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08 February 2020, Volume 24 Issue 4 Previous Issue    Next Issue

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Bone healing effects of early-stage versus late-stage bone grafting within induced membrane Zhou Zihong, Wu Yongwei, Feng Dehong, Zhao Jijun, Gu Sanjun, Xu Yajun, Rui Yongjun, Yin Xiaogen, Yin Qudong 2020, 24 (4):  493-498.  doi: 10.3969/j.issn.2095-4344.1963 Abstract ( 367 )   PDF (27624KB) ( 92 )   Save BACKGROUND: It remains unclear regarding the difference in bone healing effects after early-stage versus late-stage bone grafting within induced membrane. OBJECTIVE: To investigate the difference in bone healing effects of bone grafting within induced membrane in the repair of bone defects and the major factors that affect bone healing. METHODS: Sixty-three patients with tibial bone defect who received treatment with induced membrane technique during January 2007 to August 2017 in Wuxi People’s Hospital and Wuxi Orthopedics Hospital, China. These patients consisted of 38 males and 25 females and were aged 16-69 years. According to the time of bone grafting within induced membrane after bone cement filling, these patients were divided into an early stage group (n=25, bone grafting in the induced membrane 6-8 weeks after filling bone cement) and a late stage group (n=38, bone grafting in the induced membrane 10-12 weeks after filling bone cement). The healing of bone defect and functional recovery of affected limbs were evaluated. The causes of delayed healing and nonunion were analyzed. This study was approved by the Medical Ethics Committee of Wuxi People’s Hospital and Wuxi Orthopedics Hospital, China (approval No. LW2019001). RESULTS AND CONCLUSION: Bone graft was successfully completed in 63 patients. The induced membrane formed in the early stage group was thin and there were relatively more capillaries, while the induced membrane formed in the late stage group was usually thick and there were relatively few capillaries. All 63 patients were followed up for 16-50 months. In the early stage group, the wound or incision healed at first intention in 22 patients and delayed healing was observed in 3 patients. In the late stage group, the wound or incision healed at first intention in 34 patients, delayed healing was observed in 2 patients, and healing by the second intention was observed in 2 patients. In the early stage group, there was 1 patient developing delayed healing, no nonunion was observed, the clinical healing time was averaged 6.64 (range 5.0-12.0 months) months. In the late stage group, delayed healing occurred in 2 patients and nonunion was observed in 1 patient. The clinical healing time was averaged 7.42 (range 5.0-16.0 months) months. There were no significant differences in the healing time and nonunion between the early stage and late stage groups (P > 0.05). In the early stage group, excellent functional recovery of affected limb was observed in 13 patients, good recovery in 11 patients, and fair recovery in 1 patient, and it was 17, 18 and 3 patients respectively in the late stage group. There was no significant difference in functional recovery of affected limbs between early stage and late stage groups (P > 0.05). These results showed that bone grafting within the induced membrane at different time has slight, but not significant effect on healing of bone defect. Other factors, such as the size and the integrity of induced membrane, the quality and quantity of bone graft material, and the stability of bone stumps had more significant effects on the healing of bone defects, in particular on the healing rate.  Figures and Tables | References | Related Articles | Metrics

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Absorbable suture anchors for treating femoroacetabular impingement syndrome combined with acetabular labral tears Ai Di 2020, 24 (4):  499-504.  doi: 10.3969/j.issn.2095-4344.2222 Abstract ( 657 )   PDF (27086KB) ( 67 )   Save BACKGROUND: Metal anchors are not easily accepted by patients as permanent foreign bodies, so bioabsorbable anchors have been gradually applied in orthopedics in recent years. OBJECTIVE: To evaluate the effectiveness of absorbable suture anchors for repairing femoroacetabular impingement syndrome combined with acetabular labral tears. METHODS: Eighty patients with femoroacetabular impingement syndrome combined with acetabular labral tears admitted in Beijing Shijitan Hospital Affiliated to Capital Medical University from February 2014 to February 2016 were selected, and all were treated by absorbable suture anchors under arthroscopy. The Harris hip score, and the Visual Analogue Scale score at baseline, postoperative 1 and 3 months were recorded and compared to assess the effectiveness. The complications and material-host reaction were recorded. The treatment satisfaction was evaluated. The study was approved by the Ethical Committee of Beijing Shijitan Hospital and all patients and their families signed the informed consents. RESULTS AND CONCLUSION: (1) The Harris hip scores at 1 and 3 years postoperatively in 80 patients with femoroacetabular impingement syndrome combined with acetabular labral tears were significantly higher than those at baseline, and the Visual Analogue Scale scores were significantly lower than those at baseline (P < 0.05). (2) The excellent and good rate of treatment in patients at 1 and 3 years was 90.0% and 97.50%, respectively, and the treatment satisfaction was 87.4% and 93.8%, respectively. The excellent and good rate of treatment and treatment satisfaction presented an increased trend with time, but had no significant difference (P > 0.05). (3) None appeared with anchor drop off, cartilage injury or material-host reaction. In summary, the method of absorbable suture anchors under arthroscopy has the advantages of minimal invasion, reliable fixation, simple operation, no metal implants, and significant clinical effect to treat femoroacetabular impingement syndrome combined with acetabular labral tears. Figures and Tables | References | Related Articles | Metrics

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A study on anterior cruciate ligament injury and knee stability with a silicon mesh brace Jing Xiaowei, Mu Yingxiu 2020, 24 (4):  505-510.  doi: 10.3969/j.issn.2095-4344.1927 Abstract ( 395 )   PDF (23350KB) ( 67 )   Save BACKGROUND: Knee braces have been shown to improve knee mechanics in the case of slow walking, but most studies lack the data regarding the effects of a brace on knee injury in the case of lack of movement.  OBJECTIVE: Jumping, emergency stop, rotation which easily induce knee joint injury during the rapid exercise were simulated to investigate whether silicon mesh braces can provide stable support for the knee joint and provide data support for the protection against anterior cruciate ligament injury.  METHODS: Twelve healthy subjects were selected to perform three movements: squatting, one-leg jump and steering jump respectively with and without a brace. Reflection markers were placed on the feet, calves, thighs, and pelvis of the subjects. A Qualisys motion capture system was used to obtain kinematic data of the knee joints. Knee joint motion was compared between with and without a brace. This study was performed by Medical Ethics Committee of Guizhou College of Traditional Chinese Medicine on August 8, 2018 (approval No. 2018661). RESULTS AND CONCLUSION: There were significant differences in the angle and angular velocity of the knee joint among sagittal plane, coronal plane, and horizontal plane. The knee joint valgus and internal rotation angle were reduced when wearing a brace in particular in one-leg jump and steering jump. The angular velocity of horizontal surface rotation also decreased obviously when wearing a brace. These findings suggest that wearing a brace can affect the motion mechanics of the knee joint in the coronal and horizontal planes. This suggests that knee joint can effectively control the stability when wearing a brace in the process of dynamic movement, and wearing a brace can improve the control of knee peak valgus angular velocity and external rotation angular velocity, which can help effectively prevent anterior cruciate ligament injury of patients with anterior cruciate ligament defects. Figures and Tables | References | Related Articles | Metrics

