1.Genetic Determinants of Immune Cells and Hepatocellular Carcinoma Risk: A Bioinformatics and Bidirectional Mendelian Randomization Study
Tong WU ; Fei GAO ; Fei TENG ; Qiaoli ZHANG
Cancer Research on Prevention and Treatment 2025;52(1):42-51
Objective To identify core targets of hepatocellular carcinoma (HCC) by using bioinformatics and specific algorithms, explore their relationships with immune cells, and investigate the causal relationships between immune cells and HCC through Mendelian randomization. Methods Relevant genes associated with the development of HCC were screened using the GEO and TCGA databases. Immune infiltration analysis was conducted using GSVA and CIBERSORT algorithms. A bidirectional Mendelian randomization analysis was then performed to explore the causal relationships between immune cells and HCC. Results A total of 284 HCC-related genes were identified, with 120 genes recognized within the protein interaction network. Immune infiltration analysis revealed significant correlations between key genes and immune cells. Mendelian randomization results indicated that HLA DR on CD33+ HLA DR+ CD14dim (OR=1.097, 95%CI: 1.002–1.201, P=0.045, PBonferroni=0.091) and CD8 on CD28+ CD45RA+ CD8+ T cell (OR=1.123, 95%CI: 1.027–1.228, P=0.011, PBonferroni=0.022) were the risk factors for HCC. Conversely, HLA DR++ monocyte absolute count was identified as a protective factor for HCC (OR=0.812, 95%CI: 0.702–0.938, P=0.005, PBonferroni=0.139). Conclusion The occurrence and development of liver cancer may be related to CDK1, CCNB1, and CDC20, showing a high degree of correlation with Th2 cells, T helper cells, Th17 cells, and DCs. Mendelian randomization shows that HLA DR on CD33+HLA DR+ CD14dim and CD8 on CD28+CD45RA+CD8+T cells are associated with an increased risk of HCC. The risk of hepatocellular carcinoma is associated with a decrease in the level of HLA DR++monocyte absolute count.
2.Efficacy of stereotactic body radiotherapy combined with sintilimab and bevacizumab in treatment of unresectable hepatocellular carcinoma
Teng ZHANG ; Quan WANG ; Wengang LI ; Xuezhang DUAN
Journal of Clinical Hepatology 2025;41(1):69-74
ObjectiveTo investigate the efficacy and safety of stereotactic body radiotherapy (SBRT) combined with sintilimab and bevacizumab in the treatment of patients with unresectable hepatocellular carcinoma (uHCC) and related prognostic factors. MethodsA total of 42 patients with uHCC who underwent SBRT combined with sintilimab and bevacizumab in Department of Radiation Oncology, The Fifth Medical Centre of PLA General Hospital, from March to December 2022 were enrolled. The prescribed dose of planning target volume was 36 — 50 Gy in 5 — 6 fractions for continuous irradiation, followed by the regimen of sintilimab and bevacizumab. Each course of treatment was 3 weeks until the presence of tumor progression or serious adverse events. The Kaplan-Meier method was used to calculate overall survival (OS) rate and progression-free survival (PFS) rate, and the log-rank test was used for comparison between groups; the Cox proportional hazards model was used to investigate the influencing factors for prognosis. ResultsThe median follow-up time was 21.6 months, with an objective response rate of 69%, a disease control rate of 85.7%, a median PFS of 10.0 months (95% confidence interval [CI]: 6.7 — 13.0), and a median OS of 23.3 months (95%CI: 14.7 — 31.8). Most adverse events were grade 1 — 2 events, and there were no fatal adverse events. At 6 — 8 weeks after treatment, the AFP response group had a significantly better OS than the non-AFP response group (not reached vs 11.8 months, P=0.007). The multivariate analysis showed that AFP response was associated with the good prognosis of patients (hazard ratio=0.31, 95%CI: 0.13 — 0.75, P=0.009). ConclusionFor patients with uHCC, SBRT combined with sintilimab and bevacizumab can improve survival with a manageable safety profile, and a >50% reduction in AFP at 6 — 8 weeks after treatment can be used as a potential prognostic indicator.
