Unicystic ameloblastoma (UAM) of the jaw can be effectively reduced in volume through decompression, which promotes bone regeneration and restores jaw symmetry. This study quantitatively evaluated changes in mandible volume and symmetry following decompression of mandibular UAM. This study included 17 patients who underwent surgical decompression followed by second-stage curettage for mandibular UAM. Preoperative and postoperative three-dimensional computed tomography (CT) images were collected. Bone volume and the area of cortical perforation were measured to assess bone growth during decompression. Mandibular volumetric symmetry was analyzed by calculating the volumetric ratio of the two sides of the mandible. Twelve pairs of landmarks were identified on the surface of the lesion regions, and their coordinates were used to calculate the mean asymmetry index (AI) of the mandible. Paired t-tests and the Mann-Whitney U test were used for statistical analysis, with p < 0.05 considered indicative of statistical significance. The mean duration of decompression was 9.41 ± 3.28 months. The mean bone volume increased by 8.07 ± 2.41%, and cortical perforation recovery was 71.97 ± 14.99%. The volumetric symmetry of the mandible improved significantly (p < 0.05), and a statistically significant decrease in AI was observed (p < 0.05). In conclusion, UAM decompression enhances bone growth and symmetry recovery of the mandible. The present evaluation technique is clinically useful for quantitatively assessing mandibular asymmetry.

BACKGROUND: The search to optimize the healing and bone repair processes in oral and maxillofacial surgeries reflects the constant evolution in clinical practice, driven by the demand for increasingly satisfactory results and the need to minimize postoperative complications.
OBJECTIVE: To evaluate the efficacy of Platelet and Leukocyte Rich Fibrin (L-PRF) in the healing and bone repair process in oral and maxillofacial surgeries.
METHODS: The systematic review protocol for this study included the definition of the research question, the domain of the study, the databases searched, the search strategy, the inclusion and exclusion criteria, the types of studies to be included, the measures of effect, the methods for screening, data extraction and analysis, and the approach to data synthesis. Systematic literature searches were carried out on Cochrane databases, Web of Science, PubMed, ScienceDirect, Embase and Google Scholar.
RESULTS: The strategic search in the databases identified 1,159 studies. After removing the duplicates with the Rayyan© software, 946 articles remained. Of these, 30 met the inclusion criteria. After careful evaluation based on the inclusion and exclusion criteria, 8 studies were considered highly relevant and included in the systematic review.
CONCLUSIONS: Platelet and Leukocyte Rich Fibrin (L-PRF) has a positive effect on the healing process and bone repair in oral and maxillofacial surgeries.

Approximately 5%-10% of fractures go on to delayed healing and nonunion, posing significant clinical, economic, and social challenges. Current treatment methods involving open bone harvesting and grafting are associated with considerable pain and potential morbidity at the donor site. Hence, there is growing interest in minimally invasive approaches such as bone marrow aspirate concentrate (BMAC), which contains mesenchymal stromal cells (MSCs), macrophages (Mφ), and T cells. However, the use of cultured or activated cells for treatment is not yet FDA-approved in the United States, necessitating further exploration of optimal cell types and proportions for effective bone formation. As our understanding of osteoimmunology advances, it has become apparent that factors from anti-inflammatory Mφ (M2) promote bone formation by MSCs. Additionally, M2 Mφ promote T helper 2 (Th2) cells and Treg cells, both of which enhance bone formation. In this study, we investigated the interactions among MSCs, Mφ, and T cells in bone formation and explored the potential of subsets of BMAC. Coculture experiments were conducted using primary MSCs, Mφ, and CD4+ T cells at specific ratios. Our results indicate that nonactivated T cells had no direct influence on osteogenesis by MSCs, while coculturing MSCs with Mφ and T cells at a ratio of 1:5:10 positively impacted bone formation. Furthermore, higher numbers of T cells led to increased M2 polarization and a higher proportion of Th2 cells in the early stages of coculture. These findings suggest the potential for enhancing bone formation by adjusting immune and mesenchymal cell ratios in BMAC. By understanding the interactions and effects of immune cells on bone formation, we can develop more effective strategies and protocols for treating bone defects and nonunions. Further studies are needed to investigate these interactions in vivo and explore additional factors influencing MSC-based therapies.

Periodontitis is an inflammatory disease characterized by the destruction of periodontal tissues, and the promotion of bone tissue regeneration is the key to curing periodontitis. Psoralen is the main component of Psoralea corylifolia Linn, and has multiple biological effects, including anti-osteoporosis and osteogenesis. We constructed a novel hydrogel loaded with psoralen (PSO) and stromal cell-derived factor-1 (SDF-1) for direct endogenous cell homing. This study aimed to evaluate the synergistic effects of PSO/SDF-1 on periodontal bone regeneration in patients with periodontitis. The results of CCK8, alkaline phosphatase (ALP) activity assay, and Alizarin Red staining showed that PSO/SDF-1 combination treatment promoted cell proliferation, chemotaxis ability, and ALP activity of PDLSCs. qRT-PCR and western blotting showed that the expression levels of alkaline phosphatase (ALP), dwarf-associated transcription factor 2 (RUNX2), and osteocalcin (OCN) gene were upregulated. Rat periodontal models were established to observe the effect of local application of the composite hydrogel on bone regeneration. These results proved that the PSO/SDF-1 combination treatment significantly promoted new bone formation. The immunohistochemical (IHC) results confirmed the elevated expression of ALP, RUNX2, and OCN osteogenic genes. PSO/SDF-1 composite hydrogel can synergistically regulate the biological function and promote periodontal bone formation. Thus, this study provides a novel strategy for periodontal bone regeneration.