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Construction of periodontal biomimetic membrane with electrospun poly(lactic-co-glycolic acid) nanofibers and electrosprayed chitosan microspheres Feng Xiaoxia, Hou Weiwei, Jin Xiaoting, Wang Xinhua 2020, 24 (4):  511-516.  doi: 10.3969/j.issn.2095-4344.2212 Abstract ( 532 )   PDF (25956KB) ( 77 )   Save BACKGROUND: When the teeth are separated from the alveolar fossa, the periodontal membrane breaks, and the residual periodontal membrane on the avulsed tooth root surface changes from three-dimensional to two-dimensional, thus losing the role of scaffold, and leading to root bone adhesion after replantation of avulsed tooth. How to develop a three-dimensional sustained-release scaffold material that can adhere to the root surface with a certain thickness and strength is one of the key factors for successful regeneration of avulsed tooth periodontal membrane. OBJECTIVE: To construct a three-dimensional periodontal biomimetic membrane that can adhere to the avulsed tooth root surface and allow sustained-release of growth factors. METHODS: Poly(lactic-co-glycolic acid) (PLGA) membrane was prepared using electrospinning technique. The effects of dichloromethane and dimethylformamide mixture, hexafluoroisopropanol, and trichloromethane on electrospun membrane were investigated to obtain the optimal electrospinning solvent. Chitosan microspheres were prepared by electrospray and ion cross-linking techniques. The effects of molecular weight (50,000,100,000) and mass concentration (10, 20 g/L) of chitosan, sodium tripolyphosphate concentration (2%, 5%, 10%) and voltage (14, 28 kV) on chitosan microspheres were studied to screen the optimum parameters. Chitosan microspheres containing stromal cell-derived factor-1 (optimal parameter design) were constructed. The release rate of stromal cell-derived factor-1 alpha in vitro was determined. First, the root surface of teeth was wrapped with electrospun PLGA membrane, then chitosan microspheres were dripped on the surface, and finally the surface was wrapped with a thin layer of electrospun PLGA. Thus, PLGA-chitosan-PLGA biomimetic membrane was constructed. RESULTS AND CONCLUSION: Electrospun PLGA membrane prepared with hexafluoroisopropanol as electrospinning solvent had the smallest average diameter and the largest porosity. When the relative molecular weight of chitosan was 50,000 and the mass concentration was 20 g/L, the size of chitosan microspheres was basically the same, and the average diameter was 366.6 μm. In addition, chitosan microsphere had good monodispersity, fullness, and stability. Chitosan microspheres formed under 28 kV voltage and were more in line with the requirements of biomimetic membrane for avulsed tooth. The surface of microspheres prepared by 5% sodium tripolyphosphate had medium-sized pores, which are most conducive to clinical periodontal membrane regeneration. Chitosan microspheres can sustainably release stromal cell derived factor 1alpha for about 1 month. In this study, we constructed a three-dimensional PLGA-chitosan-PLGA periodontal biomimetic membrane that can adhere to the avulsed tooth root surface and allow sustained-release of growth factors and obtained the optimal parameters of constructing the periodontal biomimetic membrane. Based on the PLGA-chitosan-PLGA periodontal biomimetic membrane, the effect and mechanism of tissue engineering on replantation of avulsed tooth can be further studied. Figures and Tables | References | Related Articles | Metrics

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Effect of different smear layers on the bonding performance and durability of four adhesive systems Zheng Shize, Li Ke, Chen Yue, Yan Xiaoyuan, Zhan Desong, Fu Jiale 2020, 24 (4):  517-523.  doi: 10.3969/j.issn.2095-4344.2223 Abstract ( 585 )   PDF (30692KB) ( 56 )   Save BACKGROUND: When the tooth surface is treated with a rotary or manual instrument, a smudge layer is formed on the enamel and dentin by debris generated by cutting and abrasion. The bonding interface between the adhesive and the dentin is considered as a weak part in the direct repair process. To clarify the effect of smear layer on different kinds of adhesive is significantly important for dentists to select and correctly use the adhesive in clinical treatment. OBJECTIVE: To evaluate the effect of different diamond burs on the dentin bonding performance of four adhesive systems to dentin after 24 hours and 100 days of artificial saliva-storage. METHODS: Adhesive systems were: (1) VSA (Optibond Versa, Kerr); (2) AIO (Optibond All in One, Kerr); (3) SBU (Single bond Universal, 3M); (4) GLU (Bond 5, Gluma,Heraeus). In present study, 80 extracted human molars were randomly divided into four groups and each group is divided into 4 subgroups. Dentin surfaces were prepared by: (1) 600-grit SiC-paper (control group); (2) super-fine diamond bur; (3) regular diamond bur; (4) coarse diamond bur. Bonding agent was applied according to each manufacturer’s instruction. After light-curing, dentin surfaces were built-up with resin composite (A2, CHARISMA, Heraeus). The micro-tensile bond strength was determined after 24 hours and 100 days of storage in artificial saliva at 37 °C. The fractured surfaces on dentin side were observed by scanning electron microscope. RESULTS AND CONCLUSION: (1) Storage for 24 hours: there was no significant difference among groups under VSA and GLU. Under SBU and AIO, the bond strength in the coarse diamond bur group was significantly lower than that in the control group (P < 0.05). Using 600-grit SiC-paper or regular diamond bur, the bond strength showed no significant difference only between AIO and VSA groups. Using regular diamond bur, the bond strength showed no significant difference in the VSA group compared with the AIO, GLU and SBU groups (P > 0.05). Using coarse diamond bur, the bond strength in the VSA group had significant difference compared with the AIO, GLU and SBU groups (P < 0.05), and other groups had no significant difference (P > 0.05). (2) Storage for 100 days, there was no significant difference among groups under VSA and GLU. Under SBU, the bond strength in the coarse diamond bur group was significantly lower than that in the control group (P < 0.05). Using 600-grit SiC-paper, the bond strength showed no significant difference only between VSA and SBU groups (P > 0.05). Using regular diamond bur, the bond strength showed no significant difference in the GLU group compared with the SBU, and VSA groups (P > 0.05). Using coarse diamond bur, the bond strength had no significant difference between VSA and AIO groups (P < 0.05). (3) Using VSA, the bond strength in each group at 100 days showed significant difference compared with that at 24 hours (P < 0.05). (4)Compared with immersed for 24 hours, the ratio of bond interface and combined crack in the VSA, SBU and GLU groups after immersed for 100 days was increased, especially the VSA group. Compared with the other groups, the ratio of bond interface and combined crack in the GLU group after immersed for 24 hours and 100 days both increased by 50%. (5) These results indicate that preparation by different burs produces different smear layers, which has significant effect to self-etching adhesive system and has no significant effect to total-etching adhesive system. Storage time makes effect on different adhesives. Figures and Tables | References | Related Articles | Metrics

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Fabrication and evaluation of biomimetic biodegradable tissue-engineered annulus fibrosus scaffold Zhang Weihao, Xu Baoshan, Ma Xinlong, Zhang Yang, Guo Yue, Du Lilong, Xu Haiwei, Zhang Kaihui, Xia Jinjian, Shao Pengfei 2020, 24 (4):  524-531.  doi: 10.3969/j.issn.2095-4344.1883 Abstract ( 348 )   PDF (31116KB) ( 70 )   Save BACKGROUND: It is still difficult to construct tissue-engineered anulus fibrosus scaffolds which have bionic structure, suitable biodegradability and good biocompatibility. OBJECTIVE: To fabricate bionic biodegradable scaffolds with polycaprolactone (PCL) and polydioxanone (PDS) and evaluate the feasibility as a tissue-engineered annulus fibrosus scaffold. METHODS: Five groups of scaffolds at different PCL/PDS proportions were prepared by melt spinning technique: PCL, PCL/PDS70/30, PCL/PDS50/50, PCL/PDS30/70, and PDS groups. Scanning electron microscopy was used to observe the structure and measure the fiber diameter and pore size of these prepared scaffolds. The mechanical properties and contact angle of the scaffolds were measured. The in vitro and in vivo biodegradation of the scaffolds were observation by in vitro simulation and subcutaneous implantation. The expression of inflammatory factors interleukin-1β and tumor necrosis factor-α in the biodegraded tissues was detected. Human Wharton’s jelly mesenchymal stem cells were cultured for 7 days. Cell viability and proliferation was determined by live/dead cell staining. This study was approved by the Medical Ethics Committee of Tianjin Hospital, China on March 2, 2016. RESULTS AND CONCLUSION: Scanning electron microscopy results showed that the thickness of the scaffold fibers was uniform and the angle between fibers was 60°. The mechanical properties analysis showed that the tensile and compressive modulus of the PDS group was the lowest, which did not meet the mechanical requirements of the anulus fibrosus; the tensile and compressive modulus in the PCL group was the highest, and those in the PCL/PDS70/30 and PCL/PDS50/50 group were moderate. Hydrophilicity test showed that higher PDS proportion led to better hydrophilicity. Biodegradation test showed that the biodegradation of pure PDS and PCL/PDS30/70 was too fast, that of PCL was too slow, and that of PCL/PDS70/30 and PCL/PDS50/50 was appropriate. Analysis of inflammatory response around the biodegraded tissue showed that higher proportion of PCL in the scaffold resulted in more severe inflammatory response. CCK-8 and live/dead cell staining showed that human Wharton’s jelly mesenchymal stem cells had good proliferative activity and high survival rate in the PCL/PDS70/30, PCL/PDS50/50, and PCL/PDS30/70 groups. These results suggest that scaffolds in the PCL/PDS70/30 and PCL/PDS50/50 groups can simulate the structure of natural annulus fibrosus, have appropriate biodegradability, excellent mechanical properties and good biocompatibility, which make it a suitable candidate for tissue-engineered annulus fibrosus scaffold. Figures and Tables | References | Related Articles | Metrics

