ObjectiveTo investigate the feasibility of tissue engineered periosteum (TEP) constructed by porcine small intestinal submucosa (SIS) and bone marrow mesenchymal stem cells (BMSCs) of rabbit to repair the large irregular bone defects in allogenic rabbits. MethodsThe BMSCs were cultivated from the bone marrow of New Zealand white rabbits (aged, 2 weeks-1 month). SIS was fabricated by porcine proximal jejunum. The TEP constructed by SIS scaffold and BMSCs was prepared in vitro. Eighteen 6-month-old New Zealand white rabbits whose scapula was incompletely resected to establish one side large irregular bone defects (3 cm×3 cm) model. The bone defects were repaired with TEP (experimental group,n=9) and SIS (control group,n=9), respectively. At 8 weeks after operation, the rabbits were sacrificed, and the implants were harvested. The general condition of the rabbits was observed; X-ray radiography and score according to Lane-Sandhu criteria, and histological examination (HE staining and Masson staining) were performed. ResultsAfter operation, all animals had normal behavior and diet; the incision healed normally. The X-ray results showed new bone formation with normal bone density in the defect area of experimental group; but no bone formation was observed in control group. The X-ray score was 6.67±0.32 in experimental group and was 0.32±0.04 in control group, showing significant difference (t=19.871,P=0.001). The general observation of the specimens showed bone healing at both ends of the defect, and the defect was filled by new bone in experimental group; no new bone formed in the control group. The histological staining showed new bone tissue where there were a lot of new vessels and medullary cavity, and no macrophages or lymphocytes infiltration was observed in the defect area of experimental group; only some connective tissue was found in the control group. ConclusionTEP constructed by porcine SIS and BMSCs of rabbit can form new bone in allogenic rabbit and has the feasibility to repair the large irregular bone defects.
Oral carcinoma；Platysma myocutaneous flap；Defect repair
Objective To investigate the effect of simvastatin on inducing endothel ial progenitor cells (EPCs) homing and promoting bone defect repair, and to explore the mechanism of local implanting simvastatin in promoting bone formation. Methods Simvastatin (50 mg) compounded with polylactic acid (PLA, 200 mg) or only PLA (200 mg) was dissolved in acetone (1 mL) to prepare implanted materials (Simvastatin-PLA material, PLA material). EPCs were harvested from bone marrow of 2 male rabbits and cultured with M199; after identified by immunohistochemistry, the cell suspension of EPCs at the 3rd generation (2 × 106 cells/mL) was prepared and transplanted into 12 female rabbits through auricular veins(2 mL). After 3 days, the models of cranial defect with 15 cm diameter were made in the 12 female rabbits. And the defects were repaired with Simvastatin-PLA materials (experimental group, n=6) and PLA materials (control group, n=6), respectively. The bone repair was observed after 8 weeks of operation by gross appearance, X-ray film, and histology; gelatin-ink perfusion and HE staining were used to show the new vessels formation in the defect. Fluorescence in situ hybridization (FISH) was performed to show the EPCs homing at the defect site. Results All experimental animals of 2 groups survived to the end of the experiment. After 8 weeks in experimental group, new bone formation was observed in the bone defect by gross and histology, and an irregular, hyperdense shadow by X-ray film; no similar changes were observed in control group. FISH showed that the male EPC containing Y chromosome was found in the wall of new vessels in the defect of experimental group, while no male EPC containing Y chromosome was found in control group. The percentage of new bone formation in defect area was 91.63% ± 4.07% in experimental group and 59.45% ± 5.43% in control group, showing significant difference (P lt; 0.05). Conclusion Simvastatin can promote bone defect repair, and its mechanism is probably associated with inducing EPCs homing and enhancing vasculogenesis.