3.Dispersion effect of bone cement after vertebroplasty using individualized unilateral external pedicle approach and bilateral pedicle approach
Lichuang ZHANG ; Wen YANG ; Guangjiang DING ; Peikun LI ; Zhongyu XIAO ; Ying CHEN ; Xue FANG ; Teng ZHANG
Chinese Journal of Tissue Engineering Research 2025;29(4):800-808
BACKGROUND:According to existing clinical studies,vertebroplasty treatment with both the external pedicle approach and the pedicle approach can improve the pain and quality of life of patients with spinal compression fractures.Compared with the pedicle approach,the external pedicle approach has a freer puncture angle,and good bone cement dispersion effect can be obtained by adjusting the puncture angle. OBJECTIVE:To compare the impact of vertebroplasty through individualized unilateral external pedicle approach and bilateral pedicle approach on the treatment of spinal compression fractures by quantifying the dispersion effect of bone cement. METHODS:A total of 80 patients with thoracolumbar compression fracture were divided into two groups by random number table method.The bilateral pedicle group(n=40)underwent vertebroplasty through a bilateral pedicle approach,while the unilateral external pedicle group(n=40)underwent individualized vertebroplasty through a unilateral external pedicle approach.Anteroposterior and lateral X-rays of the affected vertebrae from two groups of patients were photographed to assess effect and type of bone cement dispersion within 3 days after surgery.Visual analog scale score,tenderness threshold around fracture,and Oswestry dysfunction index were assessed before,1,7 days,and 1 month after surgery. RESULTS AND CONCLUSION:(1)Dispersion effect of bone cement in unilateral external pedicle group was better than that in bilateral pedicle group(P<0.001),and the amount of bone cement perfusion was higher than that in bilateral pedicle group(P<0.001).In the bilateral pedicle group,the bone cement dispersion types were mainly concentrated in type Ⅰ and type Ⅲ,while in the unilateral external pedicle group,the bone cement dispersion types were mainly concentrated in type I and type Ⅱ,and there was a significant difference in bone cement dispersion types between the two groups(P<0.001).(2)Postoperative visual analog scale scores and Oswestry disability index of both groups were lower than those before surgery(P<0.001),and postoperative tenderness threshold around fracture showed a trend of decreasing first and then increasing.At the same time point after treatment,there were no significant differences in visual analog scale score,Oswestry disability index,and tenderness threshold around fracture between the two groups(P>0.05).(3)The results indicate that individualized vertebroplasty via unilateral external pedicle approach can achieve better bone cement dispersion,and the treatment effect is consistent with the vertebroplasty via classical bilateral pedicle approach.
4.Increasing toe-out angle during drop-landing can diminish risk of inversion injuries among individuals with chronic ankle instability
Xiaoxue ZHU ; Qiongqiu ZHAO ; Teng ZHANG ; Dan WANG ; Jihong QIU ; Qipeng SONG ; Peixin SHEN
Chinese Journal of Tissue Engineering Research 2025;29(9):1827-1833
BACKGROUND:Individuals with chronic ankle instability are prone to inversion ankle sprains during landing.Moderately increasing the foot toe-out angle during landing may reduce the occurrence of inversion ankle sprains,but no studies have directly demonstrated this effect. OBJECTIVE:To explore the effect of increased toe-out angle during landing on the peak inversion angle,peak angular velocity,and the time to peak inversion among individuals with and without chronic ankle instability. METHODS:A total of 60 participants were recruited for this study,including 30 individuals with chronic ankle instability and 30 without chronic ankle instability.The study utilized a simulated sprain apparatus for drop-landing tests,featuring a platform that could tilt forward by 24° and inward by 15°,thus simulating the foot position during an ankle inversion sprain.Participants were required to perform drop-landing tests under two landing conditions:natural landing and toe-out landing,with the latter involving a greater foot toe-out angle,over 150%more than the former.Kinematic data of participants were recorded using a 12-camera three-dimensional motion capture system.Data analysis was conducted using two-way repeated measures analysis of variance and Spearman correlation analysis. RESULTS AND CONCLUSION:(1)Significant main effects of condition were found for peak inversion angle during drop-landing(P<0.001,η2 p=0.270),peak inversion velocity(P=0.015,η2 p=0.098),and peak inversion time(P<0.001,η2 p=0.260);a significant main effect of group was found for peak inversion velocity(P=0.029,η2 p=0.080).(2)There were significant negative correlations between the foot toe-out angle at landing and the peak ankle inversion angle(P=0.021,r=-0.310;P=0.042,r=-0.278)as well as the peak inversion time(P=0.018,r=-0.312;P=0.021,r=-0.309)in both chronic ankle instability and non-chronic ankle instability groups.Moreover,a significant negative correlation was also found between the foot toe-out angle and peak inversion velocity in the chronic ankle instability group(P=0.021,r=-0.312).(3)It is indicated that increasing the foot toe-out angle at landing can reduce the peak inversion angle,peak inversion velocity,and the peak inversion time during landing in patients with chronic ankle instability and non-chronic ankle instability,thereby decreasing the risk of ankle inversion sprains.
