Precision pore structure optimization of additive manufacturing porous tantalum scaffolds for bone regeneration: A proof-of-concept study.

Currently, the treatment of bone defects in arthroplasty is a challenge in clinical practice. Nonetheless, commercially available orthopaedic scaffolds have shown limited therapeutic effects for large bone defects, especially for massiveand irregular defects. Additively manufactured porous tantalum, in particular, has emerged as a promising material for such scaffolds and is widely used in orthopaedics for its exceptional biocompatibility, osteoinduction, and mechanical properties. Porous tantalum has also exhibited unique advantages in personalised rapid manufacturing, which allows for the creation of customised scaffolds with complex geometric shapes for clinical applications at a low cost and high efficiency. However, studies on the effect of the pore structure of additively manufactured porous tantalum on bone regeneration have been rare. In this study, our group designed and fabricated a batch of precision porous tantalum scaffolds via laser powder bed fusion (LPBF) with pore sizes of 250 µm (Ta 250), 450 µm (Ta 450), 650 µm (Ta 650), and 850 µm (Ta 850). We then performed a series of in vitro experiments and observed that all four groups showed good biocompatibility. In particular, Ta 450 demonstrated the best osteogenic performance. Afterwards, our team used a rat bone defect model to determine the in vivo osteogenic effects. Based on micro-computed tomography and histology, we identified that Ta 450 exhibited the best bone ingrowth performance. Subsequently, sheep femur and hip defect models were used to further confirm the osteogenic effects of Ta 450 scaffolds. Finally, we verified the aforementioned in vitro and in vivo results via clinical application (seven patients waiting for revision total hip arthroplasty) of the Ta 450 scaffold. The clinical results confirmed that Ta 450 had satisfactory clinical outcomes up to the 12-month follow-up. In summary, our findings indicate that 450 µm is the suitable pore size for porous tantalum scaffolds. This study may provide a new therapeutic strategy for the treatment of massive, irreparable, and protracted bone defects in arthroplasty.

Application of the Modified RUST Score in Tibial Bone Transport and Factors Associated with Docking Site Complications.

Aim: Reconstruction of segmental bone defects with bone transport is a well-established treatment. Mechanical complications at the docking site after frame removal are common. These complications include malunion, non-union, axial deviation and refracture. A simple tool to assess the healing of the docking site is currently lacking. The aim of this study is to evaluate the use of the modified RUST (mRUST) score in the setting of bone transport and to identify factors associated with an increased risk of docking site complications. Methods: This retrospective study was conducted at a single tertiary centre in South Africa, included 24 patients with a tibial bone defect treated with bone transport and a circular frame between 2014 and 2023. Demographic data, clinical and bone transport characteristics were recorded. Mechanical complications, such as fracture, non-union, any angulation >5°, shortening >5 mm, or any other complication requiring reoperation, were recorded. The mRUST was adapted as a ratio for the purpose of this study to overcome the common occurrence of cortices being obscured by the frame. The mRUST ratio was applied before and after frame removal for each patient by three appraisers. Comparison between the groups with and without complications was performed regarding bone transport characteristics, docking site configuration and mRUST ratio. The correlation of the score between radiographs before and after frame removal was assessed. The inter-rater reliability of the mRUST was analysed using Fleiss Kappa statistics for each cortex individually and the intraclass correlation coefficient (ICC) for the mRUST ratio. Results: In this study, 20 men and 4 women with a median age of 26 years were included. The overall rate of mechanical complications after frame removal was 21.7%. Complications were all related to the docking site, with two angulations, two fractures and one non-union. Demographics, bone transport characteristics and mRUST ratio before and after frame removal were similar between the two groups. Regarding the configuration of the docking site, an angle of 45° or more between the bone surfaces was associated with the occurrence of mechanical complications (p < 0.001). The correlation of the mean mRUST ratio before and after frame removal showed a moderate relationship, with a Spearman correlation coefficient of 0.50 (p-value 0.13). The inter-rater reliability of the mRUST was "fair" (kappa 0.21-0.40) for the scoring of individual cortices, except for one score which was "slight" (kappa 0.00-0.20). The ICC of the mRUST ratio was 0.662 on radiographs with the frame, and 0.759 after frame removal. Conclusion: This study did not find the mRUST or mRUST ratio useful in assessing the healing of the docking site to decide on the best time to remove the frame. However, a notable finding was that the shape and orientation of the bone ends meeting at the docking site might well be relevant to decrease complication rates. If the angle between the bony surfaces is 45° or more, it may be associated with an increased risk of complications. It may be worthwhile considering reshaping these bone ends at the time of debridement or formal docking procedure to be more collinear, in order to reduce the potential for mechanical complications such as non-union, axial deviation or refracture at the docking site. How to cite this article: Kummer A, Nieuwoudt L, Marais LC. Application of the Modified RUST Score in Tibial Bone Transport and Factors Associated with Docking Site Complications. Strategies Trauma Limb Reconstr 2024;19(2):73-81.