Bone defects resulting from trauma, illness or congenital abnormalities represent a significant challenge to global health. Conventional treatments such as autographs and allografts have limitations, leading to the exploration of bone tissue engineering (BTE) as an alternative approach. This review aims to provide a comprehensive analysis of bone regeneration mechanisms with a focus on the role of chitosan-based biomaterials and mesenchymal stem cells (MSCs) in BTE. In addition, the physiochemical and biological properties of chitosan, its potential for bone regeneration when combined with other materials and the mechanisms through which MSCs facilitate bone regeneration were investigated. In addition, different methods of scaffold development and the incorporation of MSCs into chitosan-based scaffolds were examined. Chitosan has remarkable biocompatibility, biodegradability and osteoconductivity, making it an attractive choice for BTE. Interactions between transcription factors such as Runx2 and Osterix and signaling pathways such as the BMP and Wnt pathways regulate the differentiation of MSCs and bone regeneration. Various forms of scaffolding, including porous and fibrous injections, have shown promise in BTE. The synergistic combination of chitosan and MSCs in BTE has significant potential for addressing bone defects and promoting bone regeneration, highlighting the promising future of clinical challenges posed by bone defects.

Fabrication of porous tissue-engineering scaffolds from bioactive glasses (BAG) is complicated by the tendency of BAG compositions to crystallize in thermal treatments during scaffold manufacture. Here, experimental biocompatible glass S59 (SiO2 59.7 wt%, Na2O 25.5 wt%, CaO 11.0 wt%, P2O5 2.5 wt%, B2O3 1.3 wt%), known to be resistant to crystallization, was used in sintering of glass granules (300-500 µm) into porous scaffolds. The dissolution behavior of the scaffolds was then studied in vivo in rabbit femurs and under continuous flow conditions in vitro (14 days in vitro/56 days in vivo). The scaffolds were osteoconductive in vivo, as bone could grow into the scaffold structure. Still, the scaffolds could not induce sufficiently rapid bone ingrowth to replace the strength lost due to dissolution. The scaffolds lost their structure and strength as the scaffold necks dissolved. In vitro, S59 dissolved congruently throughout the 14-day experiments, resulting in only a slight reaction layer formation. Manufacturing BAG scaffolds from S59 that retain their amorphous structure was thus possible. The relatively rapid and stable dissolution of the scaffold implies that the glass S59 may have the potential to be used in composite implants providing initial strength and stable, predictable release of ions over longer exposure times.

UNASSIGNED: The deployment of bone grafts (BGs) is critical to the success of scaffold-guided bone regeneration (SGBR) of large bone defects. It is thus critical to provide harvesting devices that maximize osteogenic capacity of the autograft while also minimizing graft damage during collection. As an alternative to the Reamer-Irrigator-Aspirator 2 (RIA 2) system - the gold standard for large-volume graft harvesting used in orthopaedic clinics today - a novel intramedullary BG harvesting concept has been preclinically introduced and referred to as the ARA (aspirator + reaming-aspiration) concept. The ARA concept uses aspiration of the intramedullary content, followed by medullary reaming-aspiration of the endosteal bone. This concept allows greater customization of BG harvesting conditions vis-à-vis the RIA 2 system. Following its successful in vitro validation, we hypothesized that an ARA concept-collected BG would have comparable in vivo osteogenic capacity compared to the RIA 2 system-collected BG.
UNASSIGNED: We used 3D-printed, medical-grade polycaprolactone-hydroxyapatite (mPCL-HA, wt 96 %:4 %) scaffolds with a Voronoi design, loaded with or without different sheep-harvested BGs and tested them in an ectopic bone formation rat model for up to 8 weeks.
UNASSIGNED: Active bone regeneration was observed throughout the scaffold-BG constructs, particularly on the surface of the bone chips with endochondral bone formation, and highly vascularized tissue formed within the fully interconnected pore architecture. There were no differences between the BGs derived from the RIA 2 system and the ARA concept in new bone volume formation and in compression tests (Young\'s modulus, p = 0.74; yield strength, p = 0.50). These results highlight that the osteogenic capacities of the mPCL-HA Voronoi scaffold loaded with BGs from the ARA concept and the RIA 2 system are equivalent.
UNASSIGNED: In conclusion, the ARA concept offers a promising alternative to the RIA 2 system for harvesting BGs to be clinically integrated into SGBR strategies.
UNASSIGNED: Our results show that biodegradable composite scaffolds loaded with BGs from the novel intramedullary harvesting concept and the RIA 2 system have equivalent osteogenic capacity. Thus, the innovative, highly intuitive intramedullary harvesting concept offers a promising alternative to the RIA 2 system for harvesting bone grafts, which are an important component for the routine translation of SGBR concepts into clinical practice.