5.Mechanism of IGF2BP2 regulation of PPAR-γ/GLUT4 pathway in insulin resistance induced by sodium arsenite exposure in HepG2 cells
Shiqing XU ; Zhida HU ; Qiyao ZHANG ; Siqi ZHAO ; Yujie WANG ; Xiaohui WANG ; Teng MA ; Li WANG
Journal of Environmental and Occupational Medicine 2025;42(4):400-407
Background Arsenic is an environmentally harmful substance that causes hepatic insulin resistance and liver damage, increasing the risk of type 2 diabetes mellitus. Objective To explore whether the insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) is involved in insulin resistance in HepG2 cells after arsenic exposure through the peroxisome-proliferator-activated receptor γ (PPAR-γ) / glucose transporter 4 (GLUT4) pathway. Methods Cell viability was determined using cell counting kit 8 (CCK8) and an appropriate NaAsO2 infection dose was determined. A cellular arsenic exposure model of HepG2 cells was established by four concentrations of NaAsO2 solution for 24 h (the experiment was divided into four groups: 0, 2, 4, and 8 μmol·L−1); HepG2 cells were firstly treated with pcDNA3.1-IGF2BP2 and pcDNA3.1-NC respectively for 6 h, then with 8 μmol·L−1 NaAsO2 for 24 h to establish a IGF2BP2 overexpression cell model (the experiment was divided into 4 groups: control, NaAsO2, NaAsO2+pcDNA3.1-IGF2BP2, and NaAsO2+pcDNA3.1-NC); finally the cells were subject to 100 nmol·L−1 insulin stimulation for 30 min. Glycogen and glucose in HepG2 cells were determined by glycogen and glucose assay kits; mRNA expression levels of IGF2BP2 were measured by quantitative real-time PCR; protein expression levels of IGF2BP2, PPAR-γ, and GLUT4 in HepG2 were detected by Western blot (WB); and the binding of IGF2BP2 to PPAR-γ and PPAR-γ to GLUT4 was verified by co-immunoprecipitation (CO-IP) experiment. Results The results of CCK8 experiment showed a dose-effect relationship between NaAsO2 concentration and cell viability. When the concentration of NaAsO2 was ≥4 μmol·L−1 , the cell viabilities were lower than that of the control group (P <0.05). With the increasing dose of NaAsO2 infection, reduced glucose consumption and glycogen levels in HepG2 cells were found in the 2, 4, and 8 μmol·L−1 NaAsO2 treatment groups compared to the control group (P <0.05). The difference between the mRNA expression level of IGF2BP2 in the HepG2 cells treated with 4 or 8 μmol L−1 NaAsO2 and the control group was significant (P <0.05). In the IGF2BP2 overexpression cell model, compared with the control group, glucose consumption and glycogen levels were lowered in the NaAsO2 group (P <0.05), the mRNA expression level of IGF2BP2 and the protein expression levels of IGF2BP2, PPAR-γ, and GLUT4 in the cell membrane were all decreased (P <0.05). Compared with the NaAsO2 group, the glucose consumption and glycogen levels were increased in the NaAsO2+pcDNA3.1-IGF2BP2 group (P <0.05), and the mRNA expression level of IGF2BP2 and the protein expression levels of IGF2BP2, PPAR-γ, and GLUT4 in the cell membrane were all increased (P <0.05). The results of CO-IP experiments showed that IGF2BP2 interacted with PPAR-γ as well as PPAR-γ with GLUT4 protein. Conclusion IGF2BP2 is involved in arsenic exposure-induced insulin resistance in HepG2 cells by acting on the PPAR-γ/GLUT4 pathway.