Objective To investigate the expression levels and significance of vascular endothel ial growth factor (VEGF) and microvessel density (MVD) in rabbit radius defects repaired with allogeneic and autogenic bone. Methods Forty adult New Zealand rabbits were chosen, and 10 mm bone defect model was created in the bilateral radii of 28 experimental rabbits. The other 12 rabbits provided allogeneic bone under the standard of American Association of Tissue Bank. In the left side, allogeneic bone were used to repair bone defect (experimental group), equal capacity autogenous il iac bone was used in the right side (control group). Animals were sacrificed at 2, 4, 8, and 12 weeks postoperatively. Immunohistochemical method was used to determine the expression of VEGF, CD34 protein and MVD counting. Bone histomorphometric parameters, including percent trabecular area (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp) were measured by von Kossa staining undecalcified sl ices. The relation was analyzed between VEGF and MVD, histomorphometric parameters. Results The positive signals of VEGF protein were detected in cytoplasm of vascular endothel ial cells, chondrocytes, osteoblasts, fibroblasts and osteoclasts. At 2 weeks, there was no significant difference in VEGF protein expression between experimental group and control group (P gt; 0.05); at 4 and 8 weeks, the expression of VEGF in control group was significantly higher than that in experimental group (P lt; 0.05); and at 12 weeks, there was no significant difference between two groups (P gt; 0.05). There was a positive correlation (P lt; 0.01) between VEGF expression and MVD value in two groups at 2, 4, 8, and 12 weeks postoperatively. There was no significant difference in bone histomorphometric parameters (BV/TV, Tb.Th, Tb.N, Tb.Sp) between two groups at 12 weeks postoperatively (P gt; 0.05), but there was a positive correlation between VEGF expression and parameters of BV/TV, Tb.Th, and Tb.N (P lt; 0.01); and a negative correlation between VEGF and Tb.Sp (P lt; 0.01). Conclusion VEGF can express diversity at different time and positions, and the different expressions indicated various biology significances in the process of the bone heal ing. It can coordinate growth of cartilage and bone and profit vascular reconstruction of allogeneic bone. VEGF may participate in promoting osteogenesis in the course of allogeneic bone transplantation.
ObjectiveTo explore the reliability and effectiveness of soft tissue defect reconstruction using the lower trapezius musculocutaneous flap carrying a portion of the latissimus dorsi muscle.MethodsBetween December 2014 and December 2019, 13 patients underwent the reconstruction of soft tissue defects in various sites using the lower trapezius musculocutaneous flap carrying a portion of the latissimus dorsi muscle. There were 10 males and 3 females, with an average age of 52.1 years (range, 29-83 years). Twelve wounds were resulted from resection of various malignant tumor, including 6 cases of head and neck tumors, 5 cases of shoulder and back tumors, 1 case of chest and back tumors. Among the 12 cases, 4 cases were complicated with wound infection and bone exposure, 1 case with skull defect and cerebral dura exposure, and 1 case with wound infection, skull necrosis, and cerebrospinal fluid leakage. One case was injured in a traffic accident, which resulted in infection wound in the back and shoulder and bone exposure. The sizes of the defect and musculocutaneous flap ranged from 11 cm×7 cm to 23 cm×15 cm and 25 cm×8 cm to 40 cm×14 cm, respectively. According to the spatial relationship between the donor and recipient sites, propeller flaps (8 cases) or percutaneous tunnel island flaps (5 cases) were used to transfer the myocutaneous flap to the recipient area to repair the wound. The donor site was directly closed and sutured in 9 cases, and those with excessive tension were repaired with free skin grafts in 2 cases or transferred flaps in 2 cases.ResultsAfter the operation, necrosis of the distal 4-cm of the musculocutaneous flap occurred in 2 cases. After debridement, the resultant wounds were reconstructed using a local flap and a posterior intercostal artery perforator flap, respectively. The remaining 11 myocutaneous flaps survived completely without arteries and veins crisis. The wounds in the donor and recipient areas healed by first intention. All the patients were followed up 1 to 48 months (mean, 7.4 months). The color and texture of the flap were good. During the follow-up, 1 patient underwent tumor resection again due to tumor recurrence, and 1 patient with a scalp hemangiosarcoma died due to unexplained thoracic hemorrhage. Tumor recurrence was not found in the remaining patients. The musculocutaneous flap coverage was stable and the infection was controlled.ConclusionThe lower trapezius musculocutaneous flap carrying a portion of the latissimus dorsi muscle can be an alternation option to reconstruct refractory wounds with exposure of vital structures and organs and infection.
