Objective To compare and evaluate the capability of pure autogenous bone and the enhanced autogenous bone combined with bone morphogenetic protein in bone repair of femoral head. Methods Eighteen femoral heads of 9 dogs weredrilled by trephine, 4 mm in diameter, followed by respective implantations of autogenous bone grafting (group B) and of the enhanced autogenous bone composite, combined with bone morphogenetic protein (group C), with the selfrepair of bone defect as the control (group A). Three, six, nine weeks after the operation, radiological examination, computerized tomography, light and electronic microscopes were performed to investigate the bone healing of the defect in the femoral head. Results In group A, it could be observed that there washematoma organization and delayed woven bone formation in the 3rd week after operation, and therewas little replacement of woven bone by bone trabecula in the 9th week; in group B, the autogenous bone implanted were dead in the 3rd week and maintained in situ in the 9th week; in group C, active new bone formation, either endochondral or intramembranous ossification, was found in the 3rd week and entire repair of the bone defect by bone trabecula in the 9th week after operation. Conclusion The enhanced autogenous bone combined with bone morphogenetic protein could promote reconstruction of the bone defect in femoral head, superior to pure autogenous bone which could provide a framework for the new bone formation.
It is in urgent need clinically to look for an ideal substance for the coverage of burn wounds owing to shortage of autografts or allografts. After the cadaveric skin was extracted with acetic acid, salted out with NaCl and freeze-dried to prepare a porous collagen membrane. The membrane was seeded with allo-epidermal cells and allo-fibroblasts on its two sides, respectively, and then was cultured to achieve an artificial composite allograft. The artificial composite allograft was then transplanted onto ten severly burned wounds. One-year follow-up showed satisfactory results and the histological examination confirmed that the composite allograft could improve the adherence and growth of the epidermal cells and was helpful for blood vessels and healing of non-inflammatory connective tissues in the wounds.
ObjectiveTo explore a new improved technique and its effectiveness to repair dorsal thumb composite tissue defects including interphalangeal joint by transplantation of modified hallux toe-nail composite tissue flap. MethodsThe hallux toe-nail composite tissue flap carrying distal half hallux proximal phalanx, extensor hallucis longus, and interphalangeal joint capsule were designed and applied to repair the dorsal skin, nails, and interphalangeal joint defect of thumb in 14 cases between January 2007 and June 2013. They were all males, aged from 19 to 52 years (mean, 30 years). The time from injury to hospital was 0.5-2.0 hours (mean, 1.2 hours). The area of the thumb nail and dorsal skin defects ranged from 2.5 cm×1.5 cm to 5.0 cm×2.5 cm. The dorsal interphalangeal joint had different degrees of bone defect, with residual bone and joint capsule at the palm side. The length of bone defect ranged from 2.5 to 4.0 cm (mean, 3.4 cm). The hallux nail flap size ranged from 3.0 cm×2.0 cm to 6.0 cm×3.0 cm. The donor sites were repaired by skin grafting in 5 cases, and retrograde second dorsal metatarsal artery island flap in 9 cases. ResultsAfter operation, arterial crisis occurred in 1 case and the flap survived after relieving pressure; the other flaps survived, and wounds healed by first intention. Liquefaction necrosis of the skin grafting at donor site occurred in 3 cases, and the other skin grafting and all retrograde second dorsal metatarsal artery island flaps survived. The follow-up ranged from 9 months to 3 years and 6 months (mean, 23 months). The secondary plastic operation was performed in 4 cases at 6 months after operation because of slightly bulky composite tissue flaps. The other composite tissue flaps had good appearance, color, and texture. The growth of the nail was good in 12 cases, and slightly thickened in 2 cases. At last follow-up, X-ray examination showed that bone graft and proximal phalanx of the thumb had good bone healing in 12 cases. Good bone healing was obtained at the donor site. According to the Hand Surgical Branch of Chinese Medical Association standard for thumb and finger reconstruction function, the results were excellent in 12 cases and good in 2 cases, and the excellent and good rate was 100%. No pain at donor site was observed, with normal gait. ConclusionTransplantation of modified hallux toe-nail composite tissue flap to repair dorsal thumb composite tissue defects including interphalangeal joint can effectively improve the appearance and function of the impaired thumb.