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Bone marrow mesenchymal stem cells combined with acellular dermal matrix repair beagle dog articular cartilage defects  Jin Shaofeng, Zheng Rui, Jie Yongsheng, Chen Lei, Qi Hui, Sun Lei, Shu Xiong 2020, 24 (4):  532-537.  doi: 10.3969/j.issn.2095-4344.1405 Abstract ( 484 )   PDF (25904KB) ( 77 )   Save BACKGROUND: Dermis-derived extracellular matrix, as a cartilage repair scaffold, provides a space for the growth of cartilage tissue, and promotes cell adhesion and proliferation. Bone marrow mesenchymal stem cells have the potential to differentiate into chondrocytes. Both of them used alone have disadvantages. OBJECTIVE: To evaluate the feasibility of bone marrow mesenchymal stem cells combined with calf acellular dermal matrix to repair beagle dog articular cartilage defects. METHODS: Beagle dog bone marrow blood was extracted from Beagle dogs. Bone marrow mesenchymal stem cells were obtained by density gradient centrifugation and passaged. Acellular dermal matrix was prepared from the dorsal dermis of neonatal calves by ultrasonic oscillation, freeze-drying and pepsin. 0.2 mL of cell suspension was added to the surface of acellular dermal matrix until covered, then which was placed in a 5% CO2 incubator at 37 °C for 48 hours. Twelve adult beagle dogs were used to establish knee joint cartilage defect models, and then randomized into three groups: In the acellular dermal matrix combined with bone marrow mesenchymal stem cells group (combination group), cartilage defects were repaired with acellular dermal matrix combined with bone marrow mesenchymal stem cells. In the single acellular dermal matrix group, cartilage defects were repaired with acellular dermal matrix. The model control group received no treatment. At 12 weeks after surgery, the right knee joints were observed by stereomicroscope, hematoxylin-eosin staining and type II collagen immunohistochemical staining. RESULTS AND CONCLUSION: (1) Scanning electron microscopy showed that bone marrow mesenchymal stem cells adhered to and grew well in the acellular dermal matrix. (2) Hematoxylin-eosin staining revealed that the repaired surface in the combination group was slightly lower than that of the surrounding normal tissues, and the repaired tissues integrated well with the surrounding cartilages. The defects in the single acellular dermal matrix group were filled with fibrous tissues. Few surrounding tissues of defect were repaired in the model control group. (3) Type II collagen immunohistochemical staining showed that in the combination group, articular cartilage defects were filled with chondrocyte-like tissues. In the single acellular dermal matrix group, the defect was filled with fibrous tissues. No tissue was found in the model control group. (4) These results indicate that the new calf acellular dermal matrix has good biocompatibility and can promote the proliferation of bone marrow mesenchymal stem cells. Autologous bone marrow mesenchymal stem cells combined with acellular dermal matrix can effectively repair beagle dog knee joint cartilage defects. Figures and Tables | References | Related Articles | Metrics

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Factors affecting the clinical success rate of miniscrew implants for orthodontic treatment Wu Yeke, Gao Ranran, Zuo Yuling, Yu Jianfeng, Zhao Lixing, Nie Wenhan, Zheng Tao, Ai Huangping, Yan Hang 2020, 24 (4):  538-543.  doi: 10.3969/j.issn.2095-4344.1925 Abstract ( 515 )   PDF (22887KB) ( 63 )   Save BACKGROUND: During the orthodontic treatment, the results of related reports on potential risk factors affecting the clinical success rate of miniscrew implants are inconsistent. The influential factors that clinicians concern are not all included in this study, and the conclusions from animal experiments are difficult to apply to clinical practice directly. Therefore, what factors affect the clinical success rate of miniscrew implants need further thorough and systematic research. OBJECTIVE: To investigate the factors that influence the clinical success rate of miniscrew implants used as orthodontic anchorage. METHODS: A total of 114 patients with oral implants, including 42 males and 72 females, aged (19.26±9.19) years were included in this study. A total of 253 miniscrew implants were implanted as orthodontic anchorage. The following influential factors were included: gender, age, vertical skeletal facial pattern, implant site, implant arch, soft tissue type at the implant site, oral hygiene status, diameter and length of the miniscrew implants, implantation method, implantation angle, stress loading timing and intensity, and clinical use. Logistic regression analysis was used to study the correlation between success rate and all variables. Analysis of variance was used to test the effect of each variable on clinical success rate. This trial protocol was approved by the Medical Ethics Committee of Sichuan University. RESULTS AND CONCLUSION: Among 253 successful miniscrew implants, the overall success rate was 88.54% with an average loading period of 9.5 months. The average loading period of the 29 failed miniscrew implants was 2.3 months. The chi-square test, Fisher exact test and Logistic regression revealed that age, oral hygiene, vertical skeletal facial pattern, and implant site were significantly correlated with clinical success rate (P < 0.05). However, gender, sagittal bone facial patter, implant arch, soft tissue type at implant site, diameter and length of miniscrew implant, implantation method, implantation angle, stress loading timing and strength, and clinical use were not significantly correlated to clinical use (P > 0.05). These results suggest that to minimize the failure of miniscrew implants, proper oral hygiene instruction and effective supervision should be given to patients, in particular to those young (< 12 years) high mandibular plane patients.  Figures and Tables | References | Related Articles | Metrics