ObjectiveTo investigate the application of three-dimensional (3-D) printing technique combining with 3-D CT and computer aided-design technique in customized artificial bone fabrication, correcting mandibular asymmetry deformity after mandibular angle ostectomy. MethodsBetween April 2011 and June 2013, 23 female patients with mandibular asymmetry deformity after mandibular angle ostectomy were treated. The mean age was 27 years (range, 22-34 years). The disease duration of mandibular asymmetry deformity was 6-16 months (mean, 12 months). According to the CT data and individualized mandibular angle was simulated based on mirror theory, 3-D printed implants were fabricated as the standard reference for manufacturers to fabricated artificial bone graft, and then mandible repair operation was performed utilizing the customized artificial bone to improve mandibular asymmetry. ResultsThe operation time varied from 40 to 60 minutes (mean, 50 minutes). Primary healing of incisions was obtained in all patients; no infection, hematoma, and difficulty in opening mouth occurred. All 23 patients were followed up 3-10 months (mean, 6.7 months). After operation, all patients obtained satisfactory facial and mandibular symmetry. 3-D CT reconstructive examination results after 3 months of operation showed good integration of the artificial bone. Conclusion3-D printing technique combined with 3-D CT and computer aided design technique can be a viable alternative to the approach of maxillofacial defects repair after mandibular angle ostectomy, which provides a accurate and easy way.
Aiming at the problem of scaffold degradation in bone tissue engineering, we studied the feasibility that controlls bone defect repair effect with the inhomogeneous structure of scaffold. The prediction model of bone defect repair which contains governing equations for bone formation and scaffold degradation was constructed on the basis of analyzing the process and main influence factors of bone repair in bone tissue engineering. The process of bone defect repair and bone structure after repairing can be predicted by combining the model with finite element method (FEM). Bone defect repair effects with homogenous and inhomogeneous scaffold were simulated respectively by using the above method. The simulation results illustrated that repair effect could be impacted by scaffold structure obviously and it can also be controlled via the inhomogeneous structure of scaffold with some feasibility.
【Abstract】 Objective To investigate the effectiveness of the medical calcium sulfate—OsteoSet bone graft substitute in the treatment of defect after excision of jaw cyst. Methods Between December 2009 and May 2010, 15 cases of jaw cystic lesion were treated，including 9 males and 6 females with an average age of 36.6 years (range, 15-75 years). Orthopantomography (OPT) method was used to measure the cyst size before operation, and the size ranged from 1.5 cm × 1.5 cm to 8.0 cm × 3.0 cm. The range of bone defect was from 1.5 cm × 1.5 cm × 1.5 cm to 8.0 cm × 3.0 cm × 3.0 cm after cyst excision intraoperatively. The patients underwent cyst curettage and OsteoSet bone graft substitutes implantation (2-15 mL). Radiological method was used to evaluate the repair effect of OsteoSet pellets. Results The pathology biopsy was periapical cyst in 7 cases, odontogenic keratocyst in 5 cases, and dentigerous cyst in 3 cases. Fifteen patients were followed up 6-12 months. Thirteen patients achieved wound healing by first intention; 2 cases had longer drainage time (5 and 7 days, respectively), the incision healed after the pressure bandage. Swelling occurred in 1 case after 1 month with no symptom of infection. No postoperative infection and rejection was found. The X-ray examination showed that the materials filled the bone defect well after 1 day of operation. OsteoSet bone graft substitutes were absorbed by one-half after 1 month of operation and totally after 3 months by OPT. The low density area was smaller in the original cysts cavity, and high density in the cysts increased significantly with fuzzy boundaries of cysts. At 6 months after operation， there was no obvious difference in image density between the original cavity and normal bone, and the capsule cavity boundary disappeared, and defect area was full of new bone. Conclusion The medical calcium sulfate—OsteoSet bone graft substitute is an ideal filling material for bone defect.
目的 探讨对Mirizzi综合征实施临床合理有效的手术方法。方法 自1990年1月至2003年12月期间，我院采用经肝放置胆道支撑引流管治疗Ⅱ、Ⅲ型Mirizzi综合征21例,胆道支撑引流管放置6个月以上，并行胆道造影检查。结果 所有患者恢复良好,胆道造影检查见胆道通畅后拔除支撑引流管，随访2～10年,无并发症发生。结论 经肝放置胆道支撑引流管治疗Ⅱ、Ⅲ型Mirizzi综合征,是保持胆道生理功能完整的有效方法。