Objective To investigate a new grafting material of bone xenograft with b bone inductive and conductive capacity. Methods Based on successful clinical application of the reconstituted bone xenograft (RBX), a new xenograft was made by combining recombinant human bone morphogenetic protein-2 (rhBMP-2) with antigen-free bovine cancellous bone (BCB). Sixty male BALB/C mice aged 4 weeks were divided into study group of 30 and control group of 30 randomly. rhBMP-2 / BCB was implanted in the left thigh muscle pouch in the study group andBCB in the control group. The mice were sacrificed at 7 d, 14d and 21d after implantation. Inductivity of rhBMP-2/BCB was detected by histological observation and biochemical determination of the samples. Results Histological examinationshowed that rhBMP-2/BCB induced chondrogenesis on the 7th day, with woven boneformed on the 14th day, and lamellar bone and marrow on the 21st day, while BCBfailed to induce chondrogenesis or osteogenesis on the 7th, 14th and 21st days. The alkaline phosphatase activities and calcium content in study group were higher than those in control group with significant difference (P＜0.01). Conclusion rhBMP-2/BCB is an ideal grafting material with b bone inductive and conductive capacity without evoking immune reaction.
Objective To assess the clinical outcome of thelimb salvage surgery and complications occurring in the lower extremities after a wide resection of sarcoma. 〖WTHZ〗Methods A total of 167 patients underwent a limb-sparing procedure by means of the implantation of a custom-made or modular tumor endoprosthesis from July 1997 to July 2004. Of the 167 patients, 100 were followed up, including 56 males and 44 females, with their ages ranging from 13 to 57 years at surgery.In 5 patients, a proximal femur prosthesis was implanted; in 57 patients, a distal femur prosthesis was implanted; and in 38 patients, a proximal tibia prosthesis was implanted. According to the Enneking staging, 3 patients were grouped in the stage of ⅡA, 85 in ⅡB, and 12 in Ⅲ. Seventy-one patients used a domestic prosthesis, and 29 patients used a prosthesis made in Link Company, Germany. For the reconstruction, 17 patients used an autograft prosthesis composite, 21 patients used the allograft prosthesis composite, and the remaining 62 patients used an artificial prosthesis. All the patients received chemotherapy for 1-2 courses and 3-5 courses before operation and after operation, respectively. After operation, The Musculoskeletal Tumor Society(MSTS) score was used to evaluate the recovery of their corresponding functions. Results According to the follow-up for 1-8 years, with a median of 3.5 years, and the assessment by the Kaplan-Meier estimate, the 3-year survival rate of the prostheses was 81.8%, and the 5year survival rate was 65%. As for the complications, prosthesis breakage occurred in 6 patients, periprosthesis infection in 13 patients, aseptic loosening in 2 patients, non-union between the host bone and graft bone in 5 patients, allograft absorption in 2 patients, prosthesis sinking in 2 patient, and periprosthesis fracture in 1 patient. Local recurrence developed in 7 patients within 6 months to 2 years after operation. Of the 7 patients, 4 had a recurrence of the softtissue tumor for which resection was performed; the other 3 patients underwent amputation of the diseased limb. The mean MSTS score was 23.30±5.17, with an excellent limb function in 62 patients, good in 27 patients, fair in 7 patients, and poor in 4 patients. The overall excellent and good function was obtained in 89% of the patients. Conclusion We conclude that tumor prostheses can give a satisfactory functional outcome after the tumor around the knee is removed; however, the tumor prostheses still need to be further improved because of a high complication rate.
