15 extracted premolars were selected and randomly divided into 3 groups, with 5 in each group. MANI TF-13 bur、TR13-EF bur and the dental pneumatic ultrasonic hand-piece were respectively used to dispose the shoulder. 15 Zirconium dioxide full crowns were made. The shoulder marginal microleakage was observed by staining method. Dental pneumatic ultrasonic hand-piece showed the best anti-mic-roleakage effect in shoulder refinement.

Objective To describe the clinical manifestation of the chronic atlantoaxial rotatory dislocation (AARD) with C1,2 lateral facets locked,and explore the effect of the operation combined with anterior retropharyngeal approach and posterior approach.Methods Data of 8 patients with chronic AARD with C1,2 lateral facet locked who had undergone open reduction with the anterior retropharyngeal approach and C 1,2 transpedicular screw fixation with autologous iliac bone graft from Oct.2010 to Jun.2013 were retrospectively analyzed.There were 4 males and 4 females with an average age of 31 years old (range,11-57 years old).The intervals from onset to diagnosis were from 29 to 180 days and the mean time was 70.6 days.5 cases were chronic AARD with right C1,2 lateral facets locked and 3 with left C1,2 lateral facets locked.Reduction was failed to obtain by traction for two to four weeks.Subsequently,after open reduction with the anterior retropharyngeal approach,the patients were performed C 1,2 transpedicular screw fixation with autologous iliac bone graft for one stage or two.Results 1 patient underwent open reduction with the anterior retropharyngeal approach in stage one and C1,2 transpedicular screw fixation in stage two because of an overall severe condition,and the other patients did anterior and posterior operation in one stage.The average operation time was 205 min (range,160-260 min).The mean blood loss was 210 ml (range,100-300 ml).There were no operation complications except one young girl reflected pain in autologous iliac donated area,and pain relieved when taking non-steroidal anti-inflammatory by oral for one week.All patients had been followed up for a mean period of 14.8 months (range,5-37 months).Three-dimensional computed tomography revealed C1,2 arthrodesis bone graft fusion from two to four months and the average was 3.1 months.Neither recurrence of symptoms nor dislocation was observed at the latest follow-up.Conclusion Open reduction through the anterior retropharyngeal approach with C1,2 transpedicular screw fixation is an effective treatment strategy for chronical AARD with C1,2 lateral facets locked,which reduces surgical complications with less operation difficulty.

Objective:To study the influences of sucrose,citric acid and sodium bicarbonate on the adhesion of 3 kinds of adhesives.Methods:60 extracted tooth and 60 zirconia blocks (3 mm × 3 mm × 3 mm) were randomly divided into 3 groups (n =20),namely PULPDENT group,3M ESPE RelyxTM Veneer group and RelyxTM Luting group.Then,the samples of each group fell into 4 subgroups(n=5),namely subgroup A for artificial saliva,subgroup B for 10％ sucrose,subgroup C for 0.2％ citric acid,and subgroup D for 0.03 ％ sodium bicarbonate.After completing the adhesion of the specimens with corresponding adhesives,the specimens of subgroups A,B,C and D were submerged into artificial saliva(the control),sucrose,citric acid and sodium bicarbonate solutions for 2 times/day and 5 min/time,respectively.For the rest of time,all the specimens were submerged in artificial saliva.3 months later,shear bond strength of the specimens was tested,the fracture surface was observed under SEM,20 × microscope,and the fracture model was observed by stereoscopic microscope.SPSS 17.0 software was adopted for statistical analysis of the data.Results:The bond strength of PULPDENT,3M ESPE RelyxTM Veneer groups were higher than that of RelyxTM Luting group(P ＜ 0.05);the bond strength of subgroups B,C and D was lower than that of subgroup A(P ＜0.05);and the difference between the remaining groups was not statistically significant(P ＞0.05).SEM observation displayed that in group RelyxTM Luting,subgroups B,C and D showed increased crack depth,width and length when compared with subgroup A;there was no obvious difference between the remaining groups and the control group;in groups PULPENT,3M ESPE RelyxTM Veneer and RelyxTM Luting,all samples in their subgroups showed interface failure.Conclusion:Compared with PULPDENT and 3M ESPE RelyxTM Veneer adhesive,RelyxTM Luting is more susceptible to the influence of sucrose,citric acid and sodium bicarbonate,so it is not suitable for bonding zirconia blocks.

