Bone Graft Material Research Articles

Osteogenic potential of silver nanoparticles in critical sized mandibular bone defects: an experimental study in white albino rats.

Natural bone is a self-regenerating nanocomposite made of proteins and minerals. Such self-regenerative capacity can be negatively affected by certain diseases involving the bone or its surrounding tissues. Our study assesses the ability of bone grafting material to regenerate bone in animals who have artificially created critical-sized defects. Nanohydroxyapatite (HANPs) and silver nanoparticles (AgNPs) were synthesized and underwent characterization by transmission electron microscopy. The cytotoxic effect of the nanomaterials was evaluated by MTT assay using bone marrow mesenchymal stem cells (BMMSCs). Five mm critical size defects in white albino rats were utilized to assess the material's biocompatibility, and regenerative capacity. Histological and immunohistochemical analyses using collagen-I and tumor necrotic factor-alpha were also performed. Clinically, the tested materials did not cause any pathological changes. MTT results suggested that both materials showed high biocompatibility. Gel form of AgNPs achieved bone regenerative potential and anti-inflammatory effect being significantly higher than what was seen in HANPs after 21days post-surgically. The utilization of AgNPs to improve anti-inflammatory and osteoregenerative activities was the primary research outcome of this study. AgNPs have the potential to be useful biomaterial in accelerating bone healing process.

Novel Foamed Magnesium Phosphate Antimicrobial Bone Cement for Bone Augmentation.

In dental implant surgery, infection is identified as the primary factor contributing to the failure of bone grafts. There is an urgent need to develop bone graft materials possessing antibacterial characteristics to facilitate bone regeneration. Magnesium phosphate bone cement (MPC) is highly desirable for bone regeneration due to its favorable biocompatibility, plasticity, and osteogenic capabilities. However, the limited porosity of conventional MPC hinders the nutrient supply, gas diffusion, and cell infiltration, thereby compromising its osteogenic efficacy. This research focused on the fabrication of a highly porous MPC (CaCO3/CA-MPC) by incorporating citric acid (CA) and calcium carbonate (CaCO3) as foaming agents. The resulting material demonstrated enhanced physicochemical properties, bioactivity, and antimicrobial effects. When compared with conventional MPC, human periodontal ligament stem cells (hPDLSCs) showed improved osteogenic differentiation when cultured with CaCO3/CA-MPC. The inclusion of foaming agents significantly enhanced the antimicrobial efficacy of MPC against both Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli). The results of invivo anti-infection experiments in rats revealed that 3%CaCO3/CA-MPC displayed superior bactericidal activity compared with Bio-Oss and control groups (p < 0.05), thereby enhancing the anti-infective outcomes post-bone grafting and stimulating osteogenesis in the infected bone defect region. The study demonstrated that MPC containing 3%CaCO3/CA exhibited excellent antimicrobial and osteogenic properties both invitro and invivo, suggesting its potential as a promising candidate as bone graft material for dental implant surgeries.

In Vitro Osteogenic Response to Copper-Doped Eggshell-Derived Hyroxyapatite With Macrophage Supplements.

The high bioactivity and biocompatibility of hydroxyapatite (HAP) make it a useful bone graft material for bone tissue engineering. However, the development superior osteoconductive and osteoinductive materials for bone regeneration remains a challenge. To overcome these constraints, Cu-doped hydroxyapatite (HAP(Cu)) from waste eggshells has been produced for bone tissue engineering. The materials produced were characterized using Fourier transform infrared spectroscopy, x-ray diffraction, and photoelectron spectroscopy. The scanning microscopy images revealed that the developed HAP was a rod-like crystalline structure with a typical 80-150 nm diameter. Energy-dispersive x-ray spectroscopy showed that the generated HAP was mostly composed of calcium, oxygen, and phosphorus. The Ca/P molar ratios in eggshell-derived and copper-doped HAP were 1.61 and 1.67, respectively, similar to the commercially available HAP ratio (1.67). The WST-8 assay was used to assess the biocompatibility of HAPs with hBMSCs. HAP(Cu) in the media significantly altered the cytotoxicity of biocompatible HAP(Cu). The osteogenic potential of HAP(Cu) was demonstrated by greater mineralization than that of pure HAP or the control. HAP(Cu) showed higher osteogenic gene expression than pure HAP and the control, indicating its stronger osteogenic potential. Furthermore, we assessed the effects of sample-treated macrophage-derived conditioned medium (CM) on hBMSCs' osteogenesis. CM-treated HAP(Cu) demonstrated a significantly higher osteogenic potential vis-à-vis pure HAP(Cu). These findings revealed that HAP(Cu) with CM significantly improved osteogenesis in hBMSCs and can be explored as a bone graft in bone tissue engineering.

