Allogeneic Bone Grafts Research Articles

Allogeneic Bone Application in Association with Platelet-Rich Plasma for Alveolar Bone Grafting of Cleft Palate Defects.

Aim:The aim of this study is to compare allogeneic bone grafts associated with platelet-rich plasma (ALBGs-PRP) to autogenous bone grafts (ATBGs) for alveolar reconstructions in patients with cleft lip and palate (CLP).Materials and Methods:The Maxillofacial Surgery Service of the Comprehensive Care Center for CLP (CCCLP) in Curitiba (Paraná, Brazil).Patients:Thirty out of 46 patients with 8–12 years of age and pre- or trans-foramen unilateral clefts were operated by the same surgeon. Groups were selected randomly after coin-toss for the first surgery to be ALBG-PRP.Interventions:Pre- and post-surgery cleft defect severity was registered by a score system using superimposed digitalized peri-apical radiographs. The hypothesis indicated ABG-PRP to be similar to the ABG was proved.Results:There was no statistically significant difference (P < 0.05) in bone augmentation for the ABG-PRP group (79.88%) when compared to the ABG group (79.9%).Conclusion:ABG-PRP is indicated as a successful treatment modality to reduce the need for additional donor sites and reduce morbidity and hospital stay.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Compared with a Composite Grafting Material or Bone Substitute Alone: a Systematic Review and Meta-Analysis Assessing Volumetric Stability of the Grafting Material.

ABSTRACTObjectivesTest the hypothesis of no difference in the volumetric stability of the grafting material following maxillary sinus floor augmentation with autogenous bone graft compared with composite grafting material or bone substitute alone applying the lateral window technique.Material and MethodsMEDLINE (PubMed), Embase, Cochrane library and hand-search of relevant journals were conducted. Human studies published in English until the 9th of October 2020 were included. Outcome measures included three-dimensional volumetric changes of the grafting material and potential predictive parameters. Volumetric changes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval.ResultsElectronic search and hand-searching resulted in 102 entries. Four randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. The volumetric stability of the grafting material was significantly improved by mixing autogenous bone graft with a non-resorbable xenograft compared with autogenous bone graft. Meta-analyses assessing absolute and relative volumetric changes demonstrated no significant differences between autogenous bone graft compared with allogeneic bone graft, synthetic biomaterials combined with autogenous bone graft or used alone. Association between volumetric changes of the grafting material and potential predictive parameters were not assessed in the included studies.ConclusionsVolumetric reduction of the augmented area seems inevitable following maxillary sinus floor augmentation regardless of the grafting material. The volumetric stability of autogenous bone graft is improved with addition of xenograft compared with autogenous bone graft. However, conclusions drawn from this systematic review should be interpreted with caution since only four studies using three-dimensional radiographic measurements were included.

Dental Implants and Plasma Rich in Fibrine: A Wide Literary Review

&#x0D; &#x0D; &#x0D; &#x0D; Introduction: When a dental element is lost in the posterior region of the maxilla, there is natural reabsorption of the alveolar process and at the same time there will be pneumatization of the maxillary sinus. It will increase its volume towards the place where the roots existed and this will often make it difficult or impossible to restore implants in place. For this reason, the procedure for elevating the floor of the maxillary sinus or short implants should be performed when possible. In this context, allogeneic, xenogenous, and alloplastic bone grafts are an alternative for the treatment of bone defects in the jaws, since they avoid the need for a second surgical access. However, due to the need for processing to eliminate antigenic components, these grafts are only osteoconductive with a lower bone formation potential compared to autogenous bone grafts. Also, in this context, in the last 20 years, platelet concentrates have been proposed as regenerative materials in tissue regeneration procedures. Among the platelet concentrates proposed in the literature, PRP and FRP are found to act as autogenous platelet aggregates with osteoinductive properties. Objective: The present study aimed to conduct a wide literature review on maxillary sinus surgery using fibrin-rich plasma. Methods: Experimental and clinical studies (case reports, retrospective, prospective and randomized) with qualitative and/or quantitative analysis were included. Results: The total of 48 articles were found involving Maxillary sinus surgery, Fibrin-rich plasma, and Biomaterials, of which 22 were selected to compose the present study. Conclusion: Based on the literary findings, it was shown that the FRP is favorable for bone formation processes for dental implants, especially when combined with xenografts.&#x0D; &#x0D; &#x0D; &#x0D;

Bone Allograft and Locking Plate for Severe Proximal Humeral Fractures: Early and Late Outcomes.