Impact of Freeze-dried Corticocancellous Bone Allograft Combined with Enamel Matrix Derivative in the Treatment of Critical-sized Calvarial Bone Defects: An Animal Study.

AIM: This study compared the quality and quantity of newly formed bone in rabbits' critical-sized calvarial defects filled with enamel matrix derivative (EMD) combined with freeze-dried bone allograft (FDBA) vs FDBA alone. MATERIALS AND METHODS: A total of 24 adult male white New Zealand rabbits were included. In each rabbit, three bone defects with a diameter of 8 mm were created on the calvarium bone; the first defect was left untreated, while the second was filled with FDBA, and the third was filled with EMD + FDBA. Twelve rabbits were randomly euthanized after a month, and the remaining 2 month postsurgery. Bone sections were histologically evaluated by hematoxylin and eosin and vascular endothelial growth factor (VEGF), alkaline phosphatase (ALP), osteoprotegerin (OPG), and receptor activator of NF-kappaB (RANK) immune-histochemical staining. RESULTS: An improvement in the newly formed bone percentage was found in the defects filled with EMD + FDBA in comparison with FDBA and control defects at 1 month and 2 months postsurgery. Additionally, the expression of VEGF, ALP, OPG, and RANK showed highly significant differences in the defects filled with EMD + FDBA compared to the FDBA and control ones at 1 month postsurgery (p = 0.001). Meanwhile, VEGF and ALP expression showed a significant decrease in defects filled with EMD + FDBA compared to the FDBA and control ones (p = 0.001), while OPG and RANK expression showed non-significant differences between treated groups at 2 months postsurgery. CONCLUSION: Enamel matrix derivative combined with FDBA has a synergistic effect on bone formation and graft substitution. This combination accelerates the expression of VEGF, ALP, OPG, and RANK. CLINICAL SIGNIFICANCE: The combination of EMD and FDBA accelerates and ameliorates the quality of newly formed bone, aiding in maxillofacial reconstruction. How to cite this article: Zakri RN, Grawish ME, Mowafey B, et al. Impact of Freeze-dried Corticocancellous Bone Allograft Combined with Enamel Matrix Derivative in the Treatment of Critical-sized Calvarial Bone Defects: An Animal Study. J Contemp Dent Pract 2024;25(5):424-431.