6.Carvedilol to prevent hepatic decompensation of cirrhosis in patients with clinically significant portal hypertension stratified by new non-invasive model (CHESS2306)
Chuan LIU ; Hong YOU ; Qing-Lei ZENG ; Yu Jun WONG ; Bingqiong WANG ; Ivica GRGUREVIC ; Chenghai LIU ; Hyung Joon YIM ; Wei GOU ; Bingtian DONG ; Shenghong JU ; Yanan GUO ; Qian YU ; Masashi HIROOKA ; Hirayuki ENOMOTO ; Amr Shaaban HANAFY ; Zhujun CAO ; Xiemin DONG ; Jing LV ; Tae Hyung KIM ; Yohei KOIZUMI ; Yoichi HIASA ; Takashi NISHIMURA ; Hiroko IIJIMA ; Chuanjun XU ; Erhei DAI ; Xiaoling LAN ; Changxiang LAI ; Shirong LIU ; Fang WANG ; Ying GUO ; Jiaojian LV ; Liting ZHANG ; Yuqing WANG ; Qing XIE ; Chuxiao SHAO ; Zhensheng LIU ; Federico RAVAIOLI ; Antonio COLECCHIA ; Jie LI ; Gao-Jun TENG ; Xiaolong QI
Clinical and Molecular Hepatology 2025;31(1):105-118
Background:
s/Aims: Non-invasive models stratifying clinically significant portal hypertension (CSPH) are limited. Herein, we developed a new non-invasive model for predicting CSPH in patients with compensated cirrhosis and investigated whether carvedilol can prevent hepatic decompensation in patients with high-risk CSPH stratified using the new model.
Methods:
Non-invasive risk factors of CSPH were identified via systematic review and meta-analysis of studies involving patients with hepatic venous pressure gradient (HVPG). A new non-invasive model was validated for various performance aspects in three cohorts, i.e., a multicenter HVPG cohort, a follow-up cohort, and a carvediloltreating cohort.
Results:
In the meta-analysis with six studies (n=819), liver stiffness measurement and platelet count were identified as independent risk factors for CSPH and were used to develop the new “CSPH risk” model. In the HVPG cohort (n=151), the new model accurately predicted CSPH with cutoff values of 0 and –0.68 for ruling in and out CSPH, respectively. In the follow-up cohort (n=1,102), the cumulative incidences of decompensation events significantly differed using the cutoff values of <–0.68 (low-risk), –0.68 to 0 (medium-risk), and >0 (high-risk). In the carvediloltreated cohort, patients with high-risk CSPH treated with carvedilol (n=81) had lower rates of decompensation events than non-selective beta-blockers untreated patients with high-risk CSPH (n=613 before propensity score matching [PSM], n=162 after PSM).
Conclusions
Treatment with carvedilol significantly reduces the risk of hepatic decompensation in patients with high-risk CSPH stratified by the new model.
7.Development and Initial Validation of the Multi-Dimensional Attention Rating Scale in Highly Educated Adults.
Xin-Yang ZHANG ; Karen SPRUYT ; Jia-Yue SI ; Lin-Lin ZHANG ; Ting-Ting WU ; Yan-Nan LIU ; Di-Ga GAN ; Yu-Xin HU ; Si-Yu LIU ; Teng GAO ; Yi ZHONG ; Yao GE ; Zhe LI ; Zi-Yan LIN ; Yan-Ping BAO ; Xue-Qin WANG ; Yu-Feng WANG ; Lin LU
Chinese Medical Sciences Journal 2025;40(2):100-110
OBJECTIVES:
To report the development, validation, and findings of the Multi-dimensional Attention Rating Scale (MARS), a self-report tool crafted to evaluate six-dimension attention levels.
METHODS:
The MARS was developed based on Classical Test Theory (CTT). Totally 202 highly educated healthy adult participants were recruited for reliability and validity tests. Reliability was measured using Cronbach's alpha and test-retest reliability. Structural validity was explored using principal component analysis. Criterion validity was analyzed by correlating MARS scores with the Toronto Hospital Alertness Test (THAT), the Attentional Control Scale (ACS), and the Attention Network Test (ANT).
RESULTS:
The MARS comprises 12 items spanning six distinct dimensions of attention: focused attention, sustained attention, shifting attention, selective attention, divided attention, and response inhibition.As assessed by six experts, the content validation index (CVI) was 0.95, the Cronbach's alpha for the MARS was 0.78, and the test-retest reliability was 0.81. Four factors were identified (cumulative variance contribution rate 68.79%). The total score of MARS was correlated positively with THAT (r = 0.60, P < 0.01) and ACS (r = 0.78, P < 0.01) and negatively with ANT's reaction time for alerting (r = -0.31, P = 0.049).
CONCLUSIONS
The MARS can reliably and validly assess six-dimension attention levels in real-world settings and is expected to be a new tool for assessing multi-dimensional attention impairments in different mental disorders.
Humans
;
Adult
;
Male
;
Attention/physiology*
;
Female
;
Middle Aged
;
Reproducibility of Results
;
Young Adult
;
Psychometrics
8.The Predictive Value of Serum sIL-2R Combined with TNF-α, IgG and IgA in the Recurrence of Multiple Myeloma.