BackgroundEarly failure of osteosyntheses is common even with use of locking plates. In patients with comminuted fractures and epiphyseal osseous defects, we performed a series of osteosyntheses by locking plate in combination with an allograft bone augmentation. Because of encouraging short-term results in the literature, we assumed that the method could be a potential alternative to a reverse shoulder prosthesis.Material/MethodsTwenty-six patients with a dislocated proximal humeral fracture (Neer IV/V/VI) were studied. A lyophilized allogeneic bone graft was used to reinforce the humeral head fragments before locking plate osteosynthesis. The outcomes of fractures were assessed with Disabilities of the Arm, Shoulder and Hand (DASH) and Constant-Murley (Constant) scores, range of motion, a visual analog scale, and with radiological testing. The Constant-Murley scores were the endpoint of our study.ResultsThe Neer classification of the fractures was type IV in 4 patients, type V in 20 patients, and type VI in 2 patients. The mean DASH score was 52.85 (range, 4.17–79.3) and the mean Constant score was 39.26 (range, 17–88). We observed late necrosis of the humeral head in 15 of 24 patients (62.5%), although early radiological follow-up showed that the humeral head had been anatomically reconstructed.ConclusionsLong-term follow-up demonstrated inferior functional results, as displayed by poor Constant scores. There was a high incidence of necrosis, in spite of initial anatomical reconstruction. Biointegration of the allogeneic bone graft and revascularization of the humeral head fragments could be impaired in geriatric patients who have gross dislocation. Therefore, augmentation of the humeral head with allogeneic bone grafts cannot be recommended in these patients.

A partially demineralized allogeneic bone graft: in vitro osteogenic potential and preclinical evaluation in two different intramembranous bone healing models

In skeletal surgical procedures, bone regeneration in irregular and hard-to-reach areas may present clinical challenges. In order to overcome the limitations of traditional autologous bone grafts and bone substitutes, an extrudable and easy-to-handle innovative partially demineralized allogenic bone graft in the form of a paste has been developed. In this study, the regenerative potential of this paste was assessed and compared to its clinically used precursor form allogenic bone particles. Compared to the particular bone graft, the bone paste allowed better attachment of human mesenchymal stromal cells and their commitment towards the osteoblastic lineage, and it induced a pro-regenerative phenotype of human monocytes/macrophages. The bone paste also supported bone healing in vivo in a guide bone regeneration model and, more interestingly, exhibited a substantial bone-forming ability when implanted in a critical-size defect model in rat calvaria. Thus, these findings indicate that this novel partially demineralized allogeneic bone paste that combines substantial bone healing properties and rapid and ease-of-use may be a promising alternative to allogeneic bone grafts for bone regeneration in several clinical contexts of oral and maxillofacial bone grafting.

An exploration on human compatible artificial bone placement through cell culture

The artificial bone replacement material showed significantly higher retention forces than actual bone samples. Trauma, cancer, ageing and genetic diseases, and tissue reconstruction causes bone defects and bone lesions. Providing mechanical and functional integrity is an important step for the bone regeneration. Using autogenic or allogeneic bone grafts conventionally accelerates bone regeneration with minimal autograft and allograft capital. While autogenous graft is considered the golden standard in restoring bone defects, the harvest may impact patients. The aim of this study was to elucidate the ability of a newly developed, high porosity unidirectional porous b-TCP artificial bone to induce regeneration of bones. The capacity of a commercially available b-TCP drug to cause bone regeneration was contrasted.Implantation in bony defects left after fibula harvesting for spinal fusion surgery as well. Innovative biomaterials with osteoinductive potential have emerged as candidates for bone repair since the discovery of osteoinduction in the early 20th century. Recently, models of artificial protocell have shown great potential for tissue regeneration. Hydroxyapatite (HAP) nanocrystallites of all forms of bones are characterized by their ultrathine properties, which are uniaxially aligned with fibrillar collagen to reveal the (100) faces in a special way. We speculate that living organisms prefer the specific crystal morphology and HAP's orientation due to interactions at the mineral-cell interface between cells and crystals. To investigate the ultrathine mineral modulating effect on cell bioactivity and bone generation, bone-like platy HAP (p-HAP) and two different rod-like HAPs have been synthesized here. The platy HAP with (100) faces significantly promoted cell viability and osteogenic differentiation of mesenchymal stem cells ( MSCs) as compared to rod-like HAPs with (001) faces as the dominant crystal orientation, indicating that MSCs could recognize the crystal face and prefer the (100) HAP faces.&#x0D; Mediscope Vol. 8, No. 1: January 2021, Page 7-18

Exosome-Derived Noncoding RNAs as a Promising Treatment of Bone Regeneration.