Immediate implant placement in damaged extraction sockets: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVES: The aim of this study was to observe whether immediate implant placement (IIP) into damaged extraction sockets is a successful modality for treating hopeless teeth that require extraction. DATA SOURCE: An electronic search was carried out through four databases (PubMed/MEDLINE, Web of Science, Scopus, and ScienceDirect) to identify randomized controlled trials (2013-2023) to understand whether IIP in damaged sockets is a successful treatment. The focus question was, 'In a patient with a hopeless tooth that needs extraction with the indication for dental implant treatment, is IIP in damaged extraction sockets, compared to undamaged sockets or healed sites, an effective method for the replacement of hopeless teeth and achieving a favorable clinical result?' The risk of bias was appraised and a meta-analysis using random effect was applied. Five studies with 135 patients and 138 implants were included. The implant survival rate was 100% for all studies and period evaluated; the pink esthetic score (PES) scores had no statistically significant result for all articles that evaluated this parameter; the soft tissue changes was reported by two studies: one found no significant differences and the other showed that the test group experienced reduced soft tissue loss at the 1-year evaluation (measured with digital intraoral scanners); other two studies assessed the marginal bone loss, presenting no differences between groups. The meta-analysis showed homogeneity between the studies. There was an equilibrium among the groups in the various studies included, and age tended to be lower in the test group. The buccal bone tissue and pink esthetic score showed favoritism for the test group but without statistical significance. CONCLUSION: This study suggests that IIP in the presence of buccal bone defects can achieve comparable clinical and radiological outcomes to traditional methods in the short term of the limited studies available. The buccal aspect is not possible to be evaluated through radiographs. Bone regeneration was essential to reach optimal results. It is important to emphasize that IIP requires adherence to rigorous criteria to ensure functionally acceptable results.

A Case of Simultaneous Sinus Augmentation and Oroantral Fistula Closure for Implant Preparation.

An oroantral communication (OAC) may form in the upper molar region after tooth extraction. The patient is a 59-year-old female, who is a non-smoker. At the initial visit, teeth #14, #15, and #17 were missing. After tooth #16 was extracted due to apical periodontitis, a bone defect with a diameter of approximately 4 mm was observed, leading to the formation of an oroantral fistula (OAF). Another window was created in the lateral wall adjacent to the superior part of the bone defect at the fistula site to achieve closure of the OAF through bone formation and simultaneously perform sinus floor elevation (lateral approach) for implant placement. Through this lateral window, instruments were inserted into the maxillary sinus towards the bone defect at the fistula site. During this process, the remaining bone between the lateral window and the bone defect at the fistula site was carefully removed with instruments, connecting the two bone defects to facilitate the manipulation of the instruments. The Schneiderian membrane was elevated without enlarging the tear. Six months after these surgeries, a CBCT scan confirmed the closure of the fistula with hard tissue and the elevation of the sinus floor. Subsequently, three implants were placed, and prosthetic treatment was completed. Follow-up data is provided, including periapical X-ray and CBCT images taken two years and three months after surgery (one year and three months after the placement of the final prosthetic structure). The progress so far has been favorable.

The Treatment of Very Large Traumatic Bone Defects of the Tibia With a Polycaprolactone-Tricalcium Phosphate 3D-Printed Cage: A Review of Three Cases.

The need for an artificial scaffold in very large bone defects is clear, not only to limit the risk of graft harvesting but also to improve clinical success. The use of custom osteoconductive scaffolds made from biodegradable polyester and ceramics can be a valuable patient-friendly option, especially in case of a concomitant infection. Multiple types of scaffolds for the Masquelet procedure (MP) are available. However, these frequently demonstrate central graft involution when defects exceed a certain size and the complication rates remain high. This paper describes three infected tibial defect nonunions with a segmental defect over 10 centimeters long treated with a three-dimensional (3D)-printed polycaprolactone-tricalcium phosphate (PCL-TCP) cage in combination with biological adjuncts. Three male patients, between the ages of 37 and 47, were treated for an infected tibial defect nonunion after sustaining Gustilo grade 3 open fractures. All had a segmental midshaft bone defect of more than 10 centimeters (range 11-15cm). First-stage MPs consisted of extensive debridement, external fixation, and placement of anterior lateral thigh flaps. Positive cultures were obtained from all patients during this first stage, which were treated with specific systemic antibiotics for 12 weeks. The second-stage MP was carried out at least two months after the first stage. CT scans were obtained after the first stage to manufacture defect-specific cages. In the final procedure, a custom 3D-printed PCL-TCP cage (Osteopore, Singapore) was placed in the defect in combination with biological adjuncts (BMAC, RIA-derived autograft, iFactor, and BioActive Glass). Bridging of the defect, assessed at six months by CT, was achieved in all cases. SPECT scans six months post-operatively demonstrated active bone regeneration, also involving the central part of the scaffold. All three patients regained function and reported less pain with full weight bearing. This case report shows that 3D-printed PCL-TCP cages in combination with biological adjuncts are a novel addition to the surgical treatment of very large bone defects in (infected) post-traumatic nonunion of the tibia. This combination could overcome some of the current drawbacks in this challenging indication.