CRANIOPLASTY: AUTOLOGOUS BONE GRAFT VS TITANIUM MESH

Background: Cranioplasty (CP) is a neurosurgical procedure performed after decompressive craniectomy using autologous bone graft or various artificial materials. Objective: To determine differences in complications between patients who underwent CP using an autologous bone flap versus titanium mesh and to identify significant risk factors for post-CP complications. Study Design: Comparative cross-sectional study. Methods: A total of 38 patients, 29 males (76.4%) and 9 females (23.6%), were included in this study. All patients underwent cranioplasty with titanium mesh or autologous bone graft. Results: The results were compared between autografts and titanium implants. Autologous bone graft was used in 76.3% of the patients and titanium implant was used in 23.7%. Different complications occurred in 5.26% of the patients in both groups, 2.63% in the autologous group and 2.63% in the titanium mesh group respectively. Infection occurred in the surgical site in 5.26% of the patients in both groups (similar). Cranioplasty infection occurred in 2.63% of the patients who underwent autologous transplantation. One patient developed a hematoma in both groups. One patient underwent autologous bone graft removal, and one patient underwent mesh removal. Practical Implication: Titanium mesh cranioplasty is an essential procedure for junior neurosurgeons to learn and achieve good results, shorten hospital stay, and save hospital resources. Conclusion: Titanium mesh cranioplasty has similar complications to autologous bone cranioplasty.

Exploring the Biological Impact of β-TCP Surface Polarization on Osteoblast and Osteoclast Activity.

β-tricalcium phosphate (β-TCP) is a widely utilized resorbable bone graft material, whose surface charge can be modified by electrical polarization. However, the specific effects of such a charge modification on osteoblast and osteoclast functions remain insufficiently studied. In this work, electrically polarized β-TCP with a high surface charge density was synthesized and evaluated in vitro in terms of its physicochemical properties and biological activity. Polarization was performed to achieve a high surface charge density, which was quantified using a thermally stimulated depolarization current. The proliferation and differentiation of MC3T3-E1 osteoblast-like cells were assessed via WST-8 and alkaline phosphatase assays. Tartrate-resistant acid phosphatase (TRAP) activity and a resorption pit assay were used to evaluate the impact of surface charge on RAW264.7 osteoclast-like cell activity. Polarized β-TCP exhibited a surface charge of 1.3 mC cm-2. Electrically polarized surfaces significantly enhanced osteoblast proliferation and differentiation. TRAP activity assays demonstrated effective osteoclast differentiation of RAW264.7 cells, with enhanced activity observed on charged surfaces. Resorption pit assays further revealed improved osteoclast resorption capacity on β-TCP surfaces with a polarized charge. These findings indicate that β-TCP with a highly dense surface charge promotes osteoblast proliferation and differentiation, as well as osteoclast activity and resorption capacity.