Malaria is one of the major diseases threatening the lives of people in Africa. Over the past decade, China has provided anti-malaria assistance to Africa. In November 2007, fast control malaria team of Guangzhou University of Chinese Medicine cooperated with the Comoros health authority. In Moheli Island of the Comoros, the anti-malaria team adopted a new strategy of Mass Drug Administration (MDA) and active intervention. They established an effective anti-malaria system and reporting system, as well as a local anti-malaria team. Furthermore, they treated patients with malaria in Moheli Island and implemended health education in local people. In a very short time, they have achieved remarkable results. This paper summarized the experiences of the project in order to provide useful reference for China to better carry out anti-malaria action in Africa and expand foreign health assistance.

Objective To compare 2 kinds of artificial dermis Lando(R) versus Pelnac(R) combined with induced membrane technique in the treatment of composite trauma in rabbit bilateral femurs.Methods Twenty-seven male rabbits,weighing from 1.92 kg to 2.21 kg (average,2.04 kg),were used in the experiments.After models of composite trauma were created in the bilateral femurs of all the rabbits,the bilateral femurs of 9 random rabbits were subjected to the treatment of artificial dermis Lando(R) plus induced membrane (Lando(R) group),the bilateral femurs of another 9 random rabbits to the treatment of artificial dermis Pelnac(R) plus induced membrane (Pelnac(R) group),the left femur of the remaining 9 rabbits to the treatment of induced membrane (control group) and the right femur of the remaining 9 rabbits to no treatment (sham operation group).Three rabbits from each group (the same for the control and sham operation groups) were randomly sacrificed at 2,4 and 6 weeks after operation.Samples from the operation sites were taken for gross observation of the induced membrane and observation of the microstructure of the membrane by conventional hematoxylin-eosin staining.In addition,the microvessel density (MVD) was counted under microscopy taking CD34 immunohistochemistry as the standard.The data were statistically analyzed.Results The collagen sponge layer was completely degraded 2 weeks after operation in the Lando(R) group but not in the Pelnac(R) group.The MVD [(0.90 ± 0.55)/HPF] in the Lando(R) group was significantly greater than that in the Pelnac(R) group [(0.28 ± 0.13)/HPF] (P ＜ 0.05).The collagen sponge layer was degraded 4 weeks after operation in the Lando(R) and Pelnac(R) groups and there was no significant difference between the 2 groups in MVD [(3.61 ± 1.31)/HPF versus (4.34 ± 0.77)/HPF] (P ＞ 0.05).At 6 weeks postoperatively,the MVD [(4.97 ±0.76)/HPF] in the Lando(R) group was significantly smaller than that in the Pelnac(R) group [(7.06 ± 1.03)/HPF] (P ＜ 0.05).At 2 weeks after operation,the MVD was (0.11 ±0.19)/HPF in the control group and the sham operation group,showing a significant difference compared with the Lando(R) group (P ＜ 0.05) but no significant difference compared with the Pelnac(R) group (P ＞ 0.05).The MVD at 4 and 6 weeks after operation in the control and the sham operation groups were all significantly different from those in the Lando(R) and the Pelnac(R) groups (P ＜ 0.05).Conclusions In the treatment of composite trauma in rabbits,the 2 kinds of artificial dermis combined with the induction membrane technique can lead to formation of induced membrane structure,providing a new alternative treatment for patients with bone and soft tissue defects caused by various causes in the clinic.The Lando(R) artificial dermis may accelerate the vascularization of induced membrane at 2 weeks while the Pelnac(R) may accelerate the vaseularization at 4 and 6 weeks.

Objective:To analyze the perfusion characteristics of choroidal metastasis using contrast-enhanced ultrasound, and compare with choroidal hemangioma.Methods:This was a retrospective study.From January 2016 to February 2018 in Beijing Tongren Hospital, a total of 21 eyes from 21 patients who were clinically diagnosed as choroidal metastasis were included as the choroidal metastasis group and 46 eyes from 46 patients who were diagnosed as choroidal hemangioma during the same period were included as the choroidal hemangioma group. All patients underwent contrast-enhanced ultrasound examination, and Sonoliver was used to obtain the data on quantitative parameters of the tumor and the adjacent normal orbital tissues, including maximum of intensity (IMAX), rise time (RT), time to peak (TTP), and mean transit time (mTT). The quantitative parameters between choroidal metastasis and normal orbital tissues were compared. And the quantitative parameters between choroidal metastasis and choroidal hemangioma were compared. The receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance.Results:The IMAX of choroidal metastasis was significantly higher than that of normal orbital tissues, while RT, TTP and mTT were significantly shorter than these of normal orbital tissues (all P<0.01). The IMAX of choroidal metastasis was lower than that of choroidal hemangioma, and RT, TTP and mTT were shorter than choroidal hemangioma (all P<0.01). The ROC curve analysis showed that area under curves of the IMAX, RT, TTP and mTT were 0.775 (95% CI=0.666-0.884), 0.970 (95% CI=0.896-0.996), 0.729 (95% CI=0.607-0.831) and 0.992 (95% CI=0.931-1.000) respectively. The sensitivities were 71.7%, 95.7%, 76.1% and 95.7%, and the specificities were 85.7%, 90.5%, 66.7% and 95.2%, respectively. Conclusions:Contrast-enhanced ultrasound can reflect the differences in perfusion characteristics between choroidal metastasis and choroidal hemangioma. RT and mTT are useful parameters in differential diagnosis between the two types of tumors.