The Biocompatibility and the Effect of Titanium and PEKK on the Osseointegration of Customized Facial Implants.

The purpose of this study was to investigate the optimization of computer-aided design/computer-aided manufacturing (CAD/CAM) patient-specific implants for mandibular facial bone defects and compare the biocompatibility and osseointegration of machined titanium (Ma), Sandblasted/Large-grit/Acid-etched (SLA) titanium, and polyetherketoneketone (PEKK) facial implants. We hypothesized that the facial implants made of SLA titanium had superior osseointegration when applied to the gonial angle defect and prevented the senile atrophy of the bone. Histologic findings of the soft-tissue reaction, hard-tissue reaction, and bone-implant contact (BIC (%) of 24 Ma, SLA, and PEKK facial implants at 8 and 12 weeks were investigated. There was no statistical difference in the soft tissue reaction. Bone was formed below the periosteum in all facial implants at 12 weeks and the BIC values were significantly different at both 8 and 12 weeks (p < 0.05). Ma, SLA, and PEKK facial implants are biocompatible with osseointegration properties. SLA can enhance osseointegration and provoke minimal soft tissue reactions, making them the most suitable choice. They provide an excellent environment for bone regeneration and, over the long term, may prevent atrophy caused by an aging mandible. The bone formation between the lateral surface of the facial implant and periosteum may assist in osseointegration and stabilization.

Biomechanical validation of a tibial critical-size defect model in minipigs.

BACKGROUND: Autologous cancellous bone grafting still represents the gold standard for the therapy of non-healing bone defects. However, donor site morbidity and the restricted availability of autologous bone grafts have initiated scientists to look for promising alternatives to heal even large defects. The present study aimed to evaluate the biomechanical potential and failure properties of a previously developed metaphyseal critical-size defect model of the proximal tibia in minipigs for future comparisons of bone substitute materials. METHODS: Fresh-frozen minipig tibiae were divided into two groups, with half undergoing the creation of critical-size defects. Specimens were subjected to biomechanical fatigue tests and load-to-failure tests. CT scans post-test verified bone damage. Statistical analysis compared the properties of defected and intact specimens. FINDINGS: In this model, it was demonstrated that under uniaxial cyclic compression within the loading axis, the intact tibiae specimens (8708 ± 202 N) provided a significant (p = 0.014) higher compressive force to failure than the tibiae with the defect (6566 ± 1653 N). INTERPRETATION: Thus, the used minipig model is suitable for comparing bone substitute materials regarding their biomechanical forces and bone regeneration capacity.

Metabolically activated energetic materials mediate cellular anabolism for bone regeneration.

The understanding of cellular energy metabolism activation by engineered scaffolds remains limited, posing challenges for therapeutic applications in tissue regeneration. This study presents biosynthesized poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] and its major degradation product, 3-hydroxybutyrate (3HB), as endogenous bioenergetic fuels that augment cellular anabolism, thereby facilitating the progression of human bone marrow-derived mesenchymal stem cells (hBMSCs) towards osteoblastogenesis. Our research demonstrated that 3HB markedly boosts in vitro ATP production, elevating mitochondrial membrane potential and capillary-like tube formation. Additionally, it raises citrate levels in the tricarboxylic acid (TCA) cycle, facilitating the synthesis of citrate-containing apatite during hBMSCs osteogenesis. Furthermore, 3HB administration significantly increased bone mass in rats with osteoporosis induced by ovariectomy. The findings also showed that P(3HB-co-4HB) scaffold substantially enhances long-term vascularized bone regeneration in rat cranial defect models. These findings reveal a previously unknown role of 3HB in promoting osteogenesis of hBMSCs and highlight the metabolic activation of P(3HB-co-4HB) scaffold for bone regeneration.