OBJECTIVE: To observe the clinical effect of acellular allogenic dermis with split-thickness autogenous skin graft for coverage of wound. METHODS: Acellular allogenic dermis with split-thickness autogenous skin graft was used to repair 34 wounds of head, neck, trunk and extremities. The area of wounds was from 5 cm x 10 cm to 12 cm x 19 cm. Out of 34 wounds, there were 2 due to old granulation, 4 due to excision of giant pigmented nevus, 6 due to excision of capillary hemangioma of skin and 22 due to excision of scar. RESULTS: All grafts survived and had the smooth surface without obvious pigmentation and with slight wound contraction. CONCLUSION: Acellular allogenic dermis with autologous epithelium for coverage of various wounds is an ideal procedure.
The stiffness of an ideal fracture internal fixation implant should have a time-varying performance, so that the fracture can generate reasonable mechanical stimulation at different healing stages, and biodegradable materials meet this performance. A topology optimization design method for composite structures of fracture internal fixation implants with time-varying stiffness is proposed, considering the time-dependent degradation process of materials. Using relative density and degradation residual rate to describe the distribution and degradation state of two materials with different degradation rates and elastic modulus, a coupled mathematical model of degradation simulation mechanical analysis was established. Biomaterial composite structures were designed based on variable density method to exhibit time-varying stiffness characteristics. Taking the bone plate used for the treatment of tibial fractures as an example, a composite structure bone plate with time-varying stiffness characteristics was designed using the proposed method. The optimization results showed that material 1 with high stiffness formed a columnar support structure, while material 2 with low stiffness was distributed at the degradation boundary and inside. Using a bone remodeling simulation model, the optimized bone plates were evaluated. After 11 months of remodeling, the average elastic modulus of callus using degradable time-varying stiffness plates, titanium alloy plates, and stainless steel plates were 8 634 MPa, 8 521 MPa, and 8 412 MPa, respectively, indicating that the use of degradable time-varying stiffness plates would result in better remodeling effects on the callus.
Objective To evaluate midterm and longterm clinical outcome of bilateral internal mammary artery composited Y grafts for coronary artery bypass grafting (CABG)， analyze risk factors for late death ，and to improve surgical results. Methods Between January 2000 and May 2004, One hundred and sixtyfive patients underwent bilateral internal mammary artery grafts for CABG, The clinical data, postoperative complications and survival results were retrospectively reviewed and analyzed. The preoperative and postoperative cardiac function was compared. All factors that may have affected the survival were analyzed by logistic regression, to identify significant variables associated with late death. Results Total 561 anastomosis sites of internal mammary arteries were completed with each patient received an average of 3.4 grafts. There were no perioperative deaths. There were 16 patients with postoperative complications including recurrent angina, myocardial infarction, low cardiac output syndrome, sternal infection and so on. All patients were treated conservatively without reoperation. One hundred sixty patients（97%）were followed up of 5.6±1.2 years, there were 23 late deaths including 10 patients of cardiac related death in which 3 had recurrent myocardial infarction, 4 heart failure, and 3 arrhythmia; 13 patients of nocardiac related death in which 4 upper gastrointestinal hemorrhage, 3 cancer and 6 uncertain cause. 25 patients had major cardiac related events including recurrent angina 18, myocardial infarction 4, repeated revascularization 3. Left ventricular ejection fraction [CM(159mm]was significantly improved as compared with that before operation（54%±6% vs. 43%±12%, Plt;0.05）. The 1-, 3-, 5-year actuarial survival rates and eventfree rates were 98.2%±0.3%, 96.2%±0.5%, 90.5%±1.9% and 95.5%±1.2%, 91.3%±2.1%, 86.6%±1.5%, respectively. According to statistical analysis, univariate analyses had proved that advancing age＞65 years，diabetes，ejection fraction(EF) less than 30%，the New York Heart Association (NYHA) class Ⅲ/Ⅳ, and low cardiac output syndrome required placement of the intraaortic balloon pump were predictors associated with hospital major adverse cardiac events (Plt;0.05). Those variables entered into the logistic regression model and found to be independent predictors associated with increased late cardiac death included advancing age ＞65 years(OR=11.6), diabetes (OR=21.4), EF less than 30%(OR=37.5) and NYHA class Ⅲ/Ⅳ(OR=40.2). Conclusion Patients receiving bilateral internal mammary artery composited Y grafts have better longterm survival and reduced cardiac related events. Independent risk factors for late death are NYHA function class Ⅲ/Ⅳ, EF less than 30%, diabetes and advancing age ＞65 years.
