The rutile structure titanium oxide (Ti-O) film was prepared on the pure titanium material TA2 (99.999%) surface by the magnetic filter high vacuum arc deposition sputtering source. The method can not only maintain the material mechanical properties, but also improve the surface properties for better biocompatibility to accommodate the physiological environment. The preparation process of the Ti-O film was as follows. Firstly, argon ions sputtered to the TA2 substrate surface to remove the excess impurities. Secondly, a metal ion source generated Ti ions and oxygen ions by the RF discharge. Meanwhile a certain negative bias was imposed on the sample. There a certain composition of Ti-O film was obtained under a certain pressure of oxygen in the vacuum chamber. Finally, X-ray diffraction was used to research the structure and composition of the film. The results showed that the Ti-O film of the rutile crystal structure was formed under the 0.18 Pa oxygen partial pressure. A Nano scratch experiment was used to test the coating adhesion property, which demonstrated that the film was stable and durable. The contact angle experiment and the platelet clotting experiment proved that the modified surface method had improved platelet adhesion performance, and, therefore, the material possessed better biocompatibility. On the whole, the evaluations proved the modified material had excellent performance.
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.
ObjectiveTo investigate the technique and the effectiveness of digital three-dimensional (3-D) titanium mesh in repairing skull defect under the temporalis and reconstructing temporal muscle attachment points. MethodsBetween January 2009 and December 2012, 58 patients with skull defect after decompressive craniectomy at the frontal temporal region were treated. Of 58 patients, 33 were male and 25 were female, aged 17-62 years (mean, 36.2 years). The disease duration was 15 weeks to 25 months (mean, 5.8 months). The size of skull defect ranged from 8 cm×6 cm to 15 cm×12 cm. The patients underwent skull impairment patch surgery with digital 3-D titanium mesh and reconstruction of the temporal muscle attachment points at titanium mesh temporal corresponding position. ResultsThe operation time was 60-100 minutes (mean, 87 minutes). After operation, 2 cases had slight red swelling with little exudation at skin incision margin, which was cured after symptomatic treatment; 2 cases had symptom of headache, which disappeared after incision healing; primary healing of incision was obtained in the other patients. Fifty-eight patients were followed up 6-24 months (mean, 16 months). The patients were satisfied with shaping, and had no chewing pain. Head CT after operation showed good fixation of titanium mesh and titanium nail, and satisfactory skull shape symmetry; no postoperative complication of subcutaneous effusion, intracranial bleeding, titanium mesh loosening, or titanium mesh exposure occurred. ConclusionThe surgery technique of digital 3-D titanium mesh to repair skull defect in frontal temporal region and to reconstruct temporal muscle attachment points at the corresponding position of titanium mesh, basically can obtain anatomical reduction of the skull, frontal temporal, and each layer of scalp. It has the advantages of less complication, less titanium nail, and satisfactory shape.
Objective To investigate the effects of titanium modified by ultrasonic acid etching/anodic oxidation (UAT) loaded with endothelial progenitor cells-exosome (EPCs-exo) on proliferation and osteogenic and angiogenic differentiations of adipose-derived stem cells (ADSCs). Methods The adipose tissue and bone marrow of 10 Sprague Dawley rats were harvested. Then the ADSCs and EPCs were isolated and cultured by collagenase digestion method and density gradient centrifugation method, respectively, and identified by flow cytometry. Exo was extracted from the 3rd to 5th generation EPCs using extraction kit, and CD9 and CD81 were detected by Western blot for identification. The three-dimensional printed titanium was modified by ultrasonic acid etching and anodic oxidation to prepare the UAT. The surface characteristics of UAT before and after modification was observed by scanning electron microscopy; UAT was placed in EPCs-exo solutions of different concentrations (100, 200 ng/mL), and the in vitro absorption and release capacity of EPCs-exo was detected by BCA method. Then, UAT was placed in DMEM medium containing different concentrations of EPCs-exo (0, 100, 200 ng/mL), and co-cultured with the 3rd generation ADSCs to construct UAT-ADSCs-exo. Cell morphology by laser confocal microscopy, live/dead cell staining, and cell proliferation were observed to evaluate biocompatibility; alkaline phosphatase (ALP) staining and alizarin red staining, RT-PCR detection of osteogenesis-related genes [osteocalcin (OCN), RUNT-related transcription factor 2 (Runx2), ALP, collagen type 1 (COL-1)] and angiogenesis-related gene [vascular endothelial growth factor (VEGF)], immunofluorescence staining for osteogenesis (OCN)- and angiogenesis (VEGF)-related protein expression were detected to evaluate the effect on the osteogenic and angiogenic differentiation ability of ADSCs. Results Scanning electron microscopy showed that micro-nano multilevel composite structures were formed on the surface of UAT. About 77% EPCs-exo was absorbed by UAT within 48 hours, while EPCs-exo absorbed on the surface of UAT showed continuous and stable release within 8 days. The absorption and release amount of 200 ng/mL group were significantly higher than those of 100 ng/mL group (P<0.05). Biocompatibility test showed that the cells in all concentration groups grew well after culture, and the 200 ng/mL group was better than the other groups, with fully spread cells and abundant pseudopodia, and the cell count and cell activity were significantly higher than those in the other groups (P<0.05). Compared with the other groups, 200 ng/mL group showed enhanced ALP activity and mineralization ability, increased expressions of osteogenic and angiogenic genes (OCN, Runx2, COL-1, ALP, and VEGF), as well as increased expressions of OCN and VEGF proteins, with significant differences (P<0.05). Conclusion EPCs-exo can effectively promote the adhesion, proliferation, and osteogenic and angiogenic differentiation of ADSCs on UAT surface, the effect is the most significant when the concentration is 200 ng/mL.
