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BACKGROUND:At present,nanocomposite gelatin methacryloyl hydrogels have been extensively studied in bone tissue engineering. OBJECTIVE:To review the latest research progress of nanocomposite gelatin methacryloyl hydrogels,and introduce the application of nanocomposite gelatin methacryloyl hydrogels in different bone defect environments. METHODS:The computer retrieval was conducted for relevant literature published in CNKI,WanFang,PubMed,and Web of Science databases from 2016 to 2023.The Chinese and English search terms were"gelatin,methacryl*,nano*,bone,bone tissue engineering,bone regeneration,osteogenesis". RESULTS AND CONCLUSION:(1)Up to now,inorganic nanomaterials,organic nanomaterials and organic-inorganic hybrid nanomaterials are the main nanomaterials used as fillers for gelatin methacryloyl.(2)Inorganic nanomaterials enhance the mechanical strength of gelatin methacryloyl,improve its thixotropic properties and degradation rate,and realize the antibacterial,osteogenic,immunoregulatory,angiogenic and other functions of gelatin methacryloyl hydrogel through its surface charge regulation,drug/factor loading,metal ion self-degradation release,etc.(3)Organic nanomaterial and organic-inorganic hybrid nanomaterial composite gelatin methacryloyl hydrogel are two emerging materials.At present,there are relatively few studies,but from the published research,compared with inorganic nanomaterial gelatin methacryloyl hydrogel,organic nanomaterial gelatin methacryloyl hydrogel has better biocompatibility and drug-loading performance.The interaction between nano phase and organic polymer phase is stronger,and the dispersion of nano particles is better.(4)Organic-inorganic hybrid nanomaterial composite gelatin methacryloyl combines the advantages of the previous two,and has better controllability of metal ion release,which proves great research potential.(5)Nanomaterials can enhance the antibacterial,immune regulation,osteogenesis and other biological properties of gelatin methacryloyl,so as to promote bone regeneration in the complex bone defect microenvironment,such as infected bone defect,diabetes,osteosarcoma resection and so on.However,the relevant research of nanocomposite gelatin methacryloyl hydrogel in bone repair is still limited to animal experiments.Further safety testing and clinical studies are still needed.
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Cholangiocarcinoma (CCA) is the most recurrent malignant tumor found in the biliary system. It originates from the bile duct epithelial cells characterized by easy metastasis, high intermittent rate, and poor prognosis. Acetaldehyde dehydrogenase 1 (ALDH1), a marker of cancer stem cells, the levels of which are particularly elevated in various of malignant tumors. Additionally, the increased ALDH1 levels are closely related to the degree and prognosis of malignant tumors. This study reviewed the mechanisms underlying the changes in ALDH1 levels in CCA.
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BACKGROUND: Hepatocellular carcinoma (HCC) is the fifth most frequently diagnosed malignancy and the third leading cause of cancer death globally. T cells are significantly correlated with the progression, therapy and prognosis of cancer. Limited systematic studies regarding the role of T-cell-related markers in HCC have been performed. METHODS: T-cell markers were identified with single-cell RNA sequencing (scRNA-seq) data from the GEO database. A prognostic signature was developed with the LASSO algorithm in the TCGA cohort and verified in the GSE14520 cohort. Another three eligible immunotherapy datasets, GSE91061, PRJEB25780 and IMigor210, were used to verify the role of the risk score in the immunotherapy response. RESULTS: With 181 T-cell markers identified by scRNA-seq analysis, a 13 T-cell-related gene-based prognostic signature (TRPS) was developed for prognostic prediction, which divided HCC patients into high-risk and low-risk groups according to overall survival, with AUCs of 1 year, 3 years, and 5 years of 0.807, 0.752, and 0.708, respectively. TRPS had the highest C-index compared with the other 10 established prognostic signatures, suggesting a better performance of TRPS in predicting the prognosis of HCC. More importantly, the TRPS risk score was closely correlated with the TIDE score and immunophenoscore. The high-risk score patients had a higher percentage of SD/PD, and CR/PR occurred more frequently in patients with low TRPS-related risk scores in the IMigor210, PRJEB25780 and GSE91061 cohorts. We also constructed a nomogram based on the TRPS, which had high potential for clinical application. CONCLUSION: Our study proposed a novel TRPS for HCC patients, and the TRPS could effectively indicate the prognosis of HCC. It also served as a predictor for immunotherapy.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Pronóstico , Transcriptoma , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Linfocitos T , InmunoterapiaRESUMEN