Objective To study cl inical effects of the graft material of allogenic cancellus combined with autologousred marrow in the treatment of traumatic bone defect. Methods From February 2002 to April 2006, 38 patients of traumaticbone defect, 25 males and 13 females, aged 21-68 years old (38 on average), were treated with allogenic cancellus combined with autologous red marrow. Among them, there were 11 cases of bone nonunion caused by failure of internal fixation, 13 of serious comminuted fracture, 9 of bone defect caused by open fractures or bone infection, 5 of old fracture in need of graft. Of these fractures, there were 8 cases of shaft of humerus, 4 of intercondylar comminuted fracture of humerus, 8 of intercondylar comminuted fracture of femur, 5 of shaft of femur, 4 of open tibia fracture (Gustilo I, II type) and 9 of tibial plateau fracture. They included 17 cases of fresh fracture and 21 of old fracture. There were 23 cases of l imitations of bone defect, and the range was 3 cm × 3 cm × 2 cm - 7 cm × 4 cm × 3 cm; and the range of the large bone defect was less than 3 cm in 15 cases. According to AO/ASIF classification, there were 5 cases of type B2, 10 of type B3, 16 of type C2 and 7 of type C3. The time from fresh fracture to operation was 5-17 days (8 days on average), and the time from old fracture to operation was 5-13 months (7.5 months on average). The amount of the allograft implantation was 20-50 g (28 g on average). Results The wounds in all 38 cases obtained heal ing by first intention. All the patients were followed up for 8 months to 4 years (3.2 years on average). The X-ray films at reexamination showed that 36 patients had bone heal ing, with fresh fracture heal ing time of 2-6 months (4 months on average) and old fracture heal ing time of 3-10 months (7 months on average). The allogenic cancellus particles began to be fused with autogenous bone through creeping substitution 6-8 weeks after operation. One case, which had delayed infection, had bone union by removing internal fixation, placing irrigating tube and grafting after local stabil ity. During the follow-up of 25 months, no relapse was found. Another case had nonunion because of plate loosening. According to the Mankin and Komender standard evaluation, there were 36 cases with satisfaction (94.7%) and 2 with dissatisfaction (5.3%). Conclusion The composite graft material of allogenic cancellus combined with autologous red marrow is safe and effective for repairing fractures and bone defect.
The poor mechanical property and vulnerability to bacterial infections are the main problems in clinic for dental restoration resins. Based on this problem, the purpose of this study is to synthesize silver-titanium dioxide (Ag-TiO2) nanoparticles with good photocatalytic properties, and add them to the composite resin to improve the mechanical properties and photocatalytic antibacterial capability of the resin. The microstructure and chemical composition of Ag-TiO2 nanoparticles and composite resins were characterized. The results indicated that Ag existed in both metallic and silver oxide state in the Ag-TiO2, and Ag-TiO2 nanoparticles were uniformly dispersed in the resins. The results of mechanical experiments suggested that the mechanical properties of the composite resin were significantly improved due to the incorporation of Ag-TiO2 nanoparticles. The antibacterial results indicated that the Ag-TiO2 nanoparticle-filled composite resins exhibited excellent antibacterial activities under 660 nm light irradiation for 10 min due to the photocatalysis, and the Ag-TiO2 nanoparticle-filled composite resins could also exhibit excellent antibacterial activities after contact with bacteria for 24 h without light irradiation because of the release of Ag ions. In summary, this study provides a new antibacterial idea for the field of dental composite resins.