The reconstruction of large bone defects remains a crucial challenge in orthopedic surgery. The current treatments including autologous and allogenic bone grafting and bioactive materials have their respective drawbacks. While mesenchymal stem cell (MSC) therapy may address these limitations, growing researches have demonstrated that the effectiveness of MSC therapy depends on paracrine factors, particularly exosomes. This aroused great focus on the exosome-based cell-free therapy in the treatment of bone defects. Exosomes can transfer various cargoes, and noncoding RNAs are the most widely studied cargo through which exosomes exert their ability of osteoinduction. Here, we review the research status of the exosome-derived noncoding RNAs in bone regeneration, the potential application of exosomes, and the existing challenges.

Reliability of Goldberg Scoring System in the Radiographic Evaluation of Bony Union after Bone Grafting.

BackgroundEvaluation of bony union after bone grafting is very important in orthopedic surgery. The aim of this study was to verify inter- and intraobserver reliability of the Goldberg scoring system for radiographic evaluation of bony union after bone grafting in various situations of animal models.MethodsTwenty-seven male C57/BL6 mice, which lack the ability to synthesize galactose-alpha-1,3-galactose (GalT KO mice), and 9 C57/BL6 mice carrying a wild-type gene were used as animal models. We divided the mice into four groups. In group 1, syngenic bone grafting and intramedullary fixation were performed (9 wild type C57BL/6 mice). In group 2, allogenic bone grafting was performed (9 GalT KO mice). In group 3, an alpha-galactosidase-treated porcine xenograft was transplanted into the femur to reduce the antigenicity (9 GalT KO mice). In group 4, a non-treated porcine xenobone grafting was performed (9 GalT KO mice). The level of radiographic bony union (Goldberg method) was assessed by three orthopedic surgeons. Intra- and interobserver reliability for radiographic evaluation was assessed.ResultsIn the Goldberg scoring system, most of the radiographic measurements showed substantial to almost perfect intraobserver reliability. The total score showed substantial intraobserver reliability. The kappa coefficient (κ) of the first examiner was 0.603, the κ of the second examiner was 0.790, and the κ of the third examiner was 0.758. The scoring system showed substantial interobserver reliability. The κ of the first session was 0.641 and the κ of the second session was 0.649.ConclusionsThe Goldberg scoring system is a reliable tool for radiographic evaluation of bony union after bone grafting.

Artroskopski asistirana osteosinteza preloma platoa tibije Šacker III tipa - prikaz slučaja

Introduction. Tibial plateau fractures are complex injuries that, in most cases, require surgical treatment in order to prevent far-reaching consequences for the functionality and quality of life of the patient. While numerous surgical techniques have been described, it is evident that the technique of arthroscopically assisted repositioning (reduction) and internal fixation has the potential to take the lead in the management of these types of injuries. Case report. We present the case of a 36-year-old patient injured in a traffic accident with a fracture of the left tibial plateau, type III by Schatzker classification. After the diagnostic procedures and preparation, the patient was operated on using arthroscopically assisted repositioning (reduction) and internal fixation, with the filling of the bone defect with a combination of allogenic and synthetic bone graft. No other intra-articular injuries were diagnosed intraoperatively. The postoperative recovery went without complications, and after a period of 10 weeks of non-weight bearing and functional rehabilitation, the fracture healed completely, while the patient regained full range of motion in the knee. Conclusion. Although this type of injury has traditionally been treated with open surgery, we believe that minimally invasive surgery is the future, when it comes to tibial plateau fractures Schatzker types I-III. There is still not enough data in the literature regarding the long-term outcomes of this type of treatment, but the early postoperative results are extremely encouraging since this surgical technique enables faster recovery and fewer postoperative complications.