BACKGROUND: The actin filament-associated protein (AFAP) family genes include AFAP1/AFAP-110, AFAP1L1 and AFAP1L2/XB130. Increasing evidence indicates these three AFAP family members participate in tumor progression, but their clinical significance and molecular mechanisms in gastric cancer (GC) remain unclear. METHODS: We first analyzed expression of AFAP family genes using public datasets and verified the results. The clinical significance of AFAP family genes in GC patients was also analyzed. In vitro and in vivo experiments were applied to explore the function of AFAP1L1. Enrichment analysis was used to explore potential molecular mechanisms. We then performed additional experiments, such as cell adhesion assay, co-immunoprecipitation and so on to confirm the downstream molecular mechanisms of AFAP1L1. RESULTS: Public data analyses and our verification both showed AFAP1L1 was the only AFAP family members that was significantly upregulated in GC compared with normal gastric tissues. Besides, only AFAP1L1 could predict poor prognosis and act as an independent risk factor for GC patients. In addition, AFAP1L1 promotes GC cells proliferation, migration, invasion in vitro and tumor growth, metastasis in vivo by inducing epithelial-to-mesenchymal transition (EMT). In terms of mechanism, AFAP1L1 interacts with VAV guanine nucleotide exchange factor 2 (VAV2) to activate Rho family GTPases CDC42, which finally promotes expression of integrin subunit alpha 5 (ITGA5) and activation of integrin signaling pathway. CONCLUSION: AFAP1L1 promotes GC progression by inducing EMT through VAV2-mediated activation of CDC42 and ITGA5 signaling pathway, indicating AFAP1L1 may be a promising prognostic biomarker and therapeutic target for GC patients.
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Neoplasias Gástricas , Humanos , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Transición Epitelial-Mesenquimal/genética , Integrinas/metabolismo , Proteínas de Microfilamentos/genética , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-vav/genética , Proteínas Proto-Oncogénicas c-vav/metabolismo , Transducción de Señal , Neoplasias Gástricas/patologíaRESUMEN
Objective: To study the long-term morphological stability of three-dimensional (3D) printed photosensitive resin dental models under natural light and dark conditions. Methods: Eighty sets of resin dental models were made by the desktop 3D printer from one digital standard model set, and randomly divided into two groups, namely natural light group (40 sets) and dark group (40 sets). All resin models were stored in sealed bags, with 4 model sets from each group randomly collected after 1, 3, 5, 7, 14, 21, 28, 40, 60, or 90 days of storage and 3D scanned using an optical model scanner. The root-mean-square error (RMSE) was calculated to represent the mean deviation of the difference between the digital standard model and the scanned resin model. Meanwhile, three linear indexes (the width between the canines, the width between the first molars, and the arch length) of the resin dental model were measured and compared with the corresponding values of the standard model. RMSE and the linear measurements between the digital standard model and the scanned resin models were compared between the natural light group and the dark group and among models from different time points. Results: Compared with the digital standard model, the RMSE values of 96.9% (155/160) resin dental models were less than 0.1 mm within 90-day storage. Also, at the same time point, there was no significant difference in the RMSE between the natural light group and the dark group (P>0.05). 75.0% (360/480) of the absolute values of the linear differences (differences in inter-canine width, intra-molar width, and arch length between the digital standard model and the scanned resin model) were within 0.2 mm, and about 0.1% (3/480) of the linear differences were greater than 0.5 mm, and all of the linear differences were within 0.6 mm. Conclusions: 3D-printed resin dental models can be stored stably under natural light and dark conditions for a long time.