CHANGES IN THE OPTICAL DENSITY OF BONE TISSUE IN DENTAL IMPLANT PLACEMENT

Introduction. The success of dental implant placement depends primarily on the initial stability of the implant and the bone density, which allows achieving the necessary osseointegration for effective treatment. Optimal stability of dental implants depends on the quality and quantity of bone tissue, therefore bone density plays a key role in determining the prognosis of dental implantation, since the survival of implants is strongly correlated with the amount of bone tissue, and bone density is a crucial parameter for assessing the amount of bone tissue. Therefore, lower levels of cancellous bone density and less bone tissue are more likely to lead to dental implant loss. This study aims to evaluate the effectiveness of using a soft tissue cuff reinforced with bone grafting material (BGM) by the follow-up changes in the optical density of bone tissue on the implant side after one-stage dental implant placement. Materials and methods. At the start of the study, two patient groups were formed: the main group, comprising 25 individuals who received BGM (bone grafting material), and the control group, consisting of 26 individuals who did not receive BGM. Optical bone density was assessed prior to implantation, at 3 months, and one year post-implantation using cone beam computed tomography, evaluated according to the C. E. Misch and L. T. Kircos classification. The obtained results were processed using the “Statistica 13” software (Copyright 1984–2018 TIBCO Software Inc. All rights reserved. License No. JPZ8041382130ARCN10-J). Results. The optical density of bone tissue in the area of one-stage dental implantation significantly decreased from the central teeth to the posterior region. In both groups before implantation, it was significantly highest relative to all teeth in the area of central incisors, and significantly lowest relative to almost all teeth in the area of the second premolar and first molar. In the main group had been used, the optical density of bone tissue in the area of one-stage dental implantation in the upper jaw was significantly higher than in the lower jaw. In the control group had been used, no significant difference between the indicators of optical density of bone tissue depending on the jaw was found. In the main group in dental implantation provided a significant increase in the optical density of bone tissue in 3 months by 118.7 HU, and in a year by 175.6 HU; a significant increase in the optical density of bone tissue in a year in the LI area by 233 HU, 2PM area by 503.2 HU and 1M area by 244 HU (in the control group, a significant increase in the optical density of bone tissue was not achieved both in 3 months and a year after implantation) a year after implantation. There was a significant increase in the percentage of D1 and D2 bone types (42.9 % and 45.7 %, respectively), which is significantly higher than D3 type (11.4 %; χ2 = 10.08; p &lt; 0.002 and χ2 = 8.74; p &lt; 0.004, respectively), which indicated successful osseointegration of implants into bone tissue. Conclusions. Adequate optical bone density and the formation of D1/D2 bone tissue types, achieved through the development of a soft tissue cuff reinforced with bone graft material, contribute to improving the efficiency of dental implantation.

Enhancing bone graft efficacy: Antibacterial and osteogenic effects of cerium‐doped biphasic calcium phosphate scaffolds

AbstractBiphasic calcium phosphate powders, composed of hydroxyapatite and β‐tricalcium phosphate, have gained significant interest as excellent substitutes because of their similarity to natural bone mineral and biocompatibility. The objective was to enhance the biological efficacy of biphasic calcium phosphate powder‐based bone graft materials by incorporating trace elements, such as cerium, into the material. In the context of this investigation, a simple wet chemical precipitation technique was established for the purpose of fabricating microporous biphasic calcium phosphate powders scaffolds of cerium followed by gel casting. The 10% Ce in biphasic calcium phosphate powders scaffolds displayed a network of linked microporous structures characterized by consistent micropore size having 250 ± 25 swelling value. There were no observable alterations in the phase composition and microstructure of the scaffolds when cerium was doped. Further, Staphylococcus aureus was used in the polarization‐induced in vitro antibacterial investigation while the survival of bacteria was greatly reduced on polarized surfaces. The biological activity studies revealed that the 10% cerium‐doped biphasic calcium phosphate powders scaffold exhibited superior efficacy in promoting osteogenic differentiation and antibacterial activities compared to its counterpart. Additionally, polarization improves the antibacterial capabilities of these synthetic scaffolds. The stored charge was found to be 4.02 µC.cm−2 at 550°C.

Automated Segmentation of Graft Material in 1-Stage Sinus Lift Based on Artificial Intelligence: A Retrospective Study.

Accurate assessment of postoperative bone graft material changes after the 1-stage sinus lift is crucial for evaluating long-term implant survival. However, traditional manual labeling and segmentation of cone-beam computed tomography (CBCT) images are often inaccurate and inefficient. This study aims to utilize artificial intelligence for automated segmentation of graft material in 1-stage sinus lift procedures to enhance accuracy and efficiency. Swin-UPerNet along with mainstream medical segmentation models, such as FCN, U-Net, DeepLabV3, SegFormer, and UPerNet, were trained using a dataset of 120 CBCT scans. The models were tested on 30 CBCT scans to evaluate model performance based on metrics including the 95% Hausdorff distance, Intersection over Union (IoU), and Dice similarity coefficient. Additionally, processing times were also compared between automated segmentation and manual methods. Swin-UPerNet outperformed other models in accuracy, achieving an accuracy rate of 0.84 and mean precision and IoU values of 0.8574 and 0.7373, respectively (p < 0.05). The time required for uploading and visualizing segmentation results with Swin-UPerNet significantly decreased to 19.28 s from the average manual segmentation times of 1390 s (p < 0.001). Swin-UPerNet exhibited high accuracy and efficiency in identifying and segmenting the three-dimensional volume of bone graft material, indicating significant potential for evaluating the stability of bone graft material.