Controlling the pore size of carbonate apatite honeycomb scaffolds enhances orientation and strength of regenerated bone.

To restore functions of long bones and avoid reconstruction failure, segmental defects should be quickly repaired using abundant amounts of regenerated bone with high mechanical strength and orientation along the bone axis. Although both bone volume and bone matrix orientation are important for faster restoration of long bones with segmental defects, researchers have primarily focused on the former. Artificial bone scaffolds with uniaxial channels, (e.g., honeycomb (HC) scaffolds), are considered adequate for regenerating bone oriented along the bone axis. The channel size may affect the orientation, amount, and strength of the regenerated bone. In this study, we investigated the effects of channel size in carbonate apatite HC scaffolds on the orientation of bones regenerated in segmental bone defects and determined the adequate channel size. Carbonate apatite HC scaffolds, with different channel sizes (350, 550, 730, and 890 µm in length on the side of the square aperture), were fabricated by extrusion molding of a mixture of calcium carbonate and organic binder, debinding, and subsequent phosphatization to convert the composition from calcium carbonate to carbonate apatite. No significant difference in the amounts of regenerated bones was observed for different channel sizes. However, bone along the bone axis was formed in the channels ≤550 µm in size but not in channels ≥730 µm. The HC scaffolds with a channel size of 350 µm regenerated bone with higher bending strength than those with a channel size of 890 µm. However, bone regenerated with the HC scaffolds having channel sizes of 350, 550, and 730 µm showed equal bending strength. Thus, the adequate channel size for fast regeneration of high-strength bone, oriented to the bone axis, is ≤730 µm. To the best of our knowledge, this is the first study to report the effect of channel size on bone orientation and strength. The findings of this study are relevant to the fast repair of segmental bone defects.

Masquelet Technique Combined with Ilizarov External Fixator, Reamer-irrigator-aspirator, and Flap Transplantation in an Open Tibial Fracture: A Case Report.

Introduction: The induced membrane technique was initially described by Masquelet in 1986 as a treatment for tibia non-union. It then became an established method in the management of bone defects.A critical bone defect is defined by a gap larger than 25 mm, and so, has a higher probability of non-union. Many techniques have been described to resolve this problem such as segmental bone transport, free vascular fibula graft, non-vascular fibula graft, autogenous graft, or megaprothesis. Case Report: We present the case of a 37-year-old woman who presented a multi-fragmentary open fracture of the tibia and fibula bilaterally (Gustilo-Anderson III) after a high-velocity car accident. Conclusion: The aim of this article is to demonstrate that the use of a hybrid procedure combining the Masquelet technique with the Ilizarov external fixator and reamer-irrigator-aspirator can be an effective way to treat bone defect in an open tibial fracture classified as a Gustilo-Anderson III.

Experimental research of different forms of autolyzed antigen-extracted allogeneic bone combined with vascular endothelial growth factor for the repair of bone defects.