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Explore the feasibility and effectiveness of accepting mind mapping combined with problem-based learning (PBL) teaching method in the standardized training of emergency surgery residents in the multi-disciplinary team (MDT) model of emergency trauma. Eighty-nine doctors under training who rotated in the Department of Emergency Surgery of the First Affiliated Hospital of Anhui Medical University from January 2021 to January 2022 were selected as the study subjects, and randomly divided into a group receiving mind mapping combined with PBL teaching and a group receiving traditional lecture-based learning teaching. Mini-clinical evaluation exercise (Mini-CEX), direct observation of procedural skills (DOPS), teaching adherence, and satisfaction assessments were completed at the time of discharge from the department. There were no significant differences between the observation and control group trainees in terms of gender, age, education, and entry grades. Both groups of doctors were better able to participate in their respective teaching modes and made significant progress. The participants in the observation group had significantly higher Mini-CEX, DOPS, and teaching satisfaction scores than the control group (Pâ <â .05). Under the MDT model of emergency trauma, the combination of mind mapping and PBL teaching can improve the comprehensive clinical ability of the trainees more than participating in the traditional lecture-based learning teaching, which is worth promoting and implementing in the clinical standardized training.
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Competencia Clínica , Aprendizaje Basado en Problemas , Evaluación Educacional/métodos , Humanos , AprendizajeAsunto(s)
Aprendizaje , Microondas , Hipocampo , Aprendizaje por Laberinto , Memoria , Microondas/efectos adversosRESUMEN
We have previously shown trichloroethylene (TCE) induced immune liver injury, and TNF-α/TNFR1 pathway as a probably mechanism underlying the immune damage, but the pathogenic mechanism is still unclear. The study aims to investigate whether TNF-α and its receptors regulate Kupffer cell polarization and downstream inflammation signaling pathways during TCE sensitization, to clarify the mechanism of TCE-mediated immune liver injury. 6-8 weeks old SPF BALB/c female mice were used to establish a TCE sensitization model. We found that in the TCE sensitization positive group, liver injury was aggravated, Kupffer cells activated and polarized to M1 type. The expression of M1 Kupffer cell marker proteins CD11c and CD16/32 increased in the TCE positive group, so did TNF-α and TNFR1 in liver. The expression of P-IKK protein, PP65 protein and P-STAT3 protein increased in the TCE sensitization positive group, and the downstream inflammatory factors IL-1ß and IL-6 also increased in the TCE sensitization positive group. After using the TNFR1 inhibitor R7050, we found that M1 Kupffer cell polarization, TNF-α expression, signal pathway expression and inflammatory factors IL-1ß and IL-6 expression declined, and the liver damage relieved. Briefly, the use of R7050 to inhibit TNF-α/TNFR1 changing the polarization of liver M1 Kupffer cell, thereby inhibiting the activation of related downstream signaling pathways and reducing the secretion of inflammatory factors. TNF-α/TNFR1 regulates the polarization of M1 Kupffer cells inflammatory play an important role in liver immune damage.
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OBJECTIVE: To study the roles of AT1R, PLC-ß1, CaM and other related signal molecules in the formation and development of hepatocellular carcinoma (HCC) and their correlation. METHODS: ELISA and immunohistochemistry were used to analyze the expressions of target proteins in serum and liver tissue of HCC patients, and the correlation between AT1R, PLC-ß1 and CaM and postoperative survival status of patients was followed up and determined. CCK-8 method was used to screen the doses of Ang II and candesartan sensitive to HepG2 and HCCLM3 cells. Transwell experiment was used to observe the effects of different drugs on the migration and invasion activity of HCC cells. Meanwhile, flow cytometry and Western blot were used to detect the expression levels of AT1R, PLC-ß1 and CaM in the cells. Then PLC-ß1 siRNA was selected to transfect HCC cells, so as to further clarify the mechanism of the above signal proteins. HepG2 cells were inoculated under the hepatic capsule of mice to induce the formation of HCC in situ. Ang II and candesartan were used to stimulate HCC mice to observe the difference in liver appearance and measure the liver index. Finally, ELISA and immunofluorescence experiments were selected to analyze the levels of target proteins in mouse serum and liver tissue. RESULTS: The expression levels of target proteins in serum and liver tissue of HCC patients were significantly increased, and the postoperative survival time of patients with high expression of AT1R, PLC-ß1 or CaM was obviously shortened. Ang II and candesartan could significantly promote and inhibit the motility of HCC cells, and had different effects on the levels of AT1R, PLC-ß1 and CaM in cells. However, in hepatocellular carcinoma cells transfected with PLC-ß1 siRNA, the intervention ability of drugs was obviously weakened. Ang II could significantly promote the formation and progression of mouse HCC, while candesartan had the opposite effect. Meanwhile, medications could affect the expressions of target proteins in mouse serum and liver tissue. CONCLUSION: AT1R, PLC-ß1 and CaM may be risk factors affecting the formation and prognosis of HCC, and the PLC-ß1/CaM signaling pathway mediated by AT1R is an important way to regulate the migration and invasion activity of HCC cells.
