1.Three-dimensional finite element analysis of molar distalization with clear aligners with different thicknesses and edges
Yanan CHENG ; Jiazhi YU ; Yinchang LIU ; Jie WU ; Tong YU ; Lu WANG ; Xiaoguang LI
Chinese Journal of Tissue Engineering Research 2026;30(2):310-318
BACKGROUND:One of the advantages of clear aligner treatment is molar distalization.However,tooth tilting movement and loss of anterior anchorage may occur during treatment.There are few studies on whether these problems can be improved by selecting clear aligners with different thicknesses and edges to improve the clinical treatment effect.OBJECTIVE:To analyze the control ability of clear aligners with different thickness and edges on the central incisor,lateral incisor,and second molar when pushing the maxillary second molar distally by three-dimensional finite element analysis.METHODS:Three-dimensional finite element analysis models of bilateral maxillary second molar distalization with clear aligner,maxillary dentition,periodontal ligament,and alveolar bone with different thicknesses and margins were established by Mimics,Geomagic Wrap,3-matic and SolidWorks software,respectively.There were 16 combinations of four thicknesses(0.4,0.5,0.625,and 0.75 mm)and four margins(scallop,straight,straight extension 2 mm and straight extension 4 mm).The data were imported into Ansys Workbench software for design and solution.The mean value,peak value and distribution of the periodontal ligament equivalent stress of the second molar,the equivalent stress and the maximum initial displacement of the second molar,and the control ability of each appliance on the second molar,central incisor,and lateral incisor were analyzed.RESULTS AND CONCLUSION:(1)The mean equivalent stress of periodontal ligament of the second molar,the equivalent stress of the second molar and the maximum initial displacement of the second molar increased with the extension of the appliance edge and the increase of the thickness of the appliance in the 16 groups of models.(2)When the thickness of appliances was the same,the maximum equivalent stress of the second molar in the linear appliance group was the highest,and the maximum equivalent stress of the second molar in the linear extended appliance group was greater than that in the scallop appliance group.When the edge of the appliance was the same,the periodontal ligament equivalent stress peak of the second molar increased with the increase of the thickness of the appliance.The equivalent stress distribution in the periodontal ligament of the second molar in the linear extendable appliance group was more uniform than that in the scallop appliance group and the linear appliance group.(3)When the thickness of the appliance was the same,the scallop-shaped appliance had the worst control on the second molar.When the edge of the appliance was the same,with the increase of the thickness of the appliance,the control of the second molar by the linear extender appliance was gradually stronger than that by the linear appliance.The control of the central incisor was stronger and more stable with the linear extended 2 mm appliance,while the control of the lateral incisor was stronger and more stable with the linear appliance.(4)The results showed that when using clear aligners to push molars distally,extending the edge of the appliance could improve the control of the molars and reduce the tilting movement of the teeth.The design of a straight extension margin of 2 mm for the central incisor and a straight edge for the lateral incisor can enhance the control of the anchorage incisor and reduce the labial inclination of the anterior teeth.
2.Three-dimensional finite element analysis of molar distalization with clear aligners with different thicknesses and edges
Yanan CHENG ; Jiazhi YU ; Yinchang LIU ; Jie WU ; Tong YU ; Lu WANG ; Xiaoguang LI
Chinese Journal of Tissue Engineering Research 2026;30(2):310-318
BACKGROUND:One of the advantages of clear aligner treatment is molar distalization.However,tooth tilting movement and loss of anterior anchorage may occur during treatment.There are few studies on whether these problems can be improved by selecting clear aligners with different thicknesses and edges to improve the clinical treatment effect.OBJECTIVE:To analyze the control ability of clear aligners with different thickness and edges on the central incisor,lateral incisor,and second molar when pushing the maxillary second molar distally by three-dimensional finite element analysis.METHODS:Three-dimensional finite element analysis models of bilateral maxillary second molar distalization with clear aligner,maxillary dentition,periodontal ligament,and alveolar bone with different thicknesses and margins were established by Mimics,Geomagic Wrap,3-matic and SolidWorks software,respectively.There were 16 combinations of four thicknesses(0.4,0.5,0.625,and 0.75 mm)and four margins(scallop,straight,straight extension 2 mm and straight extension 4 mm).The data were imported into Ansys Workbench software for design and solution.The mean value,peak value and distribution of the periodontal ligament equivalent stress of the second molar,the equivalent stress and the maximum initial displacement of the second molar,and the control ability of each appliance on the second molar,central incisor,and lateral incisor were analyzed.RESULTS AND CONCLUSION:(1)The mean equivalent stress of periodontal ligament of the second molar,the equivalent stress of the second molar and the maximum initial displacement of the second molar increased with the extension of the appliance edge and the increase of the thickness of the appliance in the 16 groups of models.