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Application of intraoral scanning and 3D printing in the manufacture of removable partial dentures Su Tingshu, Tang Ying, Sun Jian 2020, 24 (4):  544-548.  doi: 10.3969/j.issn.2095-4344.2208 Abstract ( 473 )   PDF (22839KB) ( 74 )   Save BACKGROUND: There is no mature computer-aided design and manufacturing system for the preparation of removable partial denture in China so far. There is no report involving large sample size. Most of the existing studies only investigated the wear effect of a few cases, and there is a need to accumulate and enrich clinical data. OBJECTIVE: To explore the application value of intraoral scanning and 3D printing in the manufacture of removable partial dentures for patients. METHODS: Sixty-three patients with Kennedy class I dentition defect who received treatment in the Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine, China were included in this study. These patients consisted of 29 males and 34 females and were aged 44-63 years. In the study group, 23 patients were treated with denture scaffolds by intraoral scanning and three-dimensional printing, while in the control group, 40 patients were treated with denture scaffolds by traditional impression. The wear effect was compared between two groups after repair. The masticatory efficiency was compared between two groups before and 6, 12 and 24 months after repair. At the last follow-up, patients' satisfaction and complications were compared between the study and control groups. This study was approved by Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine (approval No. TJBDYY-2014-13-R1) in March, 2014. RESULTS AND CONCLUSION: The fitness (96% vs. 70%), retention (83% vs. 58%) and stability index (83% vs. 53%) of the study group were significantly higher than those of the control group (all P < 0.05). There was no significant difference in masticatory efficiency between before and 6 months after repair (P > 0.05). At 12 and 24 months after repair, the masticatory efficiency in the study group was significantly higher than that in the control group (P < 0.05). Patients' comfort satisfaction in the study group was significantly higher than that in the control group (82% vs. 50%, P < 0.05). There were no significant differences in aesthetic appearance (70% vs. 53%) and pronunciation function satisfaction (65% vs. 40%) between study and control groups. During the follow-up, there were no statistically significant differences in the incidences of periodontal disease (0 vs. 5%), denture stomatitis (4% vs. 5%) and secondary caries (9% vs. 18%) between groups (P > 0.05). These results suggest that intraoral scanning and 3D printing could obtain a more accurate stent model in the manufacture of partial dentures compared with traditional impression, thereby has a higher application value. Figures and Tables | References | Related Articles | Metrics

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Silicone stent insertion for treating tracheobronchomalacia in adults Li Xiao, Pan Jinbing, Ma Yun, Qian Haoyu, Zhang Quncheng, Wang Zheng 2020, 24 (4):  549-554.  doi: 10.3969/j.issn.2095-4344.2210 Abstract ( 535 )   PDF (25270KB) ( 84 )   Save BACKGROUND: Silicone tracheobronchial stent insertion can provide symptomatic relief through airway stabilization in patients with symptomatic tracheobronchomalacia. However, there are few studies on this method. OBJECTIVE: To evaluate the safety and efficacy of silicone stents in the treatment of tracheobronchomalacia. METHODS: Eight tracheobronchomalacia patients who underwent silicone stent implantation at Henan Provincial People’s Hospital between September 2015 and December 2018 were included in this study. According to the location and degree of airway softening, appropriate silicone stents were designed. Silicone stents were implanted in all eight patients, including hourglass stents in 2 cases, straight tube stents in 2 patients, Y-shaped stents in 3 patients, and T-shaped stents in 1 patient. All patients provided informed consent and this study was approved by the Medical Ethics Committee of Henan Provincial People's Hospital, China. Blood gas analysis was performed before and 30 days after surgery to measure blood oxygen level. Quality of life was assessed by card score. The position of stent, intraluminal endocrine, and granulation growth were dynamically monitored by bronchoscopy at 7, 30 and 60 days after surgery. RESULTS AND CONCLUSION: Silicone airway stents were placed successfully in seven patients. Dyspnea was relieved immediately. One patient had rupture of left main bronchial membrane during the procedure of insertion. The partial oxygen pressure and chi-square score of seven patients at 30 days after surgery were significantly higher than those before surgery (t=-8.60, -20.76, P < 0.05). Tracheoscopy revealed that stent displacement occurred in 3 patients, difficulty in sputum expectoration and mild granulation tissue hyperplasia occurred in 3 patients, and improved after endoscopic treatment. The results suggest that silicone stent insertion in patients with tracheobronchomalacia can alleviate the symptoms of patients. Although the incidence of silicone stent displacement and sputum obstruction is high, silicone stent insertion is still an important treatment method. Figures and Tables | References | Related Articles | Metrics

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Clinical outcomes of drug-eluting balloons and drug-eluting stents for the treatment of in-stent restenosis Xie Xiufeng, Zhang Yue, Qu Ze 2020, 24 (4):  555-560.  doi: 10.3969/j.issn.2095-4344.1890 Abstract ( 534 )   PDF (24549KB) ( 42 )   Save BACKGROUND: A series of studies have shown that both drug-eluting balloons and drug-eluting stents are better than the other treatments for drug-eluting in-stent restenosis lesions, but both of them have limitations. OBJECTIVE: To evaluate the long-term therapeutic efficacy of drug-eluting balloons and drug-eluting stents in the treatment of coronary in-stent restenosis. METHODS: A total of 63 patients with in-stent restenosis who received treatment in the First Affiliated Hospital of Inner Mongolia Medical University between January 2016 and December 2017 were included in this study. Among these patients, 32 patients received treatment with drug-eluting balloons (drug-eluting balloon group) and 31 patients were treated with drug-eluting stents (drug-eluting stent group). Coronary artery status before and immediately after surgery, coronary angiography 1 year after surgery, adverse events, and the risk factors of in-stent restenosis were recorded in both groups. The study was approved and supported by the Medical Ethics Committee of Inner Mongolia Medical University.  RESULTS AND CONCLUSION: All patients were followed up for 1 year. There were no significant differences in minimum in-stent diameter, target vessel diameter, in-stent lumen loss in the late period between patients receiving treatment with drug-eluting balloons and patients receiving drug-eluting stents (all P > 0.05). There were no significant differences in secondary restenosis rate (18% vs.16%, P=0.216), target lesion revascularization rate (6% vs. 6%, P=0.513), and incidence of adverse events (9% vs.10%, P=0.334) between drug-eluting balloon and drug-eluting stent groups. There were two cases of gastrointestinal bleeding in the drug-eluting stent group, and no gastrointestinal bleeding occurred in the drug-eluting balloon group. Significant difference in gastrointestinal bleeding occurred between these two groups (P < 0.01). Multi-factor analysis showed that smoking, diabetes and hyperhomocysteinemia are the risk factors of in-stent restenosis. These results suggest that both drug-eluting balloons and drug-eluting stents are the ideal treatments of in-stent restenosis. In clinical practice, individualized treatment options should be considered based on multiple factors. Figures and Tables | References | Related Articles | Metrics

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Hemorrhage control of fluid gelatin SurgifloTM versus gelatin sponge in lumbar spine fusion surgery Qin Wenpin, Yang Yujie, Zhao Laihe, Shi Xiaowei, Lu Lei, Yang Hongxu, Huang Jinghui 2020, 24 (4):  561-565.  doi: 10.3969/j.issn.2095-4344.2209 Abstract ( 822 )   PDF (22358KB) ( 127 )   Save BACKGROUND: Hemorrhage control has been an important issue in spine surgery. The widely used gelatin sponge is limited by its long-time bleeding control and poor hemorrhage control. Therefore, new techniques are needed to control bleeding in spine surgery. OBJRCTIVE: To compare the hemostatic effect of fluid gelatin SurgifloTM with absorbable gelatin sponge in single level posterior lumbar fusion surgery. METHODS: Ninety-eight patients consisting of 52 males and 46 females, aged 54.32 years who received treatment between September 2017 and December 2017 in Xijing Hospital of The Fourth Military Medical University were included in this study. All patients underwent single-level L4/5 lumbar fusion. Among them, 48 patients received intraoperative hemostasis with fluid gelatin SurgifloTM and 50 patients received intraoperative hemostasis with conventional gelatin sponge. Intraoperative bleeding volume, postoperative drainage volume, success rate of hemostasis in 3 minutes and changes of hemoglobin levels in perioperative period were compared between the two groups. RESULTS AND CONCLUSIONS: The operation time in the SurgifloTM group was significantly shorter than that in the gelatin sponge group [(105±26) vs. (118±32) min, P < 0.05]. The amount of intraoperative blood loss and total amount of drainage were (156±57) mL and (106±42) mL in the SurgifloTM group which were significantly lower than those in the gelatin sponge group [(204±62) mL, (148±35) mL, P < 0.05]. The success rate of hemostasis within 3 minutes in the SurgifloTM group was significantly higher than that in the gelatin sponge group (94% vs. 80%, P < 0.05). The change in hemoglobin level during the perioperative period relative to pre-surgery level was significantly higher in the SurgifloTM group was significantly lower than that in the gelatin sponge group [(12.3±3.6) vs. (22.8±4.3) g/L, P < 0.05]. No complications such as anaphylaxis, immune rejection, or delayed hematoma occurred in both groups. These results suggest that fluid gelatin SurgifloTM can significantly reduce intraoperative blood loss and postoperative drainage volume in single-level lumbar fusion surgery and exhibit better hemostatic effects. Figures and Tables | References | Related Articles | Metrics