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OBJECTIVE: To compare the efficacy and safety of a combination therapy of biologics and immunosuppressants with biological monotherapy in inflammatory bowel disease (IBD) in a systematic review and meta-analysis. METHODS: Eligible randomized controlled trials (RCTs) on the comparison of the efficacy and safety of biologics and immunomodulators with biological monotherapy were identified from the EMBASE, PubMed and the Cochrane Library databases published up to 1 May 2020. Raw data were extracted, pooled relative risk (RR) and 95% confidence interval (CI) was calculated, the fixed-effect and inverse variance models were used. Funnel plots were performed to analyze publication bias. RESULTS: Twelve RCTs were eligible for analysis. Overall, there was statistically a benefit for combination treatment over biologic monotherapy (IFX/ADA) in inducing clinical remission and preventing relapse in patients with IBD (RR 0.89, 95% CI 0.80-0.98). Moreover, the combination therapy was superior to biological monotherapy for active CD (RR 0.83, 95% CI 0.73-0.94). Also, there were significant benefits for combination therapy in the subgroup treated with infliximab (IFX) (RR 0.83, 95% CI 0.70-0.97). CONCLUSIONS: Combination therapy has slight benefits in inducing clinical remission in active CD compared with biological monotherapy. Patients with IBD who receive therapy with IFX and immunomodulator also have a mild advantage in comparison with those treated with IFX monotherapy.
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Productos Biológicos/uso terapéutico , Inmunosupresores/uso terapéutico , Enfermedades Inflamatorias del Intestino , Humanos , Factores Inmunológicos/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Infliximab/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Inducción de Remisión , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/antagonistas & inhibidoresRESUMEN
Osteocalcin (OCN) was the most abundant noncollagen protein and considered as an endocrine factor. However, the functions of Undercarboxylated osteocalcin (ucOCN) on osteoclast and bone resorption are not well understood. In the present study, preosteoclast RAW264.7 cells and bone marrow mononuclear cells (BMMs) were treated with ucOCN purified from prokaryotic bacteria. Our results showed that ucOCN attenuated the proliferation of RAW264.7 cells with a concentration dependant manner by MTS assay. Scrape wounding assay revealed the decreased motility of RAW264.7 cells after ucOCN treatment. RT-qPCR results manifested the inhibitory effects of ucOCN on the expression of osteoclastic marker genes in RAW264.7 cells during inducing differentiation of RANKL. It was also observed that ucOCN inhibited the formation of multinucleated cells from RAW264.7 cells and BMMs detected by TRAP staining. The number and area of bone resorb pits were also decreased after treatment with ucOCN during their osteoclast induction by toluidine blue staining. The formation and integrity of the osteoclast actin ring were impaired by ucOCN by immunofluorescent staining. Time dependant treatment of ucOCN during osteoclastic induction demonstrated the inhibitory effects mainly occurred at the early stage of osteoclastogenesis. Signaling analysis of luciferase activity of the CRE or SRE reporter and ERK1/2 phosphorylation showed the selective inhibitor or siRNA of Gprc6a (a presumptive ucOCN receptor) could attenuate the promotion of ucOCN on CRE-luciferase activity. Taken together, we provided the first evidence that ucOCN had negative effects on the early differentiation and bone resorption of osteoclasts via Gprc6a.
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Microgravity impacts various aspects of human health. Yet the mechanisms of spaceflight-induced health problems are not elucidated. Here, we mapped the fusion systemic analysis of the serum metabolome and the circulating microRNAome in a hindlimb unloading rat model to simulate microgravity. The response of serum metabolites and microRNAs to simulated microgravity was striking. Integrated pathway analysis of altered serum metabolites and target genes of the significantly altered circulating miRNAs with Integrated Molecular Pathway-Level Analysis (IMPaLA) software was mainly suggestive of modulation of neurofunctional signaling pathways. Particularly, we revealed significantly increased miR-383-5p and decreased aquaporin 4 (AQP4) in the hippocampus. Using rabies virus glycoprotein-modified exosomes, delivery of miR-383-5p inhibited the expression of AQP4 not only in rat C6 glioma cells in vitro but also in the hippocampus in vivo. Using bioinformatics to map the crosstalk between the circulating metabolome and miRNAome could offer opportunities to understand complex biological systems under microgravity. Our present results suggested that the change of miR-383-5p level and its regulation of target gene AQP4 was one of the potential molecular mechanisms of microgravity-induced cognitive impairment in the hippocampus.