OBJECTIVE: To investigate the effect of different forms of autolyzed antigen-extracted allogeneic(AAA) bone combined with vascular endothelial growth factor (VEGF) on bone reconstruction. METHOD: The AAA bone was made into a block and a granule shape, and mixed with VEGF to prepare VEGF bone. Establishment of rat calvarium defect animal model, it is divided into 5 groups. With block bone, granular bone, block VEGF bone, granular VEGF bone was implanted in the bone defect for repair as the experimental group. The defect area was evaluated by histological and CBCT analysis 4 weeks postoperatively. RESULTS: Postoperative 4 weeks imaging results showed that there was no high-density shadow in the bone defect area of the blank group and the volume of high-density shadow in the bone defect area of the experimental group was different. Histological results showed that no osteoblasts were found in the blank group, and new bone was formed in the experimental group. The effect of bone formation in the granular bone was better than that in the block bone, and the amount of new bone formation in the VEGF bone group was higher than that of the single bone group. CONCLUSION: Granular bone has a better osteogenesis effect than block bone. The effect of allogeneic bone combined with VEGF in promoting new bone formation in the area of the bone defect is better than that of allogeneic bone alone. These results provide a theoretical and practical basis for its further clinical application.

Application of Mg-MOF-loaded gelatin microspheres with osteogenic, angiogenic, and ROS scavenging capabilities in bone defect repair.

The management of bone defects, particularly those with irregular geometries resulting from osteoporotic fractures, remains fraught with challenges. Microspheres have emerged as a promising vehicle for tissue engineering, distinguished by their controlled release, safety, and ease of application. Various bioactive components are integrated into microspheres to improve their performance. Metal-organic frameworks, formed from metal ions interconnected by organic ligands, are increasingly utilized in tissue engineering. Specifically, magnesium-based MOFs are notable for their broad applicability; Mg2+ ions are instrumental in bone reconstruction and repair, facilitating osteogenesis, angiogenesis, antibacterial effects, and anti-inflammatory properties. Mg-MOF was synthesized using magnesium chloride and gallic acid, and it was incorporated into gelatin microspheres to create Gel@Mg-MOF composite microspheres. Leveraging gelatin's biocompatibility, controlled release, and biodegradability, the composites' biocompatibility was evaluated through toxicity and adhesion assays. Moreover, the osteogenic and angiogenic potentials of the Gel@Mg-MOF microspheres were assessed, alongside their capacity for ROS scavenging. Results suggest that controlled Mg2+ release from Gel@Mg-MOF microspheres promotes osteogenic activity in RBMSCs and enhances angiogenic potential in HUVECs. Additionally, the gallic acid-containing composite microspheres exhibited antioxidative properties. Collectively, the findings suggest that Gel@Mg-MOF microspheres could provide effective support for bone defect repair, with potential for clinical deployment.

Application of Intraoperative Individualized Cup Combination-Cup-on-Cup Technique in Severe Acetabular Defects.

This study aimed to investigate the application of the cup-on-cup technique in revision total hip arthroplasty (THA) and report clinical and radiographic outcomes from a series of case follow-ups. Retrospective analysis of 10 patients who underwent acetabular prosthesis revision with cup-on-cup technique. According to the Paprosky classification of acetabular bone defects, there were 2 cases of type II C, 3 cases of type III A, and 5 cases of type III B. The average follow-up was 54.8 ± 5.1 months, and the Harris score of the hip joint increased from 37.0 ± 9.9 preoperatively to 80.5 ± 3.1 postoperatively at the final follow-up (p < 0.001). Comparing the surgical side's hip center of rotation (COR) to the contralateral side, the preoperative average upward displacement was 33.8 ± 15.0 mm, while the postoperative average upward displacement was 0.2 ± 3.3 mm (p < 0.001). Similarly, the preoperative average inward displacement was 9.1 ± 5.1 mm, while the postoperative average outward displacement was 1.8 ± 1.6 mm (p < 0.001). There was no significant difference (p = 0.71) between the average density values of the contralateral and surgical sides at the final follow-up, which were 127.4 ± 13.7 and 125.0 ± 14.8, respectively. During the follow-up period, all patients achieved satisfactory radiographic outcomes, and no prosthetic loosening was observed. The cup-on-cup technique can reconstruct acetabular bone defects and restore hip COR in revision THA, with favorable clinical and radiographic outcomes.

Total Knee Arthroplasty With Long-Stem Implant: A Case Report of a Patient With Extreme Varus Deformity.