Transition from Secondary Blood Test to Nucleic Acid Amplification for Safe Allograft Transplantation.

BackgroundGiven the incubation period of viral diseases, a secondary blood test should be performed at least 3–6 months after the first test to ensure the safety of allogenic bone grafts obtained from living donors in some tissue banks. The allograft is discarded if a secondary blood test was unavailable. The secondary blood test can be replaced with a nucleic acid amplification test (NAT) to reduce the discarded allograft. The purpose of this study was to analyze the comparative efficiency of secondary blood test and NAT to determine the donor suitability of allogenic bone grafts.MethodsAllogenic bones were retrieved from 452 living donors between January 2013 and December 2019. A secondary blood test was conducted in 182 patients and NAT was performed in 270 patients. The average age of donors was 69 years (range, 33–87 years). They included 86 men and 366 women. The initial blood tests including hepatitis B, hepatitis C, AIDS, and syphilis were conducted before retrieving grafts. The results were analyzed after the secondary blood test was performed at least 3 to 6 months after the first test because of the incubation period of the viral diseases. NAT was performed within 2 months after the first blood test.ResultsSixty-seven of the 452 cases (14.8%) were discarded. In the secondary blood test group, 50 out of 182 cases (27.4%), and in the NAT group, 17 out of 270 cases (6.3%) were discarded. None of the 132 donors tested positive in the secondary blood test after testing negative in the first test.ConclusionsIt is extremely rare that the secondary blood test yields positive results in donors who tested negative in the initial test. However, quite a few grafts are discarded only because the secondary blood test is not available. In terms of economics and ethics, the secondary blood test may not be necessary or if required, a single test such as NAT for infectious diseases may be performed to determine donor suitability of allogenic bone.

In Vitro and In Vivo Study of a Novel Nanoscale Demineralized Bone Matrix Coated PCL/β-TCP Scaffold for Bone Regeneration.

Bone defects remains a challenge for surgeons. Bone graft scaffold can fill the defect and enhance the bone regeneration. Demineralized bone matrix (DBM) is an allogeneic bone graft substitute, which can only be used as a filling material rather than a structural bone graft. Coating of the scaffolds with nanoscale DBM may enhance the osteoinductivity or osteoconductivity. Herein the lyophilization method is presented to coat the nano-DBM on surface of the porous polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP) scaffolds fabricated by 3D printing technology. The morphology, elastic modulus, in vitro cell biocompatibility, and in vivo performance are investigated. Scanning electron microscope (SEM) shows DBM particle clusters with size of 200-500nm are observed on scaffolds fibers after coating. MC3T3-E1 cells on nano-DBM coated PCL/β-TCP scaffold show better activity than on PCL/β-TCP scaffold. In vivo tests show better infiltration of new bone tissue in nano-DBM coated PCL/β-TCP scaffold than PCL/β-TCP scaffold via the interface. These results show the presence of nano-DBM coating on PCL/β-TCP scaffold could enhance the attachment, proliferation, and viability of cells and benefit for the new bone formation surrounding and deep inside the scaffolds. Nano-DBM could potentially be used as a new kind of biomaterial for bone defect treatment.

Synthetic Polymeric Materials for Bone Replacement

Some treatment options available to repair bone defects are the use of autogenous and allogeneic bone grafts. The drawback of the first one is the donor site’s limitation and the need for a second operation on the same patient. In the allograft method, the problems are associated with transmitted diseases and high susceptibility to rejection. As an alternative to biological grafts, polymers can be used in bone repair. Some polymers used in the orthopedic field are poly(methyl methacrylate), poly(ether-ether-ketone), and ultra-high molecular weight polyethylene (UHMWPE). UHMWPE has drawn much attention since it combines low friction coefficient and high wear and impact resistance. However, UHMWPE is a bioinert material, which means that it does not interact with the bone tissue. UHMWPE composites and nanocomposites with hydroxyapatite (HA) are widely studied in the literature to mitigate these issues. HA is the main component of the inorganic phase in the natural bone, and the addition of this bioactive filler to the polymeric matrix aims to mimic bone composition. This brief review discusses some polymers used in orthopedic applications, focusing on the UHMWPE/HA composites as a potential bone substitute.

Clinical observation of mineralized collagen bone grafting after curettage of benign bone tumors.