Ping LIN ; Ya-Lan ZHANG ; Ruo-Teng XIE ; Xue-Ya ZHANG
Journal of Experimental Hematology 2025;33(1):150-156
OBJECTIVE:
To investigate the predictive value of serum soluble interleukin-2 receptor(sIL-2R), tumor necrosis factor alpha(TNF-α), IgG and IgA for the recurrence in patients with multiple myeloma(MM).
METHODS:
A total of 108 MM patients who were initially diagnosed and treated in our hospital from January 2017 to March 2019, and 72 patients who met the diagnostic criteria and had complete follow-up data were selected as the study subjects. MM recurrence was the endpoint event, and follow-up was conducted until the occurrence of the endpoint event or the deadline of this study. MM patients were divided into recurrent group(RG) and non-recurrent group(NRG) based on whether they have relapsed or not. Venous blood was collected from patients at the first diagnosis and follow-up (at the occurrence of endpoint events or termination of the study), and enzyme-linked immunosorbent assay(ELISA) was used to detect sIL-2R and TNF-α levels in the patient's serum. An automatic immune analyzer was used to detect the levels of IgG and IgA in the patient's serum. The differences in expression levels of the factors between two groups were compared and the correlations between sIL-2R and TNF-α, IgG and IgA at the first diagnosis and follow-up were analyzed. At the same time, venous blood was collected from patients during complete remission, and their serum sIL- 2R levels were measured to compare the differences in sIL-2R expression levels at the first diagnosis, complete remission and recurrence. Receiver operating characteristic(ROC) curves was used to determine the optimal cutoff values for serum sIL-2R, TNF-α, IgG and IgA, and the predictive value of sIL-2R, TNF-α, IgG and IgA in the recurrence of MM patients were analyzed based on the area under the curve(AUC).
RESULTS:
The serum sIL-2R levels of MM patients at the first diagnosis and recurrence were significantly higher than at complete remission (P < 0.05). At the first diagnosis, the hemoglobin content of RG was lower than that of NRG, while the β2-microglobulin content was higher than that of NRG (P < 0.001). There was no significant difference in other clinical parameters between the two groups (P >0.05). The levels of sIL-2R, TNF-α, IgG and IgA at the first diagnosis and follow-up of RG were higher than those of NRG (P < 0.05). There was a significant correlation between sIL-2R and TNF-α, IgG and IgA at the first diagnosis and follow-up (P < 0.001). The ROC curve showed that, at the first diagnosis, sIL-2R, TNF-α, IgG and IgA predicted the AUC of MM patients were 0.919, 0.850, 0.766 and 0.795, respectively, after follow-up, they predicted AUC of MM were 0.890, 0.815, 0.760 and 0.794, respectively (P < 0.001).
CONCLUSION
The serum sIL-2R has the highest predictive value for MM patient's recurrence, and it is possible to detect the TNF-α, IgG and IgA levels at specific times to infer changes in sIL-2R levels and evaluate the patient's prognosis.
Humans
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Multiple Myeloma/blood*
;
Immunoglobulin A/blood*
;
Immunoglobulin G/blood*
;
Tumor Necrosis Factor-alpha/blood*
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Receptors, Interleukin-2/blood*
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Recurrence
;
Male
;
Female
;
Neoplasm Recurrence, Local
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Middle Aged
;
Prognosis
9.Retrospective Analysis of Venetoclax Combined with Azacitidine Compared with "3+7" or Similar Regimens for Newly Diagnosed Patients with Acute Myeloid Leukemia.
Lu-Lu WANG ; Juan ZHANG ; Yue ZHANG ; Yong ZHANG ; Xiao-Min DONG ; Dan-Yang ZHANG ; Ting-Ting CHEN ; Yun-Hui ZHOU ; Teng WANG ; Hui-Ling LAN ; He-Bing ZHOU
Journal of Experimental Hematology 2025;33(3):672-681
OBJECTIVE:
To retrospectively analyze the clinical data of newly diagnosed acute myeloid leukemia (AML) patients treated with venetoclax combined with azacitidine (Ven/Aza) or standard "3+7" regimen and similar regimens, collect real-world study data, compare the treatment response and adverse events between the two regimens, as well as perform survival analysis.
