Objective To evaluate the bone regenerative potential of reconbinant human bone morphogenetic protein 2(rhBMP-2) / collagen on adult rat calvarial bone. Methods A tight subperiosteal pocket was produced under both sides ofthe temporal muscle in rats. rhBMP-2 / collagen was implanted in one side and collagen alone was implanted in the other side as control. The rats were sacrificed 2, 4 and 8 weeks after operation. The specimen was harvested and examined histologically. For morphometric analysis, the thickness of the temporal bone of both sides was measured and compared. Results The rhBMP-2 / collagen onlay implant resulted in active bone formation and the augmented bone was connected directly with the original bone, whereas the collagen alone resulted in neither bone nor cartilage production. The ossification process in the rhBMP-2 / collagen occurred directly through bone formation, similar to intramembranous ossification. Conclusion rhBMP-2 / collagen is an effective material as a biological onlay implant.
ObjectiveTo compare the clinical outcomes of transcatheter aortic valve implantation (TAVI) in oncology and non-oncology patients with severe aortic stenosis (AS).MethodsA computer-based search in PubMed, The Cochrane Library, EMbase, CBM, CNKI and Wanfang databases from their date of inception to December 2021 was performed, together with reference screening, to identify eligible clinical trials. Two investigators screened the articles, extracted data, and evaluated quality independently. RevMan 5.3 and Stata 12.0 softwares were used for meta-analysis.ResultsThe selected 8 cohort studies contained 57 988 patients, including 12 335 cancer patients and 45 653 non-cancer patients. The results of meta-analysis showed that in patients with cancer, the 30-day mortality [OR=0.74, 95%CI (0.65, 0.84), I2=0%, P<0.000 01], stroke [OR=0.87, 95%CI (0.76, 0.99), I2=0%, P=0.04] and acute kidney injury [OR=0.81, 95%CI (0.76, 0.85), I2=49%, P<0.000 01] were lower than those in patients without cancer. The 1-year mortality [OR=1.46, 95%CI (1.15, 1.86), I2=62%, P=0.002] and late mortality [OR=1.51, 95%CI (1.24, 1.85), I2=61%, P<0.000 1] were higher in patients with cancer.ConclusionIt is effective and safe in cancer patients with severe AS undergoing TAVI. However, compared with patients without cancer, it is still high in long-term mortality, and further study of the role of TAVI in cancer patients with AS is necessary.
OBJECTIVE: To construct tissue engineering bone with bio-derived materials and bone marrow stromal cells (MSCs), and to investigate the effect of allogeneic engineering bone implants on healing of segmental bone defects. METHODS: MSCs being aspirated aseptically from tibial tuberosities of young rhesus monkeys were induced into osteoblasts in vitro and then were cultured and marked with 5-bromo-2-deoxyuridine (BrdU). Tissue engineering bones were constructed with these labeled osteoblasts being seeded onto bio-derived materials made from fresh human bones which were treated physically and chemically, Then the constructs were implanted in 15 allogeneic monkeys to bridge 2.5 cm segmental bone defects of left radius as experimental groups, bio-derived materials only were implanted to bridge same size defects of right radius as control group. and, 2.5 cm segmental bone defects of both sides of radius were left empty in two rhesus monkeys as blank group. Every 3 monkeys were sacrificed in the 1st, 2nd, 3rd, 6th and 12th weeks postoperatively and both sides of the implants samples were examined macroscopically, histologicaly, and immunohistochemicaly. The two monkeys in blank group were sacrificed in the 12th week postoperatively. RESULTS: Apparent inflammatory reactions were seen around both sides of the implants samples in the 1st, 2nd, 3rd weeks, but it weakened in the 6th week and disappeared at the 12th week. The labeled osteoblasts existed at the 6th week but disappeared at the 12th week. The bone defects in experimental group were repaired and the new bone formed in multipoint way, and osteoid tissue, cartilage, woven bone and lamellar bone occurred earlier when compared with control group in which the bone defects were repaired in ’creep substitution’ way. The bone defects in blank group remained same size at the 12th week. CONCLUSIONS: Engineering bones constructed with bio-derived materials and MSCs were capable of repairing segmental bone defects in allogeneic monkeys beyond ’creep substitution’ way and making it healed earlier. Bio-derived materials being constituted with allogeneic MSCs may be a good option in construction of bone tissue engineering.