Curettage of benign bone tumor is a common cause for bone defect. For such bone defect repair, autogenous bone, allogeneic bone and traditional artificial bone graft substitutes have many disadvantages. In recent years, a biomimetic mineralized collagen (MC) with similar composition and microstructures to the natural bone matrix was developed and used for treating various bone defects. In this work, a retrospective study analyzed clinical outcomes of patients treated with curettage of benign bone tumors and bone grafting with MC, in comparison to another group treated with the same surgical method and autogenous bone. Lane–Sandhu X-ray score of the autogenous bone group was superior to the MC group at 1 month after the operation, but the two groups had no statistical difference at 6 and 12 months. The MC group was better in Musculoskeletal Tumor Society scoring at 1 and 6 months after the operation, and the two groups had no statistical difference at 12 month. Therefore, the MC performed not as good as autogenous bone in early stage of bone healing but achieved comparable outcomes in long-term follow-ups. Moreover, the MC has advantages in function recovery and avoided potential complications induced by harvesting autogenous bone.

A review of biomimetic scaffolds for bone regeneration: Toward a cell-free strategy.

In clinical terms, bone grafting currently involves the application of autogenous, allogeneic, or xenogeneic bone grafts, as well as natural or artificially synthesized materials, such as polymers, bioceramics, and other composites. Many of these are associated with limitations. The ideal scaffold for bone tissue engineering should provide mechanical support while promoting osteogenesis, osteoconduction, and even osteoinduction. There are various structural complications and engineering difficulties to be considered. Here, we describe the biomimetic possibilities of the modification of natural or synthetic materials through physical and chemical design to facilitate bone tissue repair. This review summarizes recent progresses in the strategies for constructing biomimetic scaffolds, including ion‐functionalized scaffolds, decellularized extracellular matrix scaffolds, and micro‐ and nano‐scale biomimetic scaffold structures, as well as reactive scaffolds induced by physical factors, and other acellular scaffolds. The fabrication techniques for these scaffolds, along with current strategies in clinical bone repair, are described. The developments in each category are discussed in terms of the connection between the scaffold materials and tissue repair, as well as the interactions with endogenous cells. As the advances in bone tissue engineering move toward application in the clinical setting, the demonstration of the therapeutic efficacy of these novel scaffold designs is critical.

Surgical treatment of benign lesions and pathologic fractures of the proximal femur in children.

Benign lesions of the proximal femur region, such as simple bone cysts, aneurysmal bone cysts, and fibrous dysplasia, are common in children. Benign lesions may cause pathologic fractures, limb length inequities, and growth disturbances. Differential diagnoses, e.g., malignant bone tumors and osteomyelitis, are sometimes difficult to rule out. We aimed to evaluate outcomes in children with benign lesions of the proximal femur treated with curettage, bone grafting, and plate fixation. In this retrospective study, we included 30 children (median age 10.5years; range 1.1-17.8years) suffering from bone cysts and tumor-like lesions of the proximal femur region treated between 2002 and 2018. We analyzed plain X-ray images and CT scans in all children and obtained MRI scans in a selected group of children (63.3%). We examined histopathologic biopsy results for all bone lesions before initiating treatment. Surgical management comprised tumor curettage with adjuvant high-speed drilling and allogenic bone grafting supplemented by bone graft substitutes before plate fixation. Median follow-up interval was 87months (range 24-156months). We evaluated the healing of lesions according to Capanna's classification and rated functional outcomes according to Merle d'Aubigné and Postel score. Overall, 25 of 30 (83.3%) patients were admitted to hospital because of a pathologic fracture. We diagnosed simple bone cysts in 15 (50.0%) patients, aneurysmal bone cysts in 7 (23.5%) patients, and fibrous dysplasia in 8 (26.5%) patients. Bone consolidation was achieved in 22 of 30 (73.3%) patients after a mean of 5months (range 3-7months). The main complication was recurrence of the lesion in 4 of 30 (13.3%) patients. With respect to the Merle d'Aubigné and Postel scores, 17 of 30 (56.7%) patients obtained an excellent result (18 points), while 12 (40.0%) patients had a good result (15-17 points) and only 1 (3.3%) patient had a fair result (14 points). Surgical treatment of bone cysts and tumor-like lesions of the proximal femur by local resection or destruction of the lesion, followed by filling the defect with bone graft material and internal stabilization represents a safe and effective treatment option in children. Therapeutic, retrospective comparative study-Level III.