Constrained implants have become more common in difficult primary total knee arthroplasty (TKA) cases in recent years because they may more effectively and conveniently handle the substantial instability that is evident in osteoarthritis of knees with severe varus deformity. However, the need for a constrained TKA in such conditions is controversial, as constraint implants come with a bargain of stability for longitivity. In this case report, we have successfully shown that even in cases of significant instability and bone loss, intraoperative conversion to a restricted device is rarely necessary. In our case report, a 83-year-old female had complaints of severe pain in bilateral knees, with the right knee more than the left knee, since 12 years with severe varus deformity in the right knee. Physical examination revealed swelling and medial joint line tenderness with restriction of range of motion in bilateral knees. Pre-anesthetic checkup of the patient was done and patient was given clearance for surgery under American Society of Anesthesiologist (ASA)-2, total knee arthroplasty with a long stem was done, extreme varus deformity was corrected, osteophytes removed and tibial bone loss was repaired with bone cement. Post operatively patient showed significant improvement and McMaster University and Western Ontario Osteoarthritis Index (WOMAC) and Knee Society Scores (KSS) for pain, stiffness, and physical function during everyday activities were significantly improved compared to pre-operative assessment.

Evaluation of Biocomposite Cements for Bone Defect Repair in Rat Models.

Repairing or reconstructing significant bone defects is typically challenging. In the present study, two composite cements were used as scaffolds in a sub-critical femoral defect in rats. A control group and two experimental batches were used to compare the outcomes. This research aimed to investigate the osteogenic potential and toxicological tolerance of the bioproducts through histopathology and computed tomography imaging analysis at 14, 28, 56, and 90 days post-implantation. The biomaterials used in the investigation consisted of a 65% bioactive salinized inorganic filler and a 25% weight organic matrix. The organic part of the biomaterial was composed of Bis-GMA (bisphenol A-glycidyl methacrylate), UDMA (urethane dimethacrylate), HEMA (2-Hydroxyethyl methacrylate), and TEGDMA (triethylene glycol dimethacrylate), while the inorganic filler was composed of silica, barium glass, hydroxyapatite, and fluor aluminosilicate glass. The first findings of this research are encouraging, revealing that there is a slight difference between the groups treated with biomaterials, but it might be an effective approach for managing bone abnormalities. Material C1 exhibited a faster bone defect healing time compared to material C2, where bone fractures occurred in some individuals. It is unclear if the fractures were caused by the presence of the biomaterial C2 or whether additional variables were to blame. By the end of the research, the mice appeared to tolerate the biomaterials without exhibiting any inflammatory or rejection responses.

Enhanced osseointegration and antimicrobial properties of 3D-Printed porous titanium alloys with copper-strontium doped calcium silicate coatings.

The 3D printing of porous titanium scaffolds reduces the elastic modulus of titanium alloys and promotes osteogenic integration. However, due to the biological inertness of titanium alloy materials, the implant-bone tissue interface is weakly bonded. A calcium silicate (CS) coating doped with polymetallic ions can impart various biological properties to titanium alloy materials. In this study, CuO and SrO binary-doped CS coatings were prepared on the surface of 3D-printed porous titanium alloy scaffolds using atmospheric plasma spraying and characterized by SEM, EDS, and XRD. Both CuO and SrO were successfully incorporated into the CS coating. The in vivo osseointegration evaluation of the composite coating-modified 3D-printed porous titanium alloy scaffolds was conducted using a rabbit bone defect model, showing that the in vivo osseointegration of 2% CuO-10% SrO-CS-modified 3D-printed porous titanium alloy was improved. The in vitro antimicrobial properties of the 2% CuO-10% SrO-CS-modified 3D-printed porous titanium alloy were evaluated through bacterial platform coating, co-culture liquid absorbance detection, and crystal violet staining experiments, demonstrating that the composite coating exhibited good antimicrobial properties. In conclusion, the composite scaffold possesses both osteointegration-promoting and antimicrobial properties, indicating a broad potential for clinical applications.