Humans ; COVID-19 ; HIV Infections/drug therapy* ; Risk Factors

Objective:To analyze the incidence and epidemiological characteristics of traumatic spinal cord injury in China in 2018.Methods:Multi-stage stratified cluster sampling was used to randomly select hospitals capable of treating patients with spinal cord injury from 3 regions，9 provinces and 27 cities in China to retrospectively investigate eligible patients with traumatic spinal cord injury admitted in 2018. National and regional incidence rates were calculated. The data of cause of injury，injury level，severity of injury，segment and type of fracture，complications，death and other data were collected by medical record questionnaire，and analyzed according to geographical region，age and gender.Results:Medical records of 4，134 patients were included in this study，with a male-to-female ratio of 2.99∶1. The incidence of traumatic spinal cord injury in China in 2018 was 50.484 / 1 million （95% CI 50.122-50.846）. The highest incidence in the Eastern region was 53.791 / 1 million （95% CI 53.217-54.365）. In the whole country，the main causes of injury were high falls （29.58%），as well as in the Western region （40.68%），while the main causes of injury in the Eastern and Central regions were traffic injuries （31.22%，30.10%）. The main injury level was cervical spinal cord in the whole country （64.49%），and the proportion of cervical spinal cord injury in the Central region was the highest （74.68%），and the proportion of lumbosacral spinal cord injury in the Western region was the highest （32.30%）. The highest proportion of degree of injury was incomplete quadriplegia （55.20%），and the distribution pattern was the same in each region. A total of 65.87% of the patients were complicated with fracture or dislocation，77.95% in the Western region and only 54.77% in the Central region. In the whole country，the head was the main combined injury （37.87%），as well as in the Eastern and Central regions，while the proportion of chest combined injury in the Western region was the highest （38.57%）. A total of 32.90% of the patients were complicated with respiratory complications. There were 23 patients （0.56%） died in hospital，of which 17（73.91%） died of respiratory dysfunction. Conclusions:The Eastern region of China has a high incidence of traumatic spinal cord injury. Other epidemiological features include high fall as the main cause of injury cervical spinal cord injury as the main injury level，incomplete quadriplegia as the main degree of injury，head as the main combined injury，and respiratory complications as the main complication.

According to the pathological characteristics of symptomatic chronic thoracic and lumbar osteoporotic vertebral fracture (SCOVF), the different clinical treatment methods are selected, including vertebral augmentation, anterior-posterior fixation and fusion, posterior decompression fixation and fusion, and posterior correction osteotomy. However, there is still a lack of a unified understanding on how to choose appropriate treatment method for SCOVF. In order to reflect the new treatment concept and the evidence-based medicine progress of SCOVF in a timely manner and standardize its treatment, the clinical guideline for surgical treatment of SCOVF is formulated in compliance with the principle of scientificity, practicability and advancement and based on the level of evidence-based medicine.

Ankylosing spondylitis (AS) combined with spinal fractures with thoracic and lumbar fracture as the most common type shows characteristics of unstable fracture, high incidence of nerve injury, high mortality and high disability rate. The diagnosis may be missed because it is mostly caused by low-energy injury, when spinal rigidity and osteoporosis have a great impact on the accuracy of imaging examination. At the same time, the treatment choices are controversial, with no relevant specifications. Non-operative treatments can easily lead to bone nonunion, pseudoarthrosis and delayed nerve injury, while surgeries may be failed due to internal fixation failure. At present, there are no evidence-based guidelines for the diagnosis and treatment of AS combined with thoracic and lumbar fracture. In this context, the Spinal Trauma Academic Group of Orthopedics Branch of Chinese Medical Doctor Association organized experts to formulate the Clinical guideline for the diagnosis and treatment of adult ankylosing spondylitis combined with thoracolumbar fracture ( version 2023) by following the principles of evidence-based medicine and systematically review related literatures. Ten recommendations on the diagnosis, imaging evaluation, classification and treatment of AS combined with thoracic and lumbar fracture were put forward, aiming to standardize the clinical diagnosis and treatment of such disorder.