Various materials which can be used as bone grafting materials in dentistry: A literature review

Various materials which can be used as bone grafting materials in dentistry: A literature review

Regulated Magnesium Ion Release From Polydopamine‐Mg Modified Polyetheretherketone Surface for Improved Anti‐Infection and Osseointegration Properties

ABSTRACTPolyetheretherketone (PEEK) emerges as a highly promising biopolymer due to its mechanical properties and elastic modulus akin to those of human cortical bone. Despite these advantages, the clinical utilization of PEEK is often hindered by its limited bioactivity and suboptimal capability for bone integration. Herein, we introduce a facile and expeditious method for enhancing the osseointegration efficacy of PEEK substrates by depositing polydopamine (PDA) chelated with magnesium ions at varying concentrations (0.02, 0.1, and 0.5 M) as a surface coating (PDA‐Mg). This PDA‐Mg‐modified PEEK surface exhibits distinctive properties, including antibacterial properties (antibacterial rate of 93.267%), improved vascular regeneration, and osteogenic promotion (ALP activity increased by 239.5%). Moreover, the Mg2+ ions are released in a regulated way, and the impact of Mg2+ concentration on the aforementioned properties has been thoroughly examined. Our study demonstrates that PDA‐Mg‐modified PEEK offers a highly promising prospect for clinical applications. Specifically, these implants stand out as exceptional candidates for bone graft materials, with the potential to significantly improve patient outcomes and accelerate recovery processes.

Dynamics of soft tissue thickness in the area of one-stage dental implantation with the use of a soft tissue cuff reinforced with bone graft material

Aim. The study aims to compare the dynamics of the increase in the thickness of soft tissues in the area of one-stage dental implantation after the use of a xenogenic collagen matrix and a soft tissue cuff reinforced with bone graft material (BGM). Materials and methods. The study enrolled 51 patients who received one-stage dental implantation. Depending on the dental implantation technique, the patients were divided into two groups. The main group comprised 25 patients who after teeth extraction had their implants placed into a prepared socket preliminary filled with Sensobone xenograft, after which BGM was formed with the subsequent fixation of a temporary crown. The comparison group included 26 patients who after teeth extraction had their implants placed into a prepared socket preliminary filled with Sensobone xenograft, after which the soft tissue area was filled with Senobone xenograft, with the subsequent fixation of the temporary crown. The attached mucous membrane (AMM) thickness around the implant was measured before implantation and again after 3 months and one year (the distance from the top of the alveolar ridge center to the middle of the muco-gingival junction in the vestibular direction was measured with a periodontal probe). The results of the study were processed on a PC using the statistical package of the licensed software Statistica 13.0 (Copyright 1984–2018 TIBCO Software Inc. All rights reserved. License No. JPZ804I382130ARCN10-J). Results. The thickness of the AMM around the one-stage dental implantation area before implantation and in the dynamics did not depend on the jaw in both groups. Before implantation, the lowest values of the AMM thickness in patients of both groups were registered in the area of the canine and the first molar. The AMM thickness did not depend on the age and sex of the patients, as well as on the type of teeth and jaws. The use of BGM in one-stage dental implantation provided a significant increase in the AMM thickness by 1.38 mm in 3 months after implantation, and by 1.45 mm in a year (the intergroup difference was 0.29 mm in 3 months and 0.32 mm in a year), and a significant increase in the AMM thickness on both jaws, by 1.36 mm on the upper jaw and 1.41 mm on the lower jaw in 3 months and by 1.44 mm on the upper jaw and by 1.5 mm on the lower jaw in a year (the intergroup difference was 0.32 mm on the upper jaw and 0.33 mm on the lower jaw in a year) as well as a significant increase in the AMM thickness in all teeth after a year of follow-up. There were no dental implant failures in both groups, and the survival rate of implants was 100 % one year after the placement. Conclusions. The effectiveness of one-stage dental implantation is facilitated by the adequate AMM thickness provided by BGM.

Optimization of 3D-printed titanium interbody cage design. Part 2: An in vivo study of spinal fusion in sheep.