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In vitro multi-modal imaging of magnetic targeted nanoparticles and their targeting effect on hepatic stellate cells Li Xuan, Lu Min, Li Mingxing, Ao Meng, Tang Linmei, Zeng Zhen, Hu Jingwei, Huang Zhiqiang, Xuan Jiqing 2020, 24 (4):  566-571.  doi: 10.3969/j.issn.2095-4344.2206 Abstract ( 345 )   PDF (25767KB) ( 67 )   Save BACKGROUND: In recent years, molecular imaging combined with medical imaging technology and targeted molecular probes have gradually become a research focus. The targeted tissues at the molecular level can be observed using molecular imaging, medical imaging technology, and targeted molecular probes in combination to realize non-invasive imaging of the occurrence and development of the diseases. OBJECTIVE: To develop the magnetic targeted nanoparticle probes, observe the ultrasound/CT/MRI imaging properties in vitro, and investigate their targeting ability to rat hepatic stellate cells in vitro. METHODS: Taking poly(lactic-co-glycolic acid) (PLGA) polymer as the shell, cyclic arginine-glycine-aspartic acid (cRGD) octapeptide as the ligand, targeted magnetic nanoparticles with superparamagnetic Fe3O4 embedded in the shell and perfluorooctyl bromide(PFOB) loaded in the core were prepared by double emulsion evaporation method. The physical and chemical properties of the nanoparticles were detected. The ultrasound/CT/MRI multi-modal imaging properties of the nanoparticles at different concentrations diluted with double-distilled water were tested in vitro. Cyclic RGD peptide immobilization on PLGA-Fe3O4-PFOB NPs was completed through the amide condensation reaction. The conjugation efficiency of the cRGD on PLGA-Fe3O4-PFOB NPs and targeting ability of targeted magnetic nanoparticles in vitro were verified. Cytotoxicity experiments were used to measure the toxic effects of nanoparticles at different concentrations on BRL-3A cells in each group. RESULTS AND CONCLUSION: The targeted magnetic nanoparticles with the average size of (221.5±60.3) nm were uniform in dispersion and size. The prepared individual nanoparticle was spherical with the superparamagnetic Fe3O4 scattered on the shell. The encapsulation rate of Fe3O4 was 38%. In vitro ultrasound imaging and CT imaging signal decreased gradually as the concentrations of the nanoparticle suspension decreased. The T2-weighted signal of MRI decreased gradually with the increase of the concentrations of magnetic particle Fe3O4. Flow cytometry results showed that 94.13% of the cRGD was bound to the nanoparticles. In vitro cell targeting experiments showed that compared to PLGA-Fe3O4-PFOB NPs, cRGD-PLGA-Fe3O4-PFOB NPs exhibited greater cell targeting and affinity efficiency to hepatic stellate cells. Cytotoxicity experiments results showed the nanoparticles had no significant influence on cell viability of the BRL-3A cells. These results suggest that targeted magnetic nanoprobe cannot only be used as a multi-modal imaging contrast agent for ultrasound/CT/MRI, but also exhibits a strong specific affinity to rat hepatic stellate cells in vitro. It has great potential for the early diagnosis of liver fibrosis. Figures and Tables | References | Related Articles | Metrics

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Construction of acellular porcine bladder scaffolds Li Qin, Xia Cuiping, Liu Xiaohong, Xu Zhiyun, Gong Dejun, Wu Hao 2020, 24 (4):  572-576.  doi: 10.3969/j.issn.2095-4344.1879 Abstract ( 432 )   PDF (20329KB) ( 132 )   Save BACKGROUND: Bladder repair is currently one of the main treatments for bladder defects. Homologous tissue is less affected by various factors. Tissue engineered acellular bladder matrix has become an increasing area of interest. Porcine bladder acellular matrix has a wide range of sources and has a natural extracellular scaffold structure, which has become a hot topic in tissue engineering bladder substitute materials. OBJECTIVE: To explore the feasibility of acellular porcine bladder as a tissue engineering scaffold material. METHODS: The cell-free matrix of pig bladder was prepared by liquid nitrogen freezing and thawing, dodecyl sodium sulfate and trypsin decellularization method. According to different decellularization methods, pig bladders were divided into normal control group (without any treatment), experimental group (treated with 0.6% trypsin and 5% sodium lauryl sulfate (pH 8.0)) and acellular control group (treated with 0.75% trypsin (pH 8.0), 1% trypsin (pH 8.0), 5% sodium lauryl sulfate (pH 7.6) or 10% sodium dodecyl sulfate (pH 7.6)). The decellularization effect of pig bladder was observed by hematoxylin-eosin staining, van Gieson staining, DNA quantification, and α-Gal antigen detection. RESULTS AND CONCLUSION: Hematoxylin-eosin staining revealed that in the experimental group, the components of the bladder cells of the pigs were basically removed. van Gieson staining revealed that the DNA residues and α-Gal antigen residues in the cells were significantly lower than those in the control group (P < 0.05). These results suggest that treatment of pig bladder with 0.6% trypsin and 5% sodium dodecyl sulfate can effectively remove its cellular components while retaining the extracellular matrix of porcine bladder tissue. This provides a reference value for constructing accelular porcine bladder scaffolds. Figures and Tables | References | Related Articles | Metrics

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Preparation and characterization of magnetic chitosan microspheres Li Li, Ma Li, Li He 2020, 24 (4):  577-582.  doi: 10.3969/j.issn.2095-4344.2207 Abstract ( 324 )   PDF (23955KB) ( 42 )   Save BACKGROUND: As carriers of enzymes, cells and drugs, magnetic polymer microspheres have been widely used in the fields of bioengineering, cytology, and biomedicine. OBJECTIVE: To prepare the magnetic polymer microspheres characterized by small particle size, good dispersion, strong magnetic response, safety, and non-toxicity. METHODS: Magnetic chitosan microspheres were prepared by reverse phase suspension process using Fe3O4 as core, paraffin as dispersed medium, Span-80 as emulsifier, and glutaraldehyde as cross-linking agent. The effects of factors including crosslinking time (0, 20, 40, 60, 80, 100, 120, 150 and 180 minutes), reaction temperature (20→50 °C, 30→60 °C, 40→70 °C, 50→80 °C), the concentration of chitosan (0.01, 0.02, 0.03, 0.04, 0.05 g/mL), Fe3O4/chitosan mass ratio (1∶1, 1∶2, 1∶3, 1∶4), the amount of glutaraldehyde (8-10 mL), the amount of liquid paraffin (40, 60, 80, 100 mL), and stirring speed (0-2 000 r/min) on the properties of magnetic chitosan microspheres. The morphology, particle size, dispersion, and magnetic responsiveness of magnetic chitosan microspheres were characterized. RESULTS AND CONCLUSION: The optimum conditions for preparing magnetic chitosan microspheres were as follows: starting with glutaraldehyde as crosslinking agent, the reaction was performed at 40 °C for 1 hour and then at 70 °C for 120 minutes. The concentration of chitosan was 0.02 g/mL, the mass ratio of Fe3O4/chitosan was 1∶2, the dosage of liquid paraffin was 80 mL, the stirring speed was 1 200 r/min, and the dosage of glutaraldehyde was 8-10 mL. Magnetic chitosan microspheres had strong magnetic properties under the applied magnetic field and had good suspension stability in the natural state. The Fe3O4/chitosan composites were spherical, and the nanoparticles were encapsulated in the microspheres, which were core-shell structure. The surface of the microspheres was smooth and monodisperse. The magnetic chitosan microspheres prepared had a diameter of 1-15 μm, which is beneficial to the dispersion and magnetic separation of the microspheres in the reaction system. Figures and Tables | References | Related Articles | Metrics