Clinical study on bilamina cortical grafting technique for reconstruction of severely atrophic alveolar ridges in anterior maxillae

Objective: To evaluate the efficacy and long-term outcome of the bilaminar cortical wall building grafting technique for reconstruction of vertical and horizontal alveolar ridge defects in the esthetic zone. Methods: The retrospective study was conducted between January, 2007 and December, 2015. The sample was composed of 24 patients who received bilaminar cortical wall building augmentation in the esthetic zone in Department of Fourth Clinical Division, Peking University School of Stomatology. The 24 patients (11 female and 13 male) had age of (37.8±13.4) years (20-54 years). A bone block harvested from the lateral aspect of the mandibular ramus was bisected into two cortical laminae, which were then used to reconstruct the buccal and palatal walls of an alveolar ridge defect. The inter-laminar space was filled with particulate autogenous bone and the whole graft was covered with anorganic bone graft and collagen membrane. Bone width and vertical measurements were measured at the time of surgery and reentry surgery. Integration of the graft, implant survival rates and complications were recorded. Results: Overall, 24 patients with 35 sites who were included were followed for (7.1±1.9) years. Graft integration (24/24) and implant survival rates (35/35) were determined as 100%. The average horizontal and vertical bone gain was (6.47±2.46) and (5.01±1.12) mm with resorption rates of 9.0% and 10.9%, respectively. One patient showed soft-tissue dehiscence with peri-implant mucositis were observed 9 years after surgery. More than 1.5 mm of buccal bone plate were observed using cone beam computed tomography. Conclusions: This technique was effective and reliable for three-dimensional reconstruction of severely atrophic alveolar ridges in anterior maxillae. Autogenous graft combined with coverage by allogeneic bone graft and collagen membrane provided successful augmentation with low bone resorption.

Effect of biologic materials on the outcomes of horizontal alveolar ridge augmentation: A retrospective study.

PurposeThe purpose of this study was to investigate if the addition of biologic agents to a particulate bone graft enhances horizontal ridge augmentation outcomes in terms of bone dimensions, bone density, and successful implant placement.Materials and MethodsA retrospective chart review was done to assess the clinical and radiographic outcomes in 52 horizontal ridge augmentation sites in 43 patients. Information was gathered regarding surgical technique, type of graft material, biologic agents used (PRP or rhPDGF‐BB), method of space maintenance, and achieved alveolar ridge width and bone density changes as quantified on CBCT scans.ResultsThe use of tenting screws, a resorbable membrane, and a combination of particulate allogenic and xenogenic bone graft material provided an average horizontal bone gain of 3.6 mm in the 52 augmented sites. There was no statistically significant difference observed in the amount of horizontal bone gain between sites treated with the addition of biologic agents (n = 21), or with a particulate bone graft alone (n = 31). A marginally statistically significant difference was found in the density of the grafted bone with the addition of biologics (p value = .0653).ConclusionThe addition of biologic agents to the graft materials did not have a significant effect on the amount of horizontal bone gain or successful implant placement; however, it marginally enhanced the bone density of the grafted area.

Scaffolds with controlled release of pro-mineralization exosomes to promote craniofacial bone healing without cell transplantation

Biomimetic bone regeneration methods which demonstrate both clinical and manufacturing feasibility, as alternatives to autogenic or allogenic bone grafting, remain a challenge to the field of tissue engineering. Here, we report the pro-osteogenic capacity of exosomes derived from human dental pulp stem cells (hDPSCs) to facilitate bone marrow stromal cell (BMSC) differentiation and mineralization. To support their delivery, we engineered a biodegradable polymer delivery platform to improve the encapsulation and the controlled release of exosomes on a tunable time scale from poly(lactic-co-glycolic acid) (PLGA) and poly(ethylene glycol) (PEG) triblock copolymer microspheres. Our delivery platform integrates within three-dimensional tissue engineering scaffolds to enable a straightforward surgical insertion into a mouse calvarial defect. We demonstrate the osteogenic potential of these functional constructs in vitro and in vivo. Controlled release of osteogenic hDPSC-derived exosomes facilitates osteogenic differentiation of BMSCs, leading to mineralization to a degree which is comparable to exogenous administration of the same exosomes in human and mouse BMSCs. By recruiting endogenous cells to the defects and facilitating their differentiation, the controlled release of osteogenic exosomes from a tissue engineering scaffold demonstrates accelerated bone healing in vivo at 8 weeks. Exosomes recapitulate the advantageous properties of mesenchymal stem/progenitor cells, without manufacturing or immunogenic concerns associated with transplantation of exogenous cells. This biomaterial platform enables exosome-mediated bone regeneration in an efficacious and clinically relevant way.