3D-printed titanium cage designs can incorporate complex, porous features for bone ingrowth and a greater surface area for minimizing subsidence. In a companion study (Part 1), we determined that increased surface area leads to decreased subsidence; however, it remains unclear how increasing the cage surface area, resulting in a smaller graft aperture, influences fusion. We evaluated the effects of surface area of 3D-printed titanium cages and the use of autologous bone grafts on spinal fusion in sheep. In vivo large animal study in 12 sheep. Interbody fusion was performed in 12 adult sheep at 24 levels (L2-3 and L4-5) using 3D-printed titanium cages with bilateral pedicle screw fixation. The cage designs varied in aperture: standard (low endplate surface area), small (medium endplate surface area), or none (high endplate surface area). These cages were packed with autologous iliac crest bone grafts (ICBG). A fourth group was implanted without bone grafts, using the no-aperture cage. Fusion was evaluated at 16 weeks via manual palpation, microcomputed tomography (microCT), histology, and histomorphometry. Standard, small, and no-aperture cages packed with ICBG resulted in high fusion rates (80%, 100%, and 83%, respectively) at 16 weeks by manual palpation, and these results were not significantly different. Implantation without ICBG was associated with a significantly lower fusion rate (33%, p<.05). Histological, histomorphometry, and microCT results supported the findings obtained by manual palpation; findings from these modalities showed new bone spanning the vertebral endplates in the spines graded as fused by manual palpation. Similar fusion results for standard, small, and no-aperture cage designs packed with ICBG suggest that aperture size does not influence fusion results in the sheep model. However, without ICBG grafting, fusion was significantly decreased, suggesting that graft material is necessary to predictably obtain fusion in this model. When the in vitro subsidence data (companion study, Part 1) is considered with the in vivo fusion data described here, porous 3D-printed titanium cages with maximal surface endplate contact and bone grafting perform favorably, resulting in low subsidence and high fusion rates. 3D-printed porous titanium interbody cages are novel devices with increasing clinical use. The study results show that the aperture size of the interbody cage did not influence fusion in a large animal (sheep) model. The use of bone graft material was the most important variable affecting fusion. These data suggest that the clinical use of 3D Ti cages without graft material should be avoided.

Mineralized collagen plywood contributes to bone autograft performance

Autologous bone (AB) is the gold standard for bone-replacement surgeries1, despite its limited availability and the need for an extra surgical site. Traditionally, competitive biomaterials for bone repair have focused on mimicking the mineral aspect of bone, as evidenced by the widespread clinical use of bioactive ceramics2. However, AB also exhibits hierarchical organic structures that might substantially affect bone regeneration. Here, using a range of cell-free biomimetic-collagen-based materials in murine and ovine bone-defect models, we demonstrate that a hierarchical hybrid microstructure—specifically, the twisted plywood pattern of collagen and its association with poorly crystallized bioapatite—favourably influences bone regeneration. Our study shows that the most structurally biomimetic material has the potential to stimulate bone growth, highlighting the pivotal role of physicochemical properties in supporting bone formation and offering promising prospects as a competitive bone-graft material.

Fibrinogen-Induced Regeneration Sealing Technique (F.I.R.S.T.): A Retrospective Clinical Study on 105 Implants with a 3-7-Year Follow-Up.