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Histocompatibility of poly(L-lactide-co-ε-caprolactone)/cross-linked polyvinylpyrrolidone ureteral stent grafted into the rat bladder Tang Mengmeng, Chen Hechun, Xie Hongchen, Zhang Yu, Tan Xiaoshuang, Sun Yixuan, Huang Yina 2020, 24 (4):  583-588.  doi: 10.3969/j.issn.2095-4344.2214 Abstract ( 377 )   PDF (27350KB) ( 62 )   Save BACKGROUND: With the development of tissue engineering, materials science, and biomechanics, developing new biodegradable ureteral stent has become an issue of concern. The ureteral stent with poly(L-lactide-co-ε-caprolactone)/crosslinked polypyrrolidone was prepared. OBJECTIVE: To explore the histocompatibility of the ureteral stent grafted into the bladder of Sprague-Dawley rats. METHODS: Sixty male Sprague-Dawley rats (provided by Laboratory Animal Center of Sichuan Academy of Traditional Chinese Medicine) were randomly divided into four groups, each group containing 15 rats. The sham operation group was directly sutured after opening a small incision on the outside of the bladder, and no material was implanted. The other three groups were implanted with polyurethane ureteral stent (control group), poly(L-lactide-co-ε-caprolactone)/8% cross-linked polyvinylpyrrolidone ureter stent (experiment group 1), poly(L-lactide ε- caprolactone)/5% cross-linked polyvinylpyrrolidone ureteral stent (experiment group 2) after opening a small incision on the outer side of the bladder, followed by suturing the incision. At 4, 8, and 16 weeks after operation, the local anatomy of the bladder was observed. The histocompatibility of the materials in each group was observed by hematoxylin-eosin staining. The study was approved by the Ethical Committee of Laboratory Animal Analysis and Testing Center of West China School of Public Health, Sichuan University. RESULTS AND CONCLUSION: (1) Gross observation: at 4, 8 and 16 weeks postoperatively, different degrees of chronic inflammation reaction occurred in the control group and experimental group 1. In the experiment group 2, chronic inflammatory reaction appeared at 4 weeks postoperatively. The stone formation rate in the control group and experimental group 1 was significantly higher than that in the sham operation group (P < 0.05) at 4 and 16 weeks postoperatively, which showed no significant difference at 8 weeks postoperatively among groups (P > 0.05). The calculus formation rate in the experimental group 2 was significantly higher than that in the sham operation group only at 4 weeks postoperatively, and had no significant difference at other time points (P > 0.05). (2) Pathological observation: different degrees of foreign body in the outer membrane, inflammatory reaction and diffuse hyperplasia of the mucosa were found in the control group, experimental groups 1 and 2 at different time points postoperatively. There was no significant difference in the rate of diffuse hyperplasia of the mucosa at different time points postoperatively among groups (P > 0.05), but higher than that in the sham operation group (P < 0.05). (3) These results indicate that the calculus formation rate and bladder histological reaction of poly(L-lactide-co-ε-caprolactone)/cross-linked polyvinylpyrrolidone ureter stent are comparable with those of commercial ureteral stents, especially the addition of 5% cross-linked polyvinylpyrrolidone has better histocompatibility. Figures and Tables | References | Related Articles | Metrics

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In vitro biocompatibility of 3D printed polycaprolactone/nano-hydroxyapatite composite scaffold with bone marrow mesenchymal stem cells Hu Chaoran, Qiu Bing, Zhou Zhuxing, Yang Yang, Li Jia 2020, 24 (4):  589-595.  doi: 10.3969/j.issn.2095-4344.1880 Abstract ( 583 )   PDF (26184KB) ( 60 )   Save BACKGROUND: Polycaprolactone/nano-hydroxyapatite composite is a new composite scaffold material prepared based on common bone tissue engineering materials using 3D printing technology. At present, little is reported on the in vitro biocompatibility of the composite material.  OBJECTIVE: To investigate the cytocompatibility of 3D printed polycaprolactone/nano-hydroxyapatite composite scaffolds. METHODS: Polycaprolactone and polycaprolactone/nano-hydroxyapatite composite scaffolds were prepared by 3D printing technology to characterize the microstructure, porosity and mechanical properties of the two materials. Rat bone marrow mesenchymal stem cells were inoculated on the surface of the 3D-printed polycaprolactone and polycaprolactone/nano-hydroxyapatite composite scaffolds. Cell proliferation rate was detected by CCK-8 method. Cell growth on the scaffolds was observed by scanning electron microscopy and Live/Dead cell staining. RESULTS AND CONCLUSION: Two kinds of scaffolds had a three-dimensional network and interconnected structure. The fibers were arranged in a regular order and interlaced. There was no gap on the fiber surface, and the fiber spacing and diameter were relatively uniform. There was no significant difference in the porosity between two kinds of scaffolds (P > 0.05). The elastic modulus of the composite scaffold was higher than that of the simple polycaprolactone scaffold (P < 0.05). There was no significant difference in cell proliferation between two kinds of scaffolds after 1 day of culture. After 4 and 7 days of culture, cell proliferation on the composite scaffold was significantly faster than that on the simple polycaprolactone scaffold (P < 0.05). Live/Dead cell staining showed that both polycaprolactone and polycaprolactone/nano-hydroxyapatite composite scaffolds had good cytocompatibility and high cell viability. A larger number of cells adhered to the polycaprolactone/nano-hydroxyapatite composite scaffolds. Scanning electron microscopy showed that cells grew well on two kinds of scaffolds and distributed on the surface and micropores of the scaffold. The secreted extracellular matrix appeared in filaments and surrounded the cells. These findings suggest that the polycaprolactone/nano-hydroxyapatite composite material prepared by 3D printing technology has abundant pores, exhibit good mechanical properties, and have good cytocompatibility and can be used as a scaffold material for tissue engineering. Figures and Tables | References | Related Articles | Metrics

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Application and research of non-coding RNA in bone tissue engineering with cells and scaffold Huang Hui, Dai Yao, Li Yongsheng, Chen Wei, Tang Fang, Huang Yuting, Zhou Zheng, Liu Hairong 2020, 24 (4):  596-605.  doi: 10.3969/j.issn.2095-4344.1930 Abstract ( 407 )   PDF (63823KB) ( 302 )   Save BACKGROUND: Since non-coding RNAs maintain bone homeostasis through various pathways, applications of non-coding RNAs as bioactive molecules in bone tissue engineering for bone defect repair has become an increasing area of interest. OBJECTIVE: To introduce non-coding RNAs as bioactive molecules in bone tissue engineering. METHODS: A computer-based online search of Web of Science, PubMed, SpringerLink databases was performed by the first author between December 2018 and March 2019 using the search terms “bone tissue engineering, ncRNA (miRNA, siRNA or lncRNA), scaffold, drug delivery system” to retrieve papers published during 2004-2019. A total of 1754 papers were preliminarily retrieved, and 95 of them were eligible for final analysis. RESULTS AND CONCLUSION: Because non-coding RNAs play a key role in osteogenic differentiation, they can be used as important bioactive factors for bone tissue engineering. At present, bone tissue engineering repair methods based on non-coding RNA bioactive factors have become a research hotspot in bone defect repair. There are two major application strategies: (1) The non-coding RNA transcription within the seed cells is purposefully altered and combines with the bone tissue-engineered scaffold to promote bone defect repair. (2) a specifically designed bone engineered scaffold can controllably and purposefully alter the expression of non-coding RNA in the seed cells, which promotes bone defect repair. In addition, the function of more and more non-coding RNAs has been identified in the process of bone regeneration. This shows good application prospects of non-coding RNAs.  Figures and Tables | References | Related Articles | Metrics