Can limb length discrepancies be corrected with the Masquelet technique? A technical trick.

Masquelet technique is a well-established procedure for reconstruction of bone defects secondary to such causes as infections, non-unions, tumors or open fractures with bone loss. The management of limb length discrepancies following bone defects has been well established using bone transport and remains the preferred choice amongst reconstruction surgeons. One of the criticisms of the Masquelet technique has been its limitation to address limb length discrepancies. We describe a technique for the correction of limb length discrepancies using the Masquelet technique.

How Is Bone Regeneration Influenced by Polymer Membranes? Insight into the Histological and Radiological Point of View in the Literature.

The aim of this study was to analyze published works that investigate the in vivo bone regeneration capacity of polymeric membranes loaded with active substances and growth factors. This scoping review's purpose was to highlight the histological and radiological interpretation of the locally produced effects of the polymer membranes studied so far. For the selection of the articles, a search was made in the PubMed and ScienceDirect databases, according to the PRISMA algorithm, for research/clinical trial type studies. The search strategy was represented by the formula "((biodegradable scaffolds AND critical bone defect) OR (polymers AND mechanical properties) OR (3Dmaterials AND cytotoxicity) AND bone tissue regeneration)" for the PubMed database and "((biodegradable scaffolds AND polymers) OR (polymers AND critical bone defects) OR (biodegradable scaffolds AND mechanical properties) AND bone tissue regeneration)" for the ScienceDirect database. Ethical approval was not required. Eligibility criteria included eight clinical studies published between 2018 and 2023. Our analysis showed that polymer membranes that met most histopathological criteria also produced the most remarkable results observed radiologically. The top effective scaffolds were those containing active macromolecules released conditionally and staged. The PLGA and polycaprolactone scaffolds were found in this category; they granted a marked increase in bone density and improvement of osteoinduction. But, regardless of the membrane composition, all membranes implanted in created bone defects induced an inflammatory response in the first phase.

Biomechanical comparison shows increased stability of an arthroscopic subscapular sling procedure compared to an open Latarjet reconstruction for anterior shoulder instability in specimens with major glenoid bone defect.

Purpose: Recurrent anterior glenohumeral instability (RASI) is commonly treated with arthroscopic techniques, though their effectiveness in providing stability may diminish in cases of critical glenoid bone loss. This study aimed to compare the stability outcomes and range of motion (ROM) associated with an arthroscopic subscapular sling procedure (SSP), first introduced in 2015. Methods: Sixteen fresh-frozen human cadaveric shoulder specimens were biomechanically evaluated in four conditions: native, injured, post-SSP and post-LP. Glenohumeral translations were measured under anterior, anteroinferior and inferior loading, while external rotation ROM was assessed in neutral and abducted positions. Testing was conducted using a robotic system for precise force and torque application. Specimens were prepared with a 20% glenoid bone defect and subjected to stability testing sequentially. Results: The SSP significantly reduced glenohumeral translations compared to LP, particularly under anterior loading in neutral (p < 0.001), external rotation (p = 0.007) and abduction (p < 0.001) positions. Although the SSP demonstrated superior stability in these key positions, it did not consistently outperform the LP across all scenarios, as stability was similar between the two in the abducted and rotated position under anterior loading (p = 0.379). Under anteroinferior loading, the SSP showed comparatively better stability at neutral (p = 0.003) and abduction (p < 0.001), whereas the LP led to greater anteroinferior translations in these same positions (p = 0.002 and p = 0.014, respectively). The SSP outperformed the LP under inferior loading in neutral (p = 0.005) and abduction (p = 0.02) positions, though it did not fully restore stability to native shoulder levels. The SSP maintained ROM similar to native shoulders. LP allowed greater ROM, potentially compromising stability. Conclusion: The SSP provided greater stability than the open Latarjet in most positions and did not limit ROM, suggesting it could be a viable, less invasive option for managing shoulder instability. Level of Evidence: Not applicable.