(2)When the thickness of appliances was the same,the maximum equivalent stress of the second molar in the linear appliance group was the highest,and the maximum equivalent stress of the second molar in the linear extended appliance group was greater than that in the scallop appliance group.When the edge of the appliance was the same,the periodontal ligament equivalent stress peak of the second molar increased with the increase of the thickness of the appliance.The equivalent stress distribution in the periodontal ligament of the second molar in the linear extendable appliance group was more uniform than that in the scallop appliance group and the linear appliance group.(3)When the thickness of the appliance was the same,the scallop-shaped appliance had the worst control on the second molar.When the edge of the appliance was the same,with the increase of the thickness of the appliance,the control of the second molar by the linear extender appliance was gradually stronger than that by the linear appliance.The control of the central incisor was stronger and more stable with the linear extended 2 mm appliance,while the control of the lateral incisor was stronger and more stable with the linear appliance.(4)The results showed that when using clear aligners to push molars distally,extending the edge of the appliance could improve the control of the molars and reduce the tilting movement of the teeth.The design of a straight extension margin of 2 mm for the central incisor and a straight edge for the lateral incisor can enhance the control of the anchorage incisor and reduce the labial inclination of the anterior teeth.
3.Application of transnasal endoscopic approach for clipping the paraclival internal carotid artery in skull base surgery
Haiyan LI ; Pingping HU ; Minggang SHI ; Xu WANG ; Yanguo SHANG ; Xiaoguang TONG ; Gang LIU ; Guodong FENG ; Xiang ZHAI
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2025;60(10):1291-1297
Objective:To evaluate the feasibility and outcomes of transnasal endoscopic clipping of the paraclival internal carotid artery (ICA) in skull base surgery.Methods:The paraclival ICA was anatomically dissected in cadaveric head specimens. The clinical data of 15 patients with skull base lesions involving the ICA who admitted to the Department of Otorhinolaryngology Head and Neck Surgery at Tianjin Huanhu Hospital from January 2021 to December 2023 were retrospectively analyzed. Among them, 4 patients underwent transnasal endoscopic clipping of the paraclival ICA and concurrent lesion resection. The surgical methods were summarized, and the key points and indications of this technique were analyzed.Results:Intraoperative clipping of the ICA was successful and hemostatic in all 4 patients. Postoperatively, 3 patients had no complications, while 1 patient developed delayed ischemic cerebral infarction. Two patients were cured, 1 patient was maintained on immunotherapy, and 1 patient died. During follow-up, the clip was in situ in 1 patient, had detached in another, and was obscured by temporal muscle coverage in the remaining 2 patients.Conclusions:Transnasal endoscopic clipping of the paraclival ICA represents a potential option for managing the ICA in skull base surgery. However, it carries significant risks and limitations, mandating careful patient selection based on specific circumstances.
4.Application of transnasal endoscopic approach for clipping the paraclival internal carotid artery in skull base surgery
Haiyan LI ; Pingping HU ; Minggang SHI ; Xu WANG ; Yanguo SHANG ; Xiaoguang TONG ; Gang LIU ; Guodong FENG ; Xiang ZHAI
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2025;60(10):1291-1297
Objective:To evaluate the feasibility and outcomes of transnasal endoscopic clipping of the paraclival internal carotid artery (ICA) in skull base surgery.Methods:The paraclival ICA was anatomically dissected in cadaveric head specimens. The clinical data of 15 patients with skull base lesions involving the ICA who admitted to the Department of Otorhinolaryngology Head and Neck Surgery at Tianjin Huanhu Hospital from January 2021 to December 2023 were retrospectively analyzed. Among them, 4 patients underwent transnasal endoscopic clipping of the paraclival ICA and concurrent lesion resection. The surgical methods were summarized, and the key points and indications of this technique were analyzed.Results:Intraoperative clipping of the ICA was successful and hemostatic in all 4 patients. Postoperatively, 3 patients had no complications, while 1 patient developed delayed ischemic cerebral infarction. Two patients were cured, 1 patient was maintained on immunotherapy, and 1 patient died. During follow-up, the clip was in situ in 1 patient, had detached in another, and was obscured by temporal muscle coverage in the remaining 2 patients.Conclusions:Transnasal endoscopic clipping of the paraclival ICA represents a potential option for managing the ICA in skull base surgery. However, it carries significant risks and limitations, mandating careful patient selection based on specific circumstances.
