جستجوی مقالات مرتبط با کلیدواژه « ترمیم استخوان » در نشریات گروه « دامپزشکی »

One of the most common concerns in the regeneration of massive bone defects necessitating surgery and bone grafts is the application of tissue engineering using drug delivery. Zoledronate is a well-known effective drug for the healing bone fractures in osteoporotic patients.

An attempt was made to design a more efficient bone scaffold with polycaprolactone, polylactic acid, and hydroxyapatite.

The scaffold was fabricated by freeze-drying and indirect 3D printing approaches. X-ray diffraction, Fourier transform infrared spectroscopy, rheometry, scanning electron microscopy, and neutral red tests were performed to characterize the scaffold. qRT-PCR was also done to define the osteoinductivity and angiogenic induction capacity of this scaffold. Forty rats were selected and randomly divided into four groups: the control group, which received no treatment, the autograft group, scaffold group, and Zol-loaded scaffold group (n=10 in each group). The injured area was studied by radiology, biomechanical analysis, histopathology, histomorphometry, immunohistochemistry, and CT scan analyses.

The qRT-PCR results demonstrated significantly higher expression levels of OPN, OCN, and CD31 markers in the scaffold group when compared to the control group (P<0.05). Histopathologically, the newly formed bone tissue was significantly detected in the Zol-loaded scaffold and autograft groups in comparison with the non-treated group (P<0.001). The immunohistochemistry (OC marker), biomechanical, and histomorphometric results indicated a significant improvement in the regeneration of the injured area in the groups treated with autologous bone and Zol-loaded scaffold compared to the non-treated group (P<0.05).

The Zol-loaded scaffold accelerated bone regeneration, and led to enhanced structural performance and functional ability of the injured radial bone in rats.

Fracture repair is a complex biological process that requires the cooperation of various types of cells and materials. Today, various techniques such as low-density pulse ultrasonography and electrical stimulation are used to accelerate bone healing. The therapeutic effects of ozone on bone repair have been considered in recent years. The purpose of this study was to evaluate the effect of ozone gas on the speed of full-thickness bone defect healing. We selected 30 male weight equal rabbits and, in aseptic surgery, resected a 3-mm-thick piece of full-thickness of bone. Then we divided randomly them into two equal groups, the control, and the recipient. In the first, second, third, and sixth weeks of the radiographed bones were obtained. Also, in the third, sixth, and eighth weeks of each group, 5 rabbits were euthanized and their bones were histopathologically evaluated. Results from the second to sixth weeks of the study showed a significant difference between the treatment group and the control group. This difference was indicative of an increase in the rate of bone healing in the treatment group. Ozone therapy can therefore be considered effective in bone healing.

The aim of this study was to evaluate possible beneficial effect of tricalcium phosphate/collagen (TCP/collagene) nanocomposite scaffold on bone healing in rabbits using biochemical assessmentsDesign- Experimental studyAnimals- Twelve healthy male white New Zealand rabbits

The rabbits were marked with non-toxic color and randomly divided into two groups of 6 animals each. In the first group (SHAM) the defect was made and with no treatment the wound was closed. In the second group (TCP/C) the tricalcium phosphate/collagen (TCP/collagene) nanocomposite scaffold was implanted into the defect. Before the procedures (day 0) and on 7, 15, 30, 45 and 60 postoperative days the blood samples were taken from jugular vein and undergone hematological and biochemical assessments.

The hematological, biochemical and oxidative stress parameters including WBC, RBC, HCT, PLT, neutrophil, lymphocytes, BUN, Creatinine, AST, ALT, ALP, SOD, GPX and MDA showed statistically significant differences between Sham and TCP/C groups (p<0.05).   

It was concluded that TCP/collagen nanocomposite improved the biochemical parameters in the nanocomposite treated animals and could be of clinical benefit in reconstruction of bone defects and could be considered as a scaffold in bone fractures.

The aim of this study was to compare the efficacy of honey bee venom (BV) and royal jelly (RJ) alongside chitosan scaffold (CS) in improving radius bone defect in rats. A total of 60 full thickness radial bone defects with a length of 5 mm were created in 60 male Wistar rats. Six healthy radial bones (3 rats) were also assigned as normal control for biomechanical studies. The defects were left empty (untreated group) or were filled by the autograft (autograft group), CS (CS group), CS alongside the BV solution (CS-BV group), and CS alongside the RJ solution (CS-RJ group). Healing of the bone defects were evaluated clinically and radiologically on days 0, 28, 42 and 56 after operation while the biomechanical testing and histopathological examination were performed on the 56th day after surgery. The autograft was more radiopaque than the untreated and CS groups at the 28th, 42nd and 56th postoperative days (P<0.05). The CS-BV and CS-RJ groups showed significantly higher radiographic outcomes than the untreated and CS groups at the 56th post-operative day (P<0.05). The density of osseous tissue (DOT) and the osteocytes and osteoblasts count of the CS-RJ and CS-BV groups were significantly higher than the CS and autograft groups (P<0.05). The biomechanical results of the CS-RJ group were significantly superior to the autograft, while the biomechanical properties of CS-BV group were not significantly different with the autograft group (P>0.05). The scaffolds in CS group were observable in the surgical site after 56 days. There was no significant difference in radiographs, DOT, cartilage tissue and fibrous tissue, and also biomechanical performances of the CS-BV and CS-RJ groups at the 42nd and 56th day after surgery. The untreated and CS groups showed weakest biomechanical results among all groups. It could be concluded that both treatment strategies in the CS-BV and CS-RJ groups were appropriate and useful in treating critical bone defects.

Bone has a capability to repair itself when it is fractured. Repair involves the generation of intermediate tissues, such as fibrous connective tissue, cartilage and woven bone, before final bone healing can occur. The process of cartilage-to-bone transition (CBT) is a key for the achievement of rigid bone healing during fracture repair. We tested this potential for elastic cartilage using a long bone defect model in dog. Eight sexually intact female mongrel dogs, 4.57 ± 0.53 years old and weighing 11.48 ± 0.63 kg, were studied. After an ostectomy of the midshaft radius, bone healing was evaluated over an 8-week period in control dogs (n = 4) and dogs in which autologous grafts of auricular cartilage were inserted into the bone defects (n = 4). Quantitative radiographic assessment was conducted every 2 weeks. Eight weeks post-operative, qualitative histopathologic analysis was performed on the operated radii. Furthermore, histological grading was done using the Ulutas et al., scoring system. Experiment dogs had more advanced radiographic healing of ostectomy sites. The defects with elastic cartilage implants were bridged completely with new bony spicules originated from the implants. Transformation of elastic cartilage clusters to mesenchymal connective tissue and bony spicules was obvious in the experiment group. Significant differences were observed for cellular morphology [3 ± 0.82 (experiment) vs. 1.75 ± 0.5 (control)] and cartilage integration [2 (experiment) vs. 1 (control)] at ostectomy sites between the studied groups. This study demonstrated that by using the ostectomy gap model, autologous auricular cartilage enhanced the radiographic and histopathologic aspects of bone healing in dogs.