METHODS:
To retrospectively analyze the efficacy, survival, and adverse reactions of newly diagnosed AML patients treated with Ven/Aza (24 cases) and "3+7" regimens (117 cases ) in our hospital from September 2009 to March 2023, as well as factors influencing outcomes. A propensity score matching (PSM) was performed on age and Eastern Cooperative Oncology Group performance status (ECOG PS) to obtain a 1:1 matched cohort of 20 pairs, and the efficacy and survival before and after the matching were compared.
RESULTS:
The median age of patients in the Ven/Aza group was 69 years, while that in the "3+7" group was 56 years (P <0.001). Objective remission rate (ORR) was 62.5% in Ven/Aza group and 74.8% in "3+7" group (P >0.05). The median overall survival (OS) in the Ven/Aza group was 522 days, while that in the "3+7" group was 1 002 days (P >0.05). After controlling the two variables of age and ECOG PS, a PSM cohort of 20 pairs was obtained, in which the ORR was 65% in Ven/Aza group and 60% in "3+7" group (P >0.05). The median OS was 522 days and 629 days, and median progression-free survival (PFS) was 531 days and 198 days between the two groups, respectively. There were no statistically significant differences in OS and PFS between the two groups (both P >0.05). Additionally, the incidence of adverse events in the Ven/Aza group was significantly reduced.
CONCLUSION
The overall cohort shows that the "3+7" regimen has advantages in efficacy and survival, but Ven/Aza regimen is relatively safer. After performing PSM on age and ECOG PS, the Ven/Aza group showed improved efficacy, and a longer median PFS compared to "3+7" group.
Humans
;
Leukemia, Myeloid, Acute/drug therapy*
;
Retrospective Studies
;
Sulfonamides/administration & dosage*
;
Azacitidine/administration & dosage*
;
Bridged Bicyclo Compounds, Heterocyclic/administration & dosage*
;
Aged
;
Middle Aged
;
Male
;
Female
;
Antineoplastic Combined Chemotherapy Protocols/therapeutic use*
;
Treatment Outcome
10.Three-dimensional finite element analysis of digital wire loop space maintainers for missing deciduous teeth.
Lijuan MA ; Yonghui TENG ; Yong WANG ; Yijiao ZHAO ; Xinyue ZHANG ; Qingzhao QIN ; Dong YIN
Journal of Peking University(Health Sciences) 2025;57(2):376-383
OBJECTIVE:
To establish a three-dimensional finite element model of a digital wire loop space maintainer for the mandible and primary tooth loss, in order to investigate the stress, deformation, and shear force experienced by patients with the loss of the second primary molar when wearing the wire loop space maintainer.
METHODS:
Cone beam computed tomography (CBCT) scans were performed on the patients to create a digital model of the mandible with the absence of the second primary molar using Mimics 21.0 software. A digital model integrating the crown's retention and the wire loop structure of the full crown and ring wire loop space maintainer was constructed using pediatric space maintainer design software, utilizing three different materials: cobalt-chromium alloy, polyether ether ketone (PEEK), and titanium alloy. In ANSYS Work Beach 2023 R2 software, vertical loads of 70 N, tilted 45° along the long axis of the tooth loads of 70 N, and a 10 N load on the surface of the wire loop were applied to the occlusal surfaces of models 46 and 84, simulating centric and lateral occlusions during chewing with the wire loop space maintainer in place. The stress states of the wire loop space maintainer and supporting teeth were analyzed.
RESULTS:
Under various loading conditions, the maximum principal stress of the ring wire loop space maintainer was significantly lower than that of the full crown. Stress contour maps indicated that the peak of the maximum principal stress occurred at the junction of the wire loop and crown structure, indicating that this area was more susceptible to fracture. The ring wire loop space maintainer made from PEEK material exhibited the lowest maximum shear stress on the internal organizational surfaces, with equivalent stresses of 23.18 MPa and 36.35 MPa for models 46 and 84, respectively. Stress contour maps demonstrated that the maximum stress on tooth 46 was located at its mesial, while the maximum stress on tooth 84 was situated near the root area on its distal, in contact with the wire loop space maintainer.
CONCLUSION
In cases of second primary molar loss, wearing the digital ring wire loop space maintainer can effectively distribute stress, and the ring wire loop space maintainer made from PEEK material reduces the stress experienced by supporting teeth to some extent, demonstrating its superiority in clinical application.
Finite Element Analysis
;
Humans
;
Tooth, Deciduous
;
Cone-Beam Computed Tomography
;
Space Maintenance, Orthodontic/methods*
;
Imaging, Three-Dimensional
;
Orthodontic Wires
;
Dental Stress Analysis
;
Mandible
;
Stress, Mechanical

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