PCL/90HA10AKR and PCL/90CHA10AKR having higher swelling results than PCL/HA and PCL/CHA, respectively. Additionally, scaffolds with dual bioceramics (90HA10AKR, 90CHA10AKR) had higher cell proliferation for bone cells (Saos-2). In terms of osteogenic activity all groups showed increased ALP activity at 14 days compared to 7 days with PCL/CHA scaffolds having the highest value. Results suggests that newly developed PCL/90HA10AKR and PCL/90CHA10AKR composites hold potential for bone tissue engineering applications.

Diseño y comparativa de biomateriales para el tratamiento de defectos óseos. Estudio de su comportamiento in vivo en modelo animal de conejo

AimCompare bone formation capacity in vivo of two types of biomaterials designed as bone substitutes with respect to iliac crest autograft, one based on carbonate hydroxyapatites and the other one on bioactive mesoporous glass. Materials and methodsExperimental study consisting on 14 adult female New Zeland rabbits where a critical defect was made in the rabbit radius bone. The sample was divided into four groups: defect without material, with iliac crest autograft, with carbonatehydroxyapatite support, and with bioactive mesoporous glass support. Serial X-ray studies were carried out at 2, 4, 6 and 12 weeks and a microCT study at euthanasia at 6 and 12 weeks. ResultsIn the X-ray study, autograft group showed the highest bone formation scores. Both groups of biomaterials presented bone formation similar and greater than the defect without material, but always less than in the autograft group. The results of the microCT study showed the largest bone volume in the study area in the autograft group. The groups with bone substitutes presented greater bone volume than the group without material but always less than in the autograft group. ConclusionBoth supports seem to promote bone formation but are not capable of reproducing the characteristics of autograft. Due to their different macroscopic characteristics, each one could be suitable for a different type of defect.