ObjectiveTo review the current research and application progress of three-dimentional (3D) printed porous titanium alloy after tumor resection, and provide direction and reference for the follow-up clinical application and basic research of 3D printed porous titanium alloy. MethodsThe related literature on research and application of 3D printed porous titanium alloy after tumor resection in recent years was reviewed from three aspects: performance of simple 3D printed porous titanium alloy, application analysis of simple 3D printed porous titanium alloy after tumor resection, and research progress of anti-tumor 3D printed porous titanium alloy. Results3D printing technology can adjust the pore parameters of porous titanium alloy, so that it has the same biomechanical properties as bone. Appropriate pore parameters are conducive to inducing bone growth, promoting the recovery of skeletal system and related functions, and improving the quality of life of patients after operation. Simple 3D printed porous titanium alloy can more accurately match the bone defect after tumor resection through preoperative personalized design, so that it can closely fit the surgical margin after tumor resection, and improve the accuracy and efficiency of the operation. The early and mid-term follow-up results show that its application reduces the postoperative complications such as implant loosening, subsidence, fracture and so on, and enhances the bone stability. The anti-tumor performance of 3D printed porous titanium alloy mainly includes coating and drug-loading treatment of pure 3D printed porous titanium alloy, and some progress has been made in the basic research stage. ConclusionSimple 3D printed porous titanium alloy is suitable for patients with large and complex bone defects after tumor resection, and the anti-tumor effect of 3D printed porous titanium alloy can be achieved through coating and drug delivery.
Objective To observe the effect of threaded titanium cage and transpedical screw for the treatment of lumbar spondylolisthesis. Methods Eighteen patients with lumbar spondylolisthesis were adopted in this study. Among them, there were 8 males and 10 females, aged from 43 to 62 years old .Roentgenogramshowed that there were 6 cases of Ⅰ° spondylolisthesis, 11 cases of Ⅱ° and 1 case of Ⅲ°. All patients were treated with cages for intervertebral fusion after total laminectomy and pedicle screws for the reduction. Results The cases were followed up from 6 to 12 months with an average of 11 months. The clinical results were excellent in 13 cases and good in 5 cases. All patients achieved successful fusion and bony union . There were no pedicle screw loosening or broken or peripheral nerve dysfunction in this series. Conclusion This method has been proved to be an effective and reliable procedure for treatment of lumbar spondylolithesis. It produces a high fusion rate and clinical success.
Objective To systematically review the effectiveness and safety of power chain vs. nickel titanium coil springs in closing dental extraction space. Methods Databases including PubMed, EMbase, The Cochrane Library, Chinese Biomedicine Literature Database, Chinese Scientific Journals Full-text Database, and Chinese Journal Full-text Database were searched to collect the randomized controlled trials (RCTs) on comparing power chain with nickel titanium coil springs published before February 2012. Two reviewers independently screened literature, extracted data and assessed the quality of the included studies. Then meta-analysis was conducted using RevMan 5.0 software. Results A total of 4 RCTs involving 122 patients were included. The results of meta-analyses showed that there was a significant difference in the rate of space closure between the two groups (MD=0.30 mm per month, 95%CI 0.17 to 0.44, Plt;0.000 1); The results of subgroup analyses indicated that, both high-quality trials (MD=0.20, 95%CI 0.07 to 0.34, P=0.003) and low quality trials (MD=0.40, 95%CI 0.30 to 0.50, Plt;0.000 01) showed no significant difference in the rate of space closure. Conclusion Current clinical evidence indicates nickel titanium coil spring is superior to power chain in the rate of space closure, but its long-term effect still needs to be proved by more large-scale RCTs.