5.Indirect surgical technique for the treatment of giant internal carotid artery aneurysms:a single-center retrospective cohort study
Chinese Journal of Nervous and Mental Diseases 2024;50(7):415-422
Objective To summarize the single-center experience with indirect surgery(cerebrovascular bypass)for the treatment of giant internal carotid aneurysms(GICAs).Methods A retrospective analysis was conducted on the clinical outcomes of patients with GICAs treated using indirect surgical techniques at our center from May 2016 to May 2023.For patients who tested negative in the balloon occlusion test(BOT),internal carotid artery(ICA)constriction was performed with or without low-flow bypass from the superficial temporal artery(STA)to the middle cerebral artery(MCA).For patients who tested positive in the BOT,ICA ligation was combined with high-flow bypass(external carotid artery-radial artery-M2).Preoperative and postoperative O'Kelly-Marotta(OKM)grading and changes in the maximum diameter of the aneurysm were examined through cerebral angiography.The preoperative and postoperative modified Rankin Scale(mRS)scores and changes in clinical symptoms were followed up to evaluate the safety and efficacy of the indirect surgery.Results A total of 22 patients were included in this study.Sixteen patients underwent ICA constriction with or without STA-MCA bypass,while six patients underwent ICA ligation combined with high-flow bypass.Postoperative OKM grades reached C/D in 50% (11/22)of the patients,showing a statistically significant improvement compared to preoperative grades(P<0.0001).Postoperative or final imaging follow-up showed that the size of aneurysms was decreased in 19 patients,remained unchanged in 2 patients,and increased in 1 patient,which reached a statistically significant difference compared to preoperative measurements(t=5.439,P<0.001).Follow-up results indicated that the mRS scores of the 22 patients decreased significantly compared to preoperative scores(t=2.531,P=0.019).Conclusion In the era of neurointervention,indirect surgical techniques remain an important complementary approach for the treatment of refractory or recurrent GICAs.
6.Application of oliceridine combined with dexmedetomidine for prophylactic analgesia in patients undergoing endoscopic dacryocystorhinostomy
Kun ZHANG ; Xiaoyan TONG ; Xianming LEI ; Xing CHEN ; Qingbo XU ; Shaozhu HU ; Xiaoguang HE
China Pharmacist 2024;27(8):1383-1391
Objective To analyze the anesthetic effect and hemodynamic impact of oxybutynin(OBI)combined with dexmedetomidine(DEX)on patients undergoing endoscopic dacryocystorhinostomy(En-DCR).Methods Patients who underwent En-DCR from February 2024 to May 2024 at Mianyang Wanjiang Eye Hospital were recruited.They were randomly divided into the DEX group(DEX administration only)and the combined group(DEX combined with OLI administration)according to the random number table method.The primary observational index in this study was the 24-h postoperative pain numerical rating scale(NRS)scores.The secondary observation indexes were heart rate(HR),mean arterial pressure(MAP),respiratory recovery time(SRT),extubation time(ET)and awakening time(AT),peak systolic value(PSV),end-diastolic blood flow velocity(EDV),resistance index(RI)and blood flow(BF).The occurrence of adverse events in patients during hospitalization was observed and recorded.Results A total of 80 patients were included in the study,with 40 in each of the DEX group and the combined group.In terms of analgesia,the NRS scores in the combined group were lower than those in the DEX group at T1(within 0.5 h after catheter removal),T2(4 h postoperatively),T3(8 h postoperatively),and T4(24 h postoperatively)(P<0.05),and the remedial analgesia rate in the combined group was significantly lower than that in the DEX group(P<0.05).Regarding anesthetic effects,HR and MAP at time points T6(during induction of anesthesia),T7(intraoperatively)and T8(during resuscitation)were lower in the combined group than in the DEX group(P<0.05);and SRT,ET and AT were shorter in the combined group compared with the DEX group(P<0.05).In terms of hemodynamics,at 24 h postoperatively,PSV,EDV and BF were significantly higher in both groups compared with those before anesthesia,whereas RI was significantly lower than before anesthesia(P<0.05);PSV,EDV and BF were higher in the combined group than those in the DEX group,and RI was lower than that in the DEX group(P<0.05).Regarding adverse reactions,the incidence of adverse reactions in the combined group was significantly lower than that in the DEX group(P<0.05).Conclusion OLI combined with DEX prophylactic analgesia for patients with En-DCR is effective,not only to reduce postoperative pain,stabilize hemodynamics,shorten the time of extubation and awakening,and reduce the incidence of adverse reactions.