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The aim of present study was to develop folic acid (FA)-modified nonionic surfactant vesicles (NISVs, niosomes) as carrier systems for targeted delivery of gambogenic acid (GNA). The FA-GNA-NISVs exhibited a mean particle size of 180.77 ± 2.41 nm with a narrow poly dispersion index of 0.147 ± 0.08 determined by dynamic light scattering. Transmission electron microscopy also revealed that the FA-GNA-NISVs were spherical with double-layer structure. Entrapment efficiency (EE%) and zeta potential of the optimal FA-GNA-NISVs were 87.84 ± 1.06% and -37.33 ± 0.33 mV, respectively. Differential scanning calorimetry demonstrated that the GNA was in a molecular or amorphous state inside the FA-NISVs in vitro release profiles suggested that FA-GNA-NISVs could release GNA at a sustained manner, and less than 60% of GNA was released from the FA-NISVs within 12 hours of dialysis. in vivo pharmacokinetic results illustrated that FA-GNA-NISVs had considerably higher Cmax , area under curve (AUC0 - t ) and accumulation in lung. The cell proliferation study shown that the FA-GNA-NISVs significantly enhanced the in vitro cytotoxicity against A549 cells. Flow cytometry and fluorescence microscopy further demonstrated that the FA-GNA-NISVs increased apoptosis compared with nonmodified GNA-NISVs and free GNA. Moreover, FA-GNA-NISVs induced A549 cell apoptosis in a dose-dependent manner. In addition, cellular uptake assays showed a higher uptake of FA-GNA-NISVs than GNA-NISVs as well as free GNA. Taken together, it could be concluded that FA-GNA-NISVs were proposed as a novel targeting carriers for efficient delivering of GNA to cancers cells.
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Ácido Fólico/química , Tensoactivos/química , Xantenos/farmacología , Células A549 , Animales , Apoptosis/efectos de los fármacos , Liberación de Fármacos , Endocitosis/efectos de los fármacos , Humanos , Liposomas , Tamaño de la Partícula , Ratas Sprague-Dawley , Electricidad Estática , Distribución Tisular/efectos de los fármacos , Xantenos/administración & dosificación , Xantenos/química , Xantenos/farmacocinéticaRESUMEN
In this study, a novel mixed polymeric micelles formed from biocompatible polymers, poly(ethylene glycol)-poly(lactide) (mPEG-PLA) and poly(ethylene glycol)-poly(É-caprolactone) (mPEG-PCL), used as a novel nanocarrier to encapsulate gambogenic acid (GNA). GNA-loaded mixed polymeric micelles (GNA-MMs) was prepared by cosolvent evaporation method. The mean average size of GNA-MMs was (83.23 ± 1.06) nm (n = 3) and entrapment efficiency (EE%) of GNA-MMs was (90.18 ± 2.59) % (n = 3) as well as (12.36 ± 0.64) % (n = 3) for drug loading (DL%). Transmission electron microscopy revealed that the GNA-MMs were spherical with "core-shell" structures. Compared with free GNA solution, in vitro release of GNA from GNA-MMs showed a two-phase sustained release profile: an initial relatively fast phase and followed by a slower release phase. Pharmacokinetic results also indicated that the GNA-MMs have longer systemic circulation time and slower plasma elimination rate than free GNA solution. Moreover, the in vitro cytotoxicity assay showed that the IC50 values on HepG2 cells for GNA-MMs and free GNA were (5.67 ± 0.02) µM and (9.02 ± 0.03) µM, respectively. In addition, GNA-MMs significantly increased the HepG2 cellular apoptosis in a concentration-dependent manner. In conclusion, the results showed that mPEG-PLA/mPEG-PCL mixed micelles may serve as an ideal drug delivery system for GNA to prolong drug circulation time in body, enhance bioavailability and retained its potent antitumor effect.