Since November 1996, 20 cases of craniofacial deformities, either from congenital or traumatic, were treated with MEDPOR surgical implant made from a linear high density polythylene. The animal experiment had shown that the MEDPOR had good organotrophic characteristics allowing tissue ingrowth. The biocompatibility studies in vitro and in vivo had shown that the MEDPOR biomaterial was free from any observable systemic or cytotoxic effect. In the clinical application, it was found that the MEDPOR could be easily modeled and maintained. Because of the ability to induce tissuee ingrowth, the tenacity and stability of the material were enhanced. A total of seven cases of cranial defects, 8 cases of periobital defects or depressed periobital regions, 2 cases of traumatic auricular defects, 2 cases of traumatic saddle nose and 1 case of maldevelopment of mandible angle were treated. All of the cases were followed up for 6 months, the results were satisfactory.
ObjectiveTo observe the morphological characteristic by implanting domestic porous tantalum in rabbit patellar tendon and to evaluate biocompatibility features so as to provide experimental basis for porous tantalum used as interface fixation between tendon and bone. MethodsA total of 48 adult New Zealand white rabbits, male or female, weighing 2.5-3.0 kg, were selected. Porous tantalum flake (5 mm×5 mm×2 mm) was implanted in the left patellar tendon (experimental group) and the same size porous titanium flake in the right patellar tendon (control group). The animals were sacrificed at 2, 4, 8, and 12 weeks after implantation, then the specimens were harvested for gross observation, HE staining, scanning electron microscope (SEM) observation, and hard slices observation. ResultsNo animal died after operation. Porous tantalum was bonded closely with host tendon and no inflammatory reaction was found. Loose and thick fibrous capsule was observed at the beginning and became density and thinner in the end by microscope, showing significant difference between different time points in 2 groups (P<0.05), but no significant difference was found between 2 groups at different time points (P>0.05). The SEM observation showed that fibrous tissue attached to the surface and inner walls of porous tantalum at early stage, and extended on the material to reach confluence at late period, but the experimental group was more than the control group. Hard slices observation showed that the collagen fibrils were seen on porous tantalum interface with host tendon, and blood vessels grew into the pores. The control group and the experimental group showed no significant difference. ConclusionThe domestic porous tantalum has good biocompatibility. Connection and integration can be established between tendon and porous tantalum, and therefore it could be used in reconstruction of tendon-bone fixation device.
ObjectiveTo explore surgical methods and risk factors of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). MethodsClinical data of 28 ALCAPA patients who underwent surgical repair from October 1993 to September 2013 in Beijing Anzhen Hospital were retrospectively reviewed. There were 8 male and 20 female patients with their age of 0.6-l6.8 (4.3±0.7)years including 10 patients less than 1 years old. Surgical procedures included simple ligation of left coronary artery, intrapulmonary tunnel procedure (Takeuchi)and direct coronary reimplantation of the anomalous artery. Postoperative death, complication and cardiac function were observed. ResultsAmong the 28 patients, 1 patient received simple ligation of left coronary artery, and 7 patients received intrapulmonary tunnel procedure (Takeuchi), among whom 2 patients died postoperatively. Twenty patients received direct implantation of the anomalous artery into the ascending aorta, and 3 patients died postoperatively. Five patients who died postoperatively were 10.20±3.27 months old, including 3 patients with moderate mitral regurgitation (MR)and 2 patients with mild MR preoperatively. Preoperative heart function of the patients who died postoperatively was significantly reduced. Preoperative left ventricular ejection fraction of the patients who died postoperatively was significantly lower than that of the patients who survived (36.6%±8.5% vs. 60.9%±10.7%, P=0.000). Low cardiac output syndrome was the reason for all postoperative death. All survival patients were followed up from 1 month to 18 years. One patient who underwent intra-pulmonary tunnel procedure (Takeuchi)received pulmonary artery balloon dilatation for pulmonary supravalvular stenosis 15 years after discharge. None of the other patients received a secondary operation. During follow-up, left ventricular function was improved. Growth and development of all the patients was normal. MR did not significantly aggravate in all the patients. ConclusionPatients with younger age and worse left ventricular function have greater surgical risks of ALCAPA.