Background/Objectives: The primary aim of this retrospective clinical study was to assess the success and bone gain achieved by using the Fibrinogen-Induced Regeneration Sealing Technique (F.I.R.S.T.) in different indications. Methods: In this single-center retrospective clinical study, F.I.R.S.T. was performed in the following indications: alveolar ridge preservation (ARP), immediate implant placement, and horizontal and vertical guided bone regeneration (GBR) with simultaneous dental implant placement. F.I.R.S.T. is a modified approach to GBR characterized by the application of a porcine cortical lamina, as a long-term resorbable bone barrier to cover the bone defect, and a fibrin sealant for easy adaptation of the xenogenic bone graft material and the fixation of the collagenic bone barrier. Patients with uncontrolled systemic diseases, medications, or diseases that may alter bone metabolism; local inflammation; poor oral hygiene; and heavy smoking were excluded from this study. Horizontal and vertical bone gain (HBG and VBG) were measured by comparing postoperative and preoperative cone beam computed tomography (CBCT) reconstructions. Patients were recalled for controls and oral hygiene treatment every 6 months. Results: Altogether, 62 patients (27 male, 35 female, age 63.73 ± 12.95 years) were included in this study, and 105 implants were placed. Six implants failed during the 50.67 ± 22.18-month-long follow-up. Cumulative implant survival throughout the groups was 94.29 %. In the immediate implant group, HBG was 0.86 mm (range: -0.75-8.19 mm) at the 2 mm subcrestal level, while VBG was 0.87 ± 1.21 mm. In the ARP group, HBG was 0.51 mm (range: -0.29-3.90 mm) at the 2 mm subcrestal level, while VBG was -0.16 mm (range: -0.52-0.92 mm). In the horizontal GBR group, HBG was 2.91 mm (range: 1.24-8.10 mm) at the 2 mm subcrestal level. In the vertical GBR group, VBG was 4.15 mm (range: 3.00-10.41 mm). Conclusions: F.I.R.S.T. can be utilized successfully for bone augmentation. The vertical and horizontal bone gains achieved through F.I.R.S.T. allow for implant placement with adequate bone width on both the vestibular and oral aspects of the implant.

Optimizing α-tricalcium phosphate bone cement composite formulations: The critical role of bioactive glass particle size

Calcium phosphate cements (CPCs) have been extensively utilized as bone grafting material due to their inherent osteoconductive properties, although they often lacked sufficient biological performance for effective bone healing at the defect site. Incorporating mesoporous bioactive glass (MBG) into CPCs offers a solution by improving porosity, promoting degradation and increasing the available surface area. In the scope of this study, we integrated MBG into CPCs and assessed the impact of varying MBG particle sizes (<20 µm, <38 µm, <100 µm) on the setting characteristics, microstructure, mechanical strength, and preliminary cell response of CPCs. Investigations revealed that < 20 µm MBG particles significantly improved the setting characteristics and compressive strength of CPCs, while < 38 µm particles promoted degradation and ion release, facilitating apatite formation. MBG incorporation was found to promote microstructural homogeneity and facilitate apatite formation, with particle size directly affecting these outcomes. Biocompatibility assessments indicated no cytotoxic effects, supported by the favorable cellular responses (> 92 % viability compared to control group). These findings underscore the critical impact of MBG particle size on developing advanced CPCs for biomedical applications, guiding future design and optimization strategies.

ESR measurement of carbonated hydroxyapatite for dosemeter.

We have examined a dosimetry characteristic of carbonate hydroxyapatite (CO3HAp), which is a dental bone graft material. The purpose of this work is to investigate the reproducibility and stability of radiation-induced radicals on CO3HAp samples and assess the feasibility of using these materials as dosemeters. CO3HAp samples were exposed to gamma rays with dose range from 10 to 10000Gy. The electron spin resonance (ESR) spectra for irradiated samples were measured. Variation of peak-to-peak amplitude of the ESR signal intensity as a function of absorbed dose for CO3HAp was compared with that for alanine dosemeters, suggesting that the CO3HAp sample has a good linear dose response in the range from 10to 10000Gy as well as does the alanine dosemeters.

Osteoinduction and Osteoconduction Evaluation of Biodegradable Magnesium Alloy Scaffolds in Repairing Large Segmental Defects in Long Bones of Rabbit Models.

Magnesium (Mg) alloy scaffolds demonstrate promising potential for clinical applications in the repair of segmental bone defects. However, the specific mechanisms of osteoconduction and osteoinduction facilitated by these scaffolds themselves during the bone reconstruction process remain inadequately defined. This investigation systematically assesses the properties of MAO-coated Mg base implants both in vitro and in vivo. Furthermore, it elucidates the correlation between scaffold characteristics and bone regeneration in the repair of extensive long-bone defects, measuring up to 20 mm, without the use of additional bone graft materials. Electrochemical measurements and immersion tests conducted in vitro indicate that the MAO coating substantially enhances the corrosion resistance of the underlying Mg alloy. Meanwhile, the application of MAO coatings has been shown to significantly improve cytocompatibility, cellular adhesion, and osteogenic differentiation, as evidenced by the CCK-8 assays, ALP activity measurements, Western blot, and RT-qPCR in vitro. At 24 weeks postimplantation with the MAO-coated Mg alloy scaffold, the large segmental defects were effectively repaired concerning both integrity and continuity. The Micro-CT gradual replacement of old bone with new bone on the implant surface was observed by X-ray and Micro-CT. Meanwhile, the histological results indicated that the MAO-coated Mg alloy scaffold maintained a robust osteogenic response. In summary, the MAO-coated Mg alloy scaffold independently exhibits effective osteoconduction and osteoinduction, playing a significant role in bone repair function without the need for additional bone graft materials.