7.Analysis of factors influencing the expression levels of lung cancer circulating tumor markers in cerebrospinal fluid
Sun ZENGFENG ; Li PENG ; She CHUNHUA ; Tong XIAOGUANG
Chinese Journal of Clinical Oncology 2024;51(6):293-297
Objective:To analyze the normal expression levels of different lung cancer tumor markers(TM)in the cerebrospinal fluid and to explore the influence of serum TM levels and brain parenchymal metastasis,to more accurately determine whether the cerebrospinal fluid TM levels of patients with suspected meningeal metastasis is elevated.Methods:The clinical data of 80 patients diagnosed with non-lepto-meningeal metastasis at Tianjin Medical University Cancer Hospital between January 2015 and February 2024 were collected,including 16 patients without lung cancer and 64 patients with lung cancer.Normal TM levels in the cerebrospinal fluid of patients without lung cancer and the difference in TM levels between the cerebrospinal fluid and serum samples were analyzed.The correlation between serum and cerebrospinal fluid TM levels was also analyzed.We then compared the differences in TM levels in the cerebrospinal fluid between groups with brain parenchymal metastasis and without brain parenchymal metastasis.Results:Normal levels of TPSA,CA19-9,CEA,Cyfra21-1,and SCC in the cerebrospinal fluid were lower than those in the serum(P<0.05);however,the levels of ProGRP and NSE in the cerebrospinal fluid were higher than those in the serum(P<0.05).The levels of TPSA,SCC,ProGRP,NSE,CEA,CA19-9,and Cyfra21-1 in the cerebrospinal fluid did not correlate with those in the serum(all P>0.05).The cerebrospinal fluid levels of TPSA,SCC,ProGRP,and CA19-9 were not significantly increased in patients with brain parenchymal metastasis compared to those in patients without brain parenchymal metastasis(P>0.05).Al-though CEA and Cyfra21-1 levels increased(P<0.05),their median values increased by less than 2 times and were all within the reference range;whereas,the level of NSE in the group with brain parenchymal metastasis was lower than that in the control group.Conclusions:The basal levels of ProGRP and NSE in normal cerebrospinal fluid were significantly higher than those in the serum;whereas,the expression levels of other TM in the cerebrospinal fluid were significantly lower than those in the serum.Whether the levels of TM in the serum were elevated and whether brain parenchymal metastasis was present,did not have a clinically significant impact on the TM levels in the cerebrospinal fluid.
8.A qualitative study on optimizing influenza vaccination services and strategies for people aged 60 and above in Shanghai
Xiaolan WANG ; Tian YANG ; Caoyi XUE ; Linlin WU ; Yi FEI ; Xiaoguang YANG ; Biao XU
Shanghai Journal of Preventive Medicine 2024;36(10):977-982
ObjectiveTo understand the process and influencing factors affecting the utilization of influenza vaccination services and vaccination decision-making among the elderly in Shanghai, to explore the delivery of influenza vaccination services and the difficulties faced by the health service system, and to provide guidance for optimizing immunization strategies. MethodsBased on the vaccine hesitancy determinants matrix, semi-structured personal interviews were conducted with stakeholders involved in influenza vaccination services in Shanghai from January to February 2024, using a purposive sampling method. Participants were included until thematic saturation was achieved. Interview data were audio-recorded, transcribed, coded, and organized using NVivo 20 software, and analyzed using the thematic framework method. ResultsA total of 25 interviewees were included, including 9 medical staff, 12 elderly people aged 60 and above, and 4 family members. The study found that Shanghai had a well-managed and standardized influenza vaccination service. However, the promotion of vaccine-related information at the grassroots level was passive and limited. Out-of-pocket payment of the vaccine and cultural beliefs of the elderly negatively impacted vaccination rates. Meanwhile, recommendations from family, friends, and medical staff facilitated vaccination, although the impact varied depending on the type of medical staff. Neighborhood committees in townships and streets played a crucial role in delivering vaccination information to the target population. Additionally, the internet, social media, and the COVID-19 vaccine had both positive and negative impacts on influenza vaccination. Strategic optimization of vaccination should prioritize price concessions, enhance publicity strategies, and improve awareness, professionalism, and willingness among medical and healthcare workers to recommend vaccination. ConclusionThe influenza vaccination service in Shanghai is well-managed and standardized. However, it is essential to consider the influence of family and other support systems on the elderly. It is also necessary to enhance the professionalism, service awareness, and willingness to recommend among the medical staff. Furthermore, systematic interventions and publicity efforts should be effectively integrated with social media and the functions of neighborhood committees.