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Sistemas de Liberación de Medicamentos/métodos , Micelas , Poliésteres/química , Polietilenglicoles/química , Xantenos/química , Células Hep G2 , HumanosRESUMEN
West Nile virus (WNV) causes West Nile fever and West Nile encephalitis. Because infection by WNV creates serious public health problems, its simple, rapid, and visual detection is very important in clinical practice, especially in resource-limited laboratories. We have developed a rapid, specific, and highly sensitive internally controlled reverse transcription recombinase-aided amplification (RTRAA) assay to detect WNV, using both real-time fluorescence and the lateral flow dipstick (LFD) at 39.0 °C for 30 min. The analytical sensitivity of the RT-RAA assay was 10 plasmid copies and 1.6 pfu per reaction with real-time fluorescence, and 1,000 plasmid copies per reaction with the LFD. No crossreaction with other control viruses was observed. Compared with the RT-qPCR assay, the RT-RAA assay demonstrated 100% sensitivity and 100% specificity for WNV.
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Microgravity influences the activity of osteoblast, induces actin microfilament disruption and leads to bone loss during spaceflight. Mechanical stress such as gravity, regulates cell function, response and differentiation through dynamic cytoskeleton changes, but the mechanotransduction mechanism remains to be fully elucidated. Previous, we demonstrated actin microfilament mediated osteoblast Cbfa1 responsiveness to BMP2 under simulated microgravity (SMG). Here, we explored a potential molecular and its detailed mechanism of actin cytoskeleton functioning on BMP2-Smad signaling in MC3T3-E1 under SMG. Results showed that the actin microfilament-disrupting agent, cytochalasin B (CB), reduced BMP2-induced activation, translocation of Smad1/5/8 and Runx2 expression. SMG also inhibited BMP2-Smad signaling, which was rescued by actin cytoskeleton stabilizing agent, Jasplakinolide (JAS). Furthermore, we found that siRNA mediated knockdown of calponin 1 (CNN1), an actin binding protein, markedly promoted BMP2-Smad signaling and abolished both inhibition of CB, SMG on BMP2-Smad signaling and the rescue action of JAS. Overexpression of CNN1 inhibited the p-Smad induced by BMP2. Bidirectional Co-IP experiments demonstrated CNN1 could interacted with Smad or p-Smad protein. Furthermore, CB or SMG decreased the phosphorylated CNN1 and increased its interaction with Smad or p-Smad. Combined with the phosphorylation of CNN1 inhibites its actin binding activity, these results indicate that actin cytoskeleton depolymerization inhibites BMP2 signaling via blocking of Smad by dephosphorylated CNN1 in osteoblast cells. Thus, we provide new important insights into the mechanism of mechanotransduction under SMG condition, which probably contribute to bone formation decrease induced by SMG.
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Citoesqueleto de Actina/metabolismo , Proteína Morfogenética Ósea 2/fisiología , Proteínas de Unión al Calcio/metabolismo , Mecanotransducción Celular , Proteínas de Microfilamentos/metabolismo , Osteoblastos/metabolismo , Proteínas Smad/metabolismo , Animales , Línea Celular , Masculino , Ratones , Osteoblastos/fisiología , Fosforilación , Ratas , Ratas Sprague-Dawley , Simulación de Ingravidez , CalponinasRESUMEN
Objective Objective To analyze the torque performance of lingual brackets with slots in different directions and the influence pattern of arch wires with different sizes and materials on torque of these lingual brackets.Methods The finite element models of the anterior maxilla lingual brackets with vertical and horizontal slot were constructed,using 3 kinds of materials (stainless steel,beta-titanium,nickel-titanium) and two sizes of arch wires (0.43 mm x 0.56 mm,0.41 mm x 0.56 mm),so as to compare and analyze their mechanical properties after the application of torque load on the left upper central incisors with a rotation angle of ±20°.Results With the increase in elastic modulus of the arch wire,torque moments of lingual brackets with horizontal and vertical slot both increased gradually.Torque performance of lingual brackets was affected more by the sizes and materials of arch wires than the directions of slots.The lingual bracket with vertical slot produced 1-2 times of torque force than that with horizontal slot under the same degree of torque angle.The effect of arch wire sizes was smaller than that of arch wire materials,while the synergistic change in sizes and materials of arch wires had the largest influence on torque performance of lingual brackets.Conclusions The torque performance of lingual bracket will be influenced with its different slot directions,the sizes and materials of arch wires.In clinical application,slot directions of lingual brackets as well as sizes and materials of arch wires should be adjusted properly according to the required torque force.