Objective To evaluate clinical outcomes, patient satisfaction, and maintenance after treatment from mandibular implant-supported overdentures with different attachment types. Methods We searched six electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 4, 2005), Current Controlled Trials, MEDLINE (1966 to Sept. 2005), EMBASE (1984 to Sept. 2005), and Chinese biomedical database disk (1978 to Sept. 2005). Eleven Chinese professional journals in oral health were also handsearched from their first published issues. Three authors screened and selected the studies, appraised their methodological quality and extracted data from the studies. The results were presented narratively by meta-analysis. Results After strict screening, 12 trials involving 282 patients were included. Two of the trials were included in a meta-analysis with 27 patients in bar-clip group, 29 patients in ball-spring group, and the other trials were described thoroughly. The findings seemed to indicate that the bar-clip group had the highest retention but more oral mucosa complications, while the ball-spring group had good retention and less oral mucosa complications but needed more aftercare treatments, and the magnetic group had less retention but better peri-implant outcomes. Conclusions There is inadequate evidence to prove which is the best choice for mandibular implant-supported overdentures among bar-clip, ball-spring and magnetic attachments. More controlled clinical trials are required to guide clinicians on the choice of the type of attachment in mandibular implant-supported overdenture.
To evaluate the effect of technique combination of implant-retented titanium lattice with decalcified dental matrix (DDM) implanting. Methods Six healthy male dogs (weighing of 10-20 kg) were randomly divided into 3 groups. All the premolars were extracted on both sides of the jaw in dogs. After 2 weeks, titanium lattice and implant were implanted in the maxillary premolar region with DDM on one side (experimental group), but without on the other side (control group) of each dog. After 4, 9 and 14 weeks, respectively, 2 animals were individually killed each time, and the samples wereevaluated by general observation, X-ray examination, histological observation and histomorphometric analyses. Results General observation: Among the 6 dogs, there was no postoperative infection or death. The X-ray examination showed that the bone density of the experimental group was greater than the control group at 4 and 9 weeks, and had no significant difference as to the vicinity bone at 14 weeks. On the other hand, the density of the control group was very low under the titanium lattice and around the implant. The experimental group revealed a ridge augment of (1.93 ± 0.24) mm, and control group (-1.02 ± 1.20) mm (P lt; 0.05). Developed bone sponge could be found after 14 weeks. Histological observation showed that in the experimental group, the DDM surface was nearly absorbed at 4 weeks. A few new bones were formed at 9 weeks. The whole DDM was absorbed; the trabecular bone was thick and arranged regularly; and the intergradations of implant were observed at 14 weeks. In the control group, there were some inflammatory fibers around the neck of implant at 4 weeks. The inflammatory condition extended to the root of implant and the titanium lattice at 9 weeks. There was no newly-formed bone under the titanium lattice at 14 weeks. Histomorphometric analyses showed that the implant contact bone ratio approached 1 ∶ 1, and showed no significant difference between the new bone fragment and former bone fragment in the experimental group. Conclusion This augmentation of alveolar ridge evaluated by the study is appl icable, but further study is necessary.
OBJECTIVE: To investigate an effective technique of temporary ectopic implantation for amputated extremity under complex condition. METHODS: Two cases of amputated foot, which could not be implanted primarily, were treated with temporary ectopic implantation. The other leg of patient was chosen as recipient site. The posterotibial artery and saphenous vein were chosen as recipient vessels. When the general condition and the proximal condition of the amputated part were suitable, the ectopic implanted feet were transferred to their anatomic positions. RESULTS: All the feet survived after the replantation. The injured limbs recovered their normal length and sensation. The patients could walk after 4-6 months. CONCLUSION: Temporary ectopic implantation is an ideal technique for the salvage of amputated limb and organ under special condition. Severed foot and lower segment of the leg under complex condition were the best indication for the temporary ectopic implantation.
Because of its high biological compatibility, titanium has been a good biomaterial. The implanted artificial bone made from titanium can contact with the vital and mature osseous tissue directly within 3-6 months, the so-called osteointergration. In order to promote the process of osteointergration, FDBM of rabbit was prepared and was combined with pure titanium so as to speed up osteointergration. The study focused on bone density, bone intergration rate, new bone growth rate around the pure titanium, and the Ca2+ and PO(4)3- density of titanium-bone interface. A control group of pure titanium inplant without FDBM was set up. The results showed FDBM had no antigenicity. It could induce and speed up the new bone formation at titanium-bone interface. The titanium-bone intergration time was within 2 months. It was suggested that there were more bone morphogenesis protein (BMP) or other bone induction and bone formation factors in brephobone than that in child and adult bone. As a kind of bone induction material, FDBM was easy prepared, cheap in price, easy to storage, no antigenicity and obvious bone-inductive function.