UNASSIGNED: Salidroside (SAL) is the most effective component of Rhodiola rosea, a traditional Chinese medicine. Cryptotanshinone (CT) is the main fat-soluble extract of Salvia miltiorrhiza, exhibiting considerable potential for application in osteogenesis. Herein, a polycaprolactone/gelatin nanofiber membrane loaded with CT and SAL (PSGC membrane) was successfully fabricated via coaxial electrospinning and characterized.
UNASSIGNED: This membrane capable of sustained and controlled drug release was employed in this study. Co-culturing the membrane with bone marrow mesenchymal stem cells and human umbilical vein endothelial cells revealed excellent biocompatibility and demonstrated osteogenic and angiogenic capabilities. Furthermore, drug release from the PSGC membrane activated the Wnt/β-catenin signaling pathway and promoted osteogenic differentiation and vascularization. Evaluation of the membrane\'s vascularization and osteogenic capacities involved transplantation onto a rat\'s subcutaneous area and assessing rat cranium defects for bone regeneration, respectively. Microcomputed tomography, histological tests, immunohistochemistry, and immunofluorescence staining confirmed the membrane\'s outstanding angiogenic capacity two weeks post-operation, with a higher incidence of osteogenesis observed in rat cranial defects eight weeks post-surgery.
UNASSIGNED: Overall, the SAL- and CT-loaded coaxial electrospun nanofiber membrane synergistically enhances bone repair and regeneration.

BACKGROUND: Repairation of bone defects remains a major clinical problem. Constructing bone tissue engineering containing growth factors, stem cells, and material scaffolds to repair bone defects has recently become a hot research topic. Nerve growth factor (NGF) can promote osteogenesis of bone marrow mesenchymal stem cells (BMSCs), but the low survival rate of the BMSCs during transplantation remains an unresolved issue. In this study, we investigated the therapeutic effect of BMSCs overexpression of NGF on bone defect by inhibiting pyroptosis.
METHODS: The relationship between the low survival rate and pyroptosis of BMSCs overexpressing NGF in localized inflammation of fractures was explored by detecting pyroptosis protein levels. Then, the NGF+/BMSCs-NSA-Sca bone tissue engineering was constructed by seeding BMSCs overexpressing NGF on the allograft bone scaffold and adding the pyroptosis inhibitor necrosulfonamide(NSA). The femoral condylar defect model in the Sprague-Dawley (SD) rat was studied by micro-CT, histological, WB and PCR analyses in vitro and in vivo to evaluate the regenerative effect of bone repair.
RESULTS: The pyroptosis that occurs in BMSCs overexpressing NGF is associated with the nerve growth factor receptor (P75NTR) during osteogenic differentiation. Furthermore, NSA can block pyroptosis in BMSCs overexpression NGF. Notably, the analyses using the critical-size femoral condylar defect model indicated that the NGF+/BMSCs-NSA-Sca group inhibited pyroptosis significantly and had higher osteogenesis in defects.
CONCLUSIONS: NGF+/BMSCs-NSA had strong osteogenic properties in repairing bone defects. Moreover, NGF+/BMSCs-NSA-Sca mixture developed in this study opens new horizons for developing novel tissue engineering constructs.

BACKGROUND: This study aimed to identify glycine analogs conducive to the formation of cell-absorbable nanocomplexes, enhancing collagen synthesis and subsequent osteogenesis in combination with BMP2 for improved bone regeneration.
METHODS: Glycine and its derivatives were assessed for their effects on osteogenic differentiation in MC3T3-E1 cells and human bone marrow mesenchymal stem cells (BMSCs) under osteogenic conditions or with BMP2. Osteogenic differentiation was assessed through alkaline phosphatase staining and real-time quantitative polymerase chain reaction (RT-qPCR). Nanocomplex formation was examined via scanning electron microscopy, circular dichroism, and ultraviolet-visible spectroscopy. In vivo osteogenic effects were validated using a mouse calvarial defect model, and bone regeneration was evaluated through micro-computed tomography and histomorphometric analysis.
RESULTS: Glycine, glycine methyl ester, and glycinamide significantly enhanced collagen synthesis and ALP activity in conjunction with an osteogenic medium (OSM). GA emerged as the most effective inducer of osteoblast differentiation marker genes. Combining GA with BMP2 synergistically stimulated ALP activity and the expression of osteoblast markers in both cell lines. GA readily formed nanocomplexes, facilitating cellular uptake through strong electrostatic interactions. In an in vivo calvarial defect mouse model, the GA and BMP2 combination demonstrated enhanced bone volume, bone volume/tissue volume ratio, trabecular numbers, and mature bone formation compared to other combinations.
CONCLUSIONS: GA and BMP2 synergistically promoted in vitro osteoblast differentiation and in vivo bone regeneration through nanocomplex formation. This combination holds therapeutic promise for individuals with bone defects, showcasing its potential for clinical intervention.