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Zn and Mg increase the bioactivity and osteogenic induction of hydroxyapatite biomaterial in bone repair: clinical application and mechanism  Zhang Yanan, Yan Xia, Meng Zengdong 2020, 24 (4):  606-611.  doi: 10.3969/j.issn.2095-4344.1939 Abstract ( 407 )   PDF (37337KB) ( 83 )   Save BACKGROUND: Autologous bones are in high demand in the clinic, but its clinical application is limited because of insufficient sources and donor-site complications. Allogeneic bone and xenogenic bone are also limited because of immune rejection and disease transmission problems. Artificial biomaterials provide an important solution to bone defect repair. OBJECTIVE: To review the latest basic research progress and osteogenic induction mechanism of hydroxyapatite doped with divalent cations such as zinc and magnesium. METHODS: A computer-based online search of Pebmed, Wanfang and CNKI databases was performed to retrieve papers regarding bone repair with hydroxyapatite doped with divalent cations zinc and magnesium with the search terms “Zinc, magnesium, hydroxyapatite, in vivo, in vitro, osteogenic activity” in English and Chinese respectively. RESULTS AND CONCLUSION: Much is reported on the application of degradable active elements Mg and Zn and their application in hydroxyapatite for bone repair. However, most studies focus on metal or alloy implants. Mg-hydroxyapatite and Zn-hydroxyapatite composites are mostly prepared into nano-particles, dense bulk materials or active coatings of biomedical metal mateirals. Little is reported on bone-like porous bone repair materials involving Mg-hydroxyapatite and Zn-hydroxyapatite. At the same time, metal ion materials still face many challenges: First, when specific metals are released locally from stents, implants, or other release devices, their role in cell regulation and cell-cell signaling in healthy and diseased tissues should be known. Second, a large number of in vivoexperiments have confirmed that metal ions can be released from the stent without systemic toxicity, but have carcinogenic effects. Third, there is a need to further understand the mechanism linking biological property improvement and metal ion release.  Figures and Tables | References | Related Articles | Metrics

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Specific bone-targeting nanoscale drug delivery system: advantages and clinical applicability  Xiang Haibin, Li Xinxia, Liang Qiuzhen, Song Xinghua 2020, 24 (4):  612-618.  doi: 10.3969/j.issn.2095-4344.1938 Abstract ( 476 )   PDF (48107KB) ( 83 )   Save BACKGROUND: Specific bone-targeting drug delivery system is very important in the treatment of bone-related diseases. Development of nanotechnology provides a good platform and a new thought for preparation of specific bone-targeting nanoscale drug delivery system. OBJECTIVE: To review the current development and future prospects of specific bone-targeting drug delivery systems. METHODS: A computer-based online search of PubMed, Web of Science, and Medline databases was performed to retrieve studies regarding active targeting drug delivery system and nanoscale drug delivery system published between March 2014 and March 2019 with the search terms “Bone target therapy, Nanoparticles, Drug delivery system”.  RESULTS AND CONCLUSION: The targeting group is an important component of the specific bone-targeting drug delivery system and it determines the targeting efficiency of the drug delivery system. Targeting bone tissue, osteoblasts, osteoblasts, and bone marrow mesenchymal stem cells have their own advantages and disadvantages. Specific bone-targeting nanoscale drug delivery systems have been widely used in various bone diseases, such as metastatic osteoporosis, osteomyelitis, multiple myeloma, osteosarcoma, and bone metastases. Specific bone-targeting drug delivery systems have advantages and challenges. Although many basic studies have shown good results of specific bone-targeting drug delivery systems in vivo, little is reported on successful clinical transformation of bone-targeting groups-modified nanoscale drug delivery systems. Figures and Tables | References | Related Articles | Metrics

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The role and mechanism of graphene and its derivatives-related composites in cartilage repair Tang Jingfeng, Zhang Jun, You Qi, Liu Yi 2020, 24 (4):  619-624.  doi: 10.3969/j.issn.2095-4344.1434 Abstract ( 369 )   PDF (37426KB) ( 81 )   Save BACKGROUND: Graphene-related materials have good biocompatibility and can improve cartilage repair. At the same time, their excellent mechanical strength and electrical conductivity make them promising as cartilage replacement materials, which have been widely used in tissue engineering. OBJECTIVE: To review the general properties, biocompatibility and application of graphene in cartilage tissue engineering and cartilage repair. METHODS: A computer-based online search of CNKI and PubMed databases was performed using the search terms “graphene, tissue engineering, biocompatibility, cartilage” in Chinese and English to search related literatures published between January 2000 and January 2019. Preliminary screening was conducted by reading the titles and abstracts to exclude the literature irrelevant to the theme of the paper. According to inclusion and exclusion criteria, 67 literatures were included in the final analysis. RESULTS AND CONCLUSION: Graphene has good biocompatibility, and has low cytotoxicity to prokaryotic cells and eukaryotic cells, but the cytotoxicity can be further reduced by chemical modification or surface modification, so as not to affect the growth of cells. Graphene and its derivatives can promote the growth and chondrogenic differentiation of human bone marrow mesenchymal stem cells, as well as the proliferation and maturation of chondrocytes, and accelerate the repair of cartilage defects. Due to its mechanical strength and electrical conductivity, graphene can compound biomimetic cartilage material, which is suitable for cartilage tissue engineering. Graphene has several unresolved problems and challenges, but the application potential of graphene-related materials may pave the way for future breakthroughs in tissue engineering research. Figures and Tables | References | Related Articles | Metrics

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Human amniotic membrane, drugs, and growth factors prevent adhesion after repair of tendon injury  Feng Yong, Zhao Yanxu, Zhang Minze 2020, 24 (4):  625-630.  doi: 10.3969/j.issn.2095-4344.1881 Abstract ( 455 )   PDF (32835KB) ( 56 )   Save BACKGROUND: Strong evidence exists that tendon adhesion occurs after tendon repair. OBJECTIVE: To review the advance in research on the prevention of tendon adhesion in terms of human amniotic membrane, drugs and growth factor. METHODS: A computer-based online search of Wanfang, CNKI, and Medline databases was performed to search papers regarding prevention of adhesion after tendon injury published between January 2000 and April 2019 with the search terms “tendon injury, tendon adhesions, drug, human amniotic membrane, growth factor” in English and Chinese. Papers recently published in high-impact journals in the same research field were selected. Fifty papers were included in the final analysis. RESULTS AND CONCLUSION: Amniotic membrane and acellular amniotic membrane are effective in preventing tendon adhesion. Drugs can work in many ways to achieve the purpose of preventing adhesion, and drugs exhibit better efficacy after combined application with sustained-release carrier. Most growth factors not only promote tendon healing but also promote adhesion formation. The formation of tendon adhesion can be reduced by adjusting the concentration of growth factors in the lesion site.  Figures and Tables | References | Related Articles | Metrics