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Objective To analyze the torque performance of lingual brackets with slots in different directions and the influence pattern of arch wires with different sizes and materials on torque of these lingual brackets. Methods The finite element models of the anterior maxilla lingual brackets with vertical and horizontal slot were constructed, including three kinds of materials (stainless steel, beta-titanium, nickel-titanium) and two sizes of arch wires (0.43 mm×0.56 mm, 0.41 mm×0.56 mm), so as to compare and analyze their mechanical properties after the application of torque load on the left upper central incisors with a rotation angle of ±20°. Results With the increase in elastic modulus of the arch wire, torque moments of lingual brackets with horizontal and vertical slot both increased gradually. Torque performance of lingual brackets was affected more by the sizes and materials of arch wires than the directions of slots. The lingual bracket with vertical slot produced 1-2 times of torque force than that with horizontal slot under the same degree of torque angle. The effect of arch wire sizes was smaller than that of arch wire materials, while the synergistic change in sizes and materials of arch wires had the largest influence on torque performance of lingual brackets. Conclusion The lingual brackets with different slot directions, sizes and materials of arch wires will influence the torque performance of lingual brackets. In clinical application, slot directions of lingual brackets as well as sizes and materials of arch wires should be adjusted properly according to the required torque force.
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Objective Objective To analyze the torque performance of lingual brackets with slots in different directions and the influence pattern of arch wires with different sizes and materials on torque of these lingual brackets.Methods The finite element models of the anterior maxilla lingual brackets with vertical and horizontal slot were constructed,using 3 kinds of materials (stainless steel,beta-titanium,nickel-titanium) and two sizes of arch wires (0.43 mm x 0.56 mm,0.41 mm x 0.56 mm),so as to compare and analyze their mechanical properties after the application of torque load on the left upper central incisors with a rotation angle of ±20°.Results With the increase in elastic modulus of the arch wire,torque moments of lingual brackets with horizontal and vertical slot both increased gradually.Torque performance of lingual brackets was affected more by the sizes and materials of arch wires than the directions of slots.The lingual bracket with vertical slot produced 1-2 times of torque force than that with horizontal slot under the same degree of torque angle.The effect of arch wire sizes was smaller than that of arch wire materials,while the synergistic change in sizes and materials of arch wires had the largest influence on torque performance of lingual brackets.Conclusions The torque performance of lingual bracket will be influenced with its different slot directions,the sizes and materials of arch wires.In clinical application,slot directions of lingual brackets as well as sizes and materials of arch wires should be adjusted properly according to the required torque force.
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Objective Objective To analyze the torque performance of lingual brackets with slots in different directions and the influence pattern of arch wires with different sizes and materials on torque of these lingual brackets.Methods The finite element models of the anterior maxilla lingual brackets with vertical and horizontal slot were constructed,using 3 kinds of materials (stainless steel,beta-titanium,nickel-titanium) and two sizes of arch wires (0.43 mm x 0.56 mm,0.41 mm x 0.56 mm),so as to compare and analyze their mechanical properties after the application of torque load on the left upper central incisors with a rotation angle of ±20°.Results With the increase in elastic modulus of the arch wire,torque moments of lingual brackets with horizontal and vertical slot both increased gradually.Torque performance of lingual brackets was affected more by the sizes and materials of arch wires than the directions of slots.The lingual bracket with vertical slot produced 1-2 times of torque force than that with horizontal slot under the same degree of torque angle.The effect of arch wire sizes was smaller than that of arch wire materials,while the synergistic change in sizes and materials of arch wires had the largest influence on torque performance of lingual brackets.Conclusions The torque performance of lingual bracket will be influenced with its different slot directions,the sizes and materials of arch wires.In clinical application,slot directions of lingual brackets as well as sizes and materials of arch wires should be adjusted properly according to the required torque force.