Optimizing Bone Regeneration with Demineralized Dentin-Derived Graft Material: Impact of Demineralization Duration in a Rabbit Calvaria Model.

This study evaluated the regenerative potential of demineralized dentin-derived matrix (DDM) as a bone graft material in rabbit calvaria. DDM, sourced from extracted teeth, is emerging as an alternative to traditional grafts like allografts and xenografts. We aimed to identify the most effective demineralization protocol to optimize the regenerative capacity of DDM. Four groups were compared: a control group without grafts, a non-demineralized DDM group, and two demineralized DDM groups (15 and 30 min demineralization). Histomorphometric analysis was conducted in a randomized and blinded setting at 2, 4, and 8 weeks post-graft placement. The results revealed that the 15 min demineralized DDM group showed the most significant new bone formation (42.51% ± 6.40% at 8 weeks; p < 0.05), suggesting its potential as a highly effective regenerative graft material.

Decellularized Extracellular Matrix Scaffolds: Recent Advances and Emerging Strategies in Bone Tissue Engineering.

Bone tissue engineering (BTE) is a complex biological process involving the repair of bone tissue with proper neuronal network and vasculature as well as bone surrounding soft tissue. Synthetic biomaterials used for BTE should be biocompatible, support bone tissue regeneration, and eventually be degraded in situ and replaced with the newly generated bone tissue. Recently, various forms of bone graft materials such as hydrogel, nanofiber scaffolds, and 3D printed composite scaffolds have been developed for BTE application. Decellularized extracellular matrix (DECM), a kind of natural biological material obtained from specific tissues and organs, has certain advantages over synthetic and exogenous biomaterial-derived bone grafts. Moreover, DECM can be developed from a wide range of biological sources and possesses strong molding abilities, natural 3D structures, and bioactive factors. Although DECM has shown robust osteogenic, proangiogenic, immunomodulatory, and bone defect healing potential, the rapid degradation and limited mechanical properties should be improved for bench-to-bed translation in BTE. This review summarizes the recent advances in DECM-based BTE and discusses emerging strategies of DECM-based BTE.

Vertical Alveolar Ridge Regeneration by Means of Periosteal Activation-A Proof-of-Principle Study.

To assess the possibility of vertical alveolar ridge augmentation by means of activation of the periosteum. Six adult male Beagle dogs were used for the study. All premolars and first molars were extracted, and one vertical saucer-shaped bony defect was created on each side of the mandible. After 3 months of healing, full-thickness muco-periosteal flaps were elevated, and one distraction device was placed on each side of the mandible. The distraction plate was left submerged, and the activation mechanism connected to the distraction rod was exposed intra-orally. The protocol of periosteal activation (PP: periosteal 'pumping') was initiated after a latency of 7 days. The alternation of activation and relaxation at the rate of 0.35 mm/12 h during 5 days was followed by the sole activation of 0.35 mm/12 h for 5 days (PP group). Devices were left inactivated on the contralateral control side of the mandible (C group). All animals were euthanized after 8 weeks of consolidation. Samples were analysed histologically and by means of micro-CT. New mature lamellar bone was formed over the pristine bone in all groups. More intensive signs of bone modelling and remodelling were observed in the PP group compared to the C group. Mean new bone, bone marrow, connective tissue and total volumetric densities were greater in the PP group (p < 0.001, p = 0.001, p = 0.003 and p < 0.001, respectively). No differences were observed in the relative area parameters. Total tissue volume and bone volume were higher in the PP group (p = 0.031 and p = 0.076, respectively), while the bone mineral densities were higher in the C group (p = 0.041 and p = 0.003, respectively). Trabecular number, trabecular thickness and trabecular separation values were similar between the two groups. Regeneration of vertical alveolar bone ridge defects may be enhanced by activation of the periosteum, without the application of bone grafting materials.