Objective To evaluate the effectiveness of using titanium alloy trabecular bone three-dimensional (3D) printed artificial vertebral body in treating cervical ossification of the posterior longitudinal ligament (OPLL). Methods A retrospective analysis was conducted on clinical data from 45 patients with cervical OPLL admitted between September 2019 and August 2021 and meeting the selection criteria. All patients underwent anterior cervical corpectomy and decompression, interbody bone graft fusion, and titanium plate internal fixation. During operation, 21 patients in the study group received titanium alloy trabecular bone 3D printed artificial vertebral bodies, while 24 patients in the control group received titanium cages. There was no significant difference in baseline data such as gender, age, disease duration, affected segments, or preoperative pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), vertebral height, and C2-7 Cobb angle (P>0.05). Operation time, intraoperative blood loss, and occurrence of complications were recorded for both groups. Preoperatively and at 3 and 12 months postoperatively, the functionality and symptom relief were assessed using JOA scores, VAS scores, and NDI evaluations. The vertebral height and C2-7 Cobb angle were detected by imaging examinations and the implant subsidence and intervertebral fusion were observed. Results The operation time and incidence of complications were significantly lower in the study group than in the control group (P<0.05), while the difference in intraoperative blood loss between the two groups was not significant (P>0.05). All patients were followed up 12-18 months, with the follow-up time of (14.28±4.34) months in the study group and (15.23±3.54) months in the control group, showing no significant difference (t=0.809, P=0.423). The JOA score, VAS score, and NDI of the two groups improved after operation, and further improved at 12 months compared to 3 months, with significant differences (P<0.05). At each time point, the study group exhibited significantly higher JOA scores and improvement rate compared to the control group (P<0.05); but there was no significantly difference in VAS score and NDI between the two groups (P>0.05). Imaging re-examination showed that the vertebral height and C2-7 Cobb angle of the two groups significantly increased at 3 and 12 months after operation (P<0.05), and there was no significant difference between 3 and 12 months after operation (P>0.05). At each time point, the vertebral height and C2-7 Cobb angle of the study group were significantly higher than those of the control group (P<0.05), and the implant subsidence rate was significantly lower than that of the control group (P<0.05). However, there was no significant difference in intervertebral fusion rate between the two groups (P>0.05). Conclusion Compared to traditional titanium cages, the use of titanium alloy trabecular bone 3D-printed artificial vertebral bodies for treating cervical OPLL results in shorter operative time, fewer postoperative complications, and lower implant subsidence rates, making it superior in vertebral reconstruction.
ObjectiveTo compare the biomechanical characteristics of self-made nickel-titanium shape memory alloy stepped plate with calcaneal plate and cannulated compression screws in fixing calcaneal osteotomy.MethodsCalcaneal osteotomy was operated on 6 fresh-frozen lower limbs collected from donors. Then three kinds of fixation materials were applied in random, including the self-made nickel-titanium shape memory alloy stepped plate (group A), calcaneal plate (group B), and cannulated compression screws (group C). Immediately after fixation, axial loading of 20-600 N and 20 N/s in speed was introduced to record the biomechanical data including maximum displacement, elastic displacement, and maximum load. Then fatigue test was performed (5 Hz in frequency and repeat 3 000 times) and the same axial loading was introduced to collect the biomechanical data. Finally, the axial compression stiffness before and after fatigue test were calculated.ResultsThere was no significant difference in the axial compression stiffness between pre- and post-fatigue test in each group (P>0.05). However, the axial compression stiffness was significant higher in group A than that in groups B and C both before and after fatigue test (P<0.05). No significant difference was found between group B and group C (P>0.05).ConclusionSelf-made nickel-titanium shape memory alloy stepped plate is better than calcaneal plate and cannulated compression screws in axial load stiffness after being used to fix calcaneal osteotomy.
ObjectiveTo investigate the effectiveness of mini titanium plate for the treatment of intracapsular condylar fractures-type A. MethodsBetween March 2013 and July 2015, 22 cases (26 sides) of intracapsular condylar fractures-type A were treated with mini titanium plate through anterior auricular approach. There were 13 males and 9 females, aged from 16 to 32 years (mean, 22.7 years). The disease causes were traffic accident injury in 17 cases, falling injury in 4 cases, and heavy impact injury in 1 case. Five cases had intracapsular condylar fractures-type A only, and the other cases were accompanied with fractures of mandible, maxillary, or other part of jaw. All patients had different degrees of limitation of opening mouth, occlusal disorder, and joint pain, and the maximum opening was 5-16 mm (mean, 8.6 mm). All patients received surgical treatment within 2 to 9 days after injury (mean, 4 days). The clinical dysfunction index (DI) of Helkimo index was used to evaluate the mandibular motor function postoperatively. According to the 4 basic criterion of cure about mandibular condylar fractures by the international consensus conference in 1999, and maximal mouth opening by HE Dongmei et al., the surgical treatment effectiveness was evaluated. ResultsAll wounds healed at stage I, with no infection or other complications. All 22 cases were followed up 5-8 months (mean, 6 months). At 1 week after operation, the coronal spiral CT and three-dimensional reconstruction showed that contraposition of fractures was good, and the condyles located in the articular fossa. At 6 months after operation, the maximum opening was 33-42 mm (mean, 35.7 mm). After operation, 3 cases showed the mandible deflected to the affected side when opening, and limited lateral motion. According to the DI evaluation method in Helkimo index, there were 7 sides of DI grade 0, 18 sides of DI grade I, and 1 side of DI grade II. Based on surgical treatment effect of intracapsular condylar fractures-type A, occlusion recovery was obtained in 19 cases (86.36%), maximum opening degree of≥35 mm in 20 cases (90.91%), no symptoms of joint injury in 19 cases (86.36%), and no serious postoperative complications in 22 cases (100%); 17 cases (77.27%) were in accordance with the above 4 items. ConclusionMini titanium plate is one of the most effective approaches to treat intracapsular condylar fractures-type A.