9.Coffee intake and cancer: an umbrella review of meta-analyses
Huiyi CHEN ; Min GAO ; Xiaoguang LI
Shanghai Journal of Preventive Medicine 2023;35(12):1259-1270
ObjectiveWith the increase in coffee consumption, its impact on health has garnered significant attention. However, the relationship between coffee intake and cancer risk remains controversial in epidemiological studies. To summarize the most reliable evidence on coffee consumption and cancer risk, we conducted a comprehensive review of meta-analyses examining the association between coffee consumption and cancer risk in various populations. MethodsMeta-analyses of observational studies were conducted, utilizing searches of the PubMed and Web of Science databases to identify associations between coffee intake and cancer risk. ResultsA total of 24 observational studies comprising 76 non-overlapping associations were included in this umbrella review. Coffee intake was found to be associated with a reduced risk of breast cancer, brain cancer, colon cancer, colorectal cancer, endometrial cancer, liver cancer, melanoma, non-melanoma, oral cancer, and oral/pharyngeal cancer. Conversely, coffee intake was associated with a high risk of urothelial carcinoma and bladder cancer. ConclusionModerate consumption of coffee has a wide range of potential benefits in reducing the risk of cancer. Further well-designed randomized controlled trials, taking into account other factors that may have contributed to bias, are needed to investigate the association between coffee consumption and cancer in other anatomical sites.
10.Host protection against Omicron BA.2.2 sublineages by prior vaccination in spring 2022 COVID-19 outbreak in Shanghai.
Ziyu FU ; Dongguo LIANG ; Wei ZHANG ; Dongling SHI ; Yuhua MA ; Dong WEI ; Junxiang XI ; Sizhe YANG ; Xiaoguang XU ; Di TIAN ; Zhaoqing ZHU ; Mingquan GUO ; Lu JIANG ; Shuting YU ; Shuai WANG ; Fangyin JIANG ; Yun LING ; Shengyue WANG ; Saijuan CHEN ; Feng LIU ; Yun TAN ; Xiaohong FAN
Frontiers of Medicine 2023;17(3):562-575
The Omicron family of SARS-CoV-2 variants are currently driving the COVID-19 pandemic. Here we analyzed the clinical laboratory test results of 9911 Omicron BA.2.2 sublineages-infected symptomatic patients without earlier infection histories during a SARS-CoV-2 outbreak in Shanghai in spring 2022. Compared to an earlier patient cohort infected by SARS-CoV-2 prototype strains in 2020, BA.2.2 infection led to distinct fluctuations of pathophysiological markers in the peripheral blood. In particular, severe/critical cases of COVID-19 post BA.2.2 infection were associated with less pro-inflammatory macrophage activation and stronger interferon alpha response in the bronchoalveolar microenvironment. Importantly, the abnormal biomarkers were significantly subdued in individuals who had been immunized by 2 or 3 doses of SARS-CoV-2 prototype-inactivated vaccines, supporting the estimation of an overall 96.02% of protection rate against severe/critical disease in the 4854 cases in our BA.2.2 patient cohort with traceable vaccination records. Furthermore, even though age was a critical risk factor of the severity of COVID-19 post BA.2.2 infection, vaccination-elicited protection against severe/critical COVID-19 reached 90.15% in patients aged ≽ 60 years old. Together, our study delineates the pathophysiological features of Omicron BA.2.2 sublineages and demonstrates significant protection conferred by prior prototype-based inactivated vaccines.
Humans
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Aged
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Middle Aged
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COVID-19/prevention & control*
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SARS-CoV-2
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Pandemics/prevention & control*
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China/epidemiology*
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Disease Outbreaks/prevention & control*
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Vaccination

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