Radiographic Union of Evans Osteotomy Without Fixation

Category:Hindfoot; OtherIntroduction/Purpose:The Evans osteotomy is a lateral column lengthening procedure of the calcaneus that is commonly used to correct flexible flatfoot deformities. There is no consensus on whether fixation is needed to avoid nonunion and calcaneocuboid subluxation when performing this osteotomy. We assessed the nonunion rate and correlated extent of subluxation with graft size in an unfixed Evans osteotomy with an allograft wedge and no pinning of the calcaneocuboid joint at any point in the largest series of the procedure to date. Surgeries were performed in patients undergoing flexible flatfoot reconstruction.Methods:We retrospectively reviewed 120 consecutive patients who had undergone 145 unfixed Evans osteotomies by a single surgeon with allogenic bone graft for flatfoot reconstruction between January 2013 and October 2017, with a mean follow-up of 62.5 (range 9.4-266.7) weeks. The calcaneocuboid joint was not pinned during the procedure. Data were collected using clinical and radiographical examination during regular follow-up.Results:A total of 137 feet (94.5%) underwent a double calcaneal osteotomy with an associated medial displacement calcaneal osteotomy (MDCO). There was one nonunion (0.69%). The mean time to union was 10.8 (range, 6.7-17.9) weeks. There was significant improvement in all radiographic parameters postoperatively, including calcaneal pitch, talonavicular uncoverage, anteroposterior and lateral talo-first metatarsal angle, lateral column length, and naviculocuboid overlap (p<0.05). Minor postoperative calcaneocuboid joint subluxation (1.51 +- 2.3 mm) occurred in 72 of 118 feet (61.0%) and had no correlation with wedge size (r=0.06; 95% CI, -0.13, 0.24; p=0.6).Conclusion:An unfixed Evans osteotomy for symptomatic flatfoot deformity resulted in a significant improvement in the radiographic alignment of the foot with an exceptionally rare nonunion rate. Detectable calcaneocuboid subluxation was common but minimal in extent and was not correlated with wedge size in this series in which wedges were less than 12 mm in the maximum dimension. This report represents the largest series of the Evans procedure to date.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Alone Compared with Alternate Grafting Materials: a Systematic Review and Meta-Analysis Focusing on Histomorphometric Outcome.

ABSTRACTObjectivesThe objective of present systematic review was to test the hypothesis of no difference in histomorphometric outcome after maxillary sinus floor augmentation with autogenous bone graft alone compared with alternate grafting materials applying the lateral window technique.Material and MethodsMEDLINE (PubMed), Embase and Cochrane library search in combination with hand-search of relevant journals were conducted. Human studies published in English until the 25th of March, 2020 were included. Histomorphometric outcomes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval (CI).ResultsElectronic search and hand-searching resulted in 1902 entries. Sixteen randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. Descriptive statistics showed comparable or improved histomorphometric outcomes with autogenous bone graft. Meta-analysis revealed a mean difference of -7.1% (CI = -11.0 to -3.2) indicating a significant higher amount of bone after maxillary sinus floor augmentation with autogenous bone graft compared with alternate grafting materials. Subgroup analysis demonstrated a non-significantly differences of -3.7% (CI = -10.9 to 3.4), -11.5% (CI = -25.9 to 2.8), 2.2% (CI = -16.9 to 21.3), and -4.6% (CI = -14.4 to 5.2), when autogenous bone graft was compared with allogeneic bone graft, xenograft, composite grafting materials involving xenograft or synthetic biomaterial mixed with autogenous bone graft, respectively.ConclusionsMaxillary sinus floor augmentation with autogenous bone graft seems to facilitate improved histomorphometric outcomes compared with alternate grafting materials. However, the included studies were characterised by an unclear risk of bias and various methodological confounding factors. Hence, the conclusions drawn from the results of present study should be interpreted with caution.