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Chitosan-based polysaccharide biomaterial for prevention and treatment of oral diseases Liu Haiyan, Hu Yang, Wu Xiuping, Pan Haobo, Jing Xuan 2020, 24 (4):  631-636.  doi: 10.3969/j.issn.2095-4344.1948 Abstract ( 498 )   PDF (37432KB) ( 242 )   Save BACKGROUND: Polysaccharide-based biomaterials are hydrophilic and can promote cell adhesion, proliferation and differentiation. They can not only effectively prevent against oral diseases, but also promote the regeneration of periodontal ligament, enamel and alveolar bone. OBJECTIVE: To review the application of chitosan-based polysaccharide biomaterial in many oral diseases. METHODS: A computer-based online search of PubMed and CNKI databases was performed to retrieve papers regarding application of chitosan-based polysaccharide biomaterial in oral diseases with the search terms “polysaccharide (chitosan or hyaluronic acid or cellulose) and oral disease” in Chinese and English. RESULTS AND CONCLUSION: Chitosan-based polysaccharide biomaterial can be used in periodontal, oral and maxillofacial systems, aesthetic restoration, orthodontics and other fields because chitosan has aminoglucan-like structure and the biological functions of cellulose and collagen, and possesses good biocompatibility. In the early stage of the disease, polysaccharide substance can prevent the occurrence of oral diseases and inhibit the accumulation of plaque microorganisms. During the repair period of the disease, polysaccharide substance itself can promote cell proliferation and differentiation, and has a good antibacterial effect. With the help of the specific efficacy of polysaccharide biomaterials, polysaccharide can effectively exert adhesion, antibacterial and regeneration effects. In addition, polysaccharides can also be digested to monosaccharides in vivo, which is good for tissue repair. In the future therapeutic field, the degradability, biocompatibility, easy availability, specific network structure, surface charge and other characteristics of the polysaccharide can be better utilized to expand the application range. Figures and Tables | References | Related Articles | Metrics

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Application and prospects of 3D printing technology in dental manufacturing Yao Lu, Hu Peixin, Liu Wu, Lü Qitao, Nie Zilin, He Zhengdi 2020, 24 (4):  637-642.  doi: 10.3969/j.issn.2095-4344.1929 Abstract ( 495 )   PDF (35198KB) ( 64 )   Save BACKGROUND: In the case of tooth defect or missing, the treatment should be achieved by making a personalized prosthesis. Traditional manufacturing process is time-consuming, costly and accurate. After the introduction of 3D printing technology into dental manufacture, the manufacturing efficiency and quality can be improved to a certain extent. OBJECTIVE: To introduce the application of 3D printing technology in dental manufacture, discuss the bottleneck in recent application, and guide the development of 3D printing technology in dental manufacture. METHODS: The authors used the search times "3D printing, metal implant, dental manufacturing, dental restorations” to search Web of Science, Wanfang, CNKI databases in English and Chinese separately to search papers published during 1980-2019. 261 papers were preliminarily retrieved and 60 of them were included in the final analysis. RESULTS AND CONCLUSION: 3D printing dental mold, digital implant guide plate and wax pattern have been widely used in dental manufacture. 3D printing technology has been widely used in dental manufacture. The most widely used six processes are stereo lithography appearance, laminated object manufacturing, fused deposition modeling, selective laser sintering, selective laser melting, and inkjet printing. There are some technical bottlenecks in the application of 3D printing technology in the field of dental manufacturing. After breaking through technology bottlenecks, 3D printing will be more useful in the field of dental manufacturing in the future.  Figures and Tables | References | Related Articles | Metrics

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Antineoplastic mechanism of antimicrobial peptides: selective membrane destruction and non-membrane dissolution  Gong Lei, Zhang Xi 2020, 24 (4):  643-649.  doi: 10.3969/j.issn.2095-4344.2203 Abstract ( 405 )   PDF (40358KB) ( 63 )   Save BACKGROUND: Antimicrobial peptides, an extract from nature, are a basic component of host immunity that make toxic effect on highly proliferative cells. They have attracted extensive attention of scientists. The understanding of the antineoplastic mechanism of antimicrobial peptides can contribute to its application in clinical practice.   OBJECTIVE: To summarize the research advances in antineoplastic mechanism of antimicrobial peptides. METHODS: The first author conducted a computer-based retrieval of PubMed, Springerlink, Web of Science, and ScienceDirect databases for relevant articles published from January 2015 to May 2019. The keywords were “antimicrobial, peptide, antitumor mechanisms, antitumor activity and anti-neoplastic”. The articles concerning antineoplastic mechanism of antimicrobial peptides and research progress were selected. RESULTS AND CONCLUSION: Cationic antimicrobial peptides synthesized by ribosomes and the host defense peptides can interact with the membrane of bacteria, which showed a broad-spectrum antimicrobial activity. Compared with normal cells, the proportion of phosphatidylserine on the surface of cancer cells, which is negatively charged, is increased dramatically. As a result, the cationic amphiphilic peptides are good candidate for the antineoplastic drugs, and possess a high selectivity. There are two major antitumor mechanism of antimicrobial peptides, which are selective membrane destruction and non-membrane dissolution (α-defensin-1 and lactoferrin B). The clinical application of antimicrobial peptides against tumors is mainly restricted by their stability and the ways to administration. By optimizing its structure and drug delivery systems, these antimicrobial peptides will play a critical role in the cancer treatment. Figures and Tables | References | Related Articles | Metrics

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Bone filling bag vertebroplasty and percutaneous kyphoplasty for the treatment of thoracolumbar osteoporotic compression fractures: a meta-analysis of improving Cobb angle and reducing bone cement leakage Li Kaiming, Wang Shangquan, Li Linghui, Zhu Liguo, Zhang Qing, Xie Rui 2020, 24 (4):  650-656.  doi: 10.3969/j.issn.2095-4344.1444 Abstract ( 514 )   PDF (28904KB) ( 44 )   Save BACKGROUND: It remains disputed whether bone filling bag vertebroplasty and percutaneous kyphoplasty have different treatment efficacy in the treatment of thoracolumbar osteoporotic compression fractures. OBJECTIVE: To systematically analyze the efficacy and safety of bone filling bag vertebroplasty and percutaneous kyphoplasty in the treatment of thoracolumbar osteoporotic compression fractures. METHODS: A computer-based online search of CNKI, Wanfang, VIP, CBM, EMBASE, MEDLINE, and Cochrane libraries was performed to retrieve randomized controlled trial studies regarding bone filling bag vertebroplasty and percutaneous kyphoplasty in the treatment of thoracolumbar osteoporotic compression fractures published before February 2019.Two researchers independently conducted literature screening and data extraction. According to the Cochrane Collaboration Network standard, the quality of the randomized controlled trial studies was evaluated one by one. The studies that met the inclusion criteria were analyzed using the RevMan5.3 software. RESULTS AND CONCLUSION: Six randomized controlled trial studies were included. A total of 517 patients were included in the final analysis. Among them, 257 patients received bone filling bag vertebroplasty and 260 patients received percutaneous kyphoplasty. Meta-analysis showed that there were no significant differences in postoperative Visual Analogy Score (MD=0.00, 95%CI: -0.09-0.10, P=0.94), vertebral height recovery (SMD=0.11, 95%CI: -0.26-0.48, P=0.57), and Oswestry Disability Index (MD=1.47, 95%CI: -0.45-3.39, P=0.13) between these two surgical procedures. But postoperative Cobb angle (MD=-1.08, 95%CI: -1.47 to -0.70, P < 0.000 01) and bone cement leakage rate (RR=0.24, 95%CI: 0.13-0.45, P < 0.000 01) were significantly different between these two surgical procedures. Bone filling bag vertebroplasty exhibits significant advantages in improving postoperative Cobb angle and reducing bone cement over percutaneous kyphoplasty. These two surgical procedures have similar clinical outcomes such as postoperative Visual Analogy Score, vertebral height recovery, and Oswestry Disability Index. Therefore, a large number of high-quality multicenter randomized controlled trials are needed to provide more evidence.  Figures and Tables | References | Related Articles | Metrics