1.Finite element analysis of various root shield thicknesses in maxillary central incisor socket-shield technique
Guangneng CHEN ; Siyang LUO ; Mei WANG ; Bin YE ; Jiawen CHEN ; Yin LIU ; Yuwen ZUO ; Xianyu HE ; Jiajin SHEN ; Minxian MA
Chinese Journal of Tissue Engineering Research 2025;29(10):2052-2060
BACKGROUND:Socket-shield technique can effectively maintain labial soft and hard tissues,but the incidence of postoperative complications such as exposure and displacement of root shield is relatively high.It is speculated that the root shield may be exposed and displaced due to excessive load after long-term function of dental implants. OBJECTIVE:Through three-dimensional finite element analysis,we aim to study the influence of varying root shield thicknesses on the stress distribution,equivalent stress peaks,and displacement in the root shield,periodontal ligaments,implant,and surrounding alveolar bone under normal occlusal loading.We also attempt to analyze the correlation between the thickness of the root shield and occurrence of mechanical events such as root shield exposure,displacement,and fracture. METHODS:Cone-beam CT data of a patient who met the indication standard of socket-shield technique for maxillary central incisor were retrieved from database.Reverse engineering techniques were used to build models of the maxillary bone and root shield,while forward engineering was used to create models for the implant components based on their parameters.Models depicting various root shield thicknesses(0.5,1.0,1.5,and 2.0 mm)were created using Solidworks 2022 software.ANSYS Workbench 2021 software was then used to simulate and analyze the effects of varying root shield thicknesses on stress distribution,equivalent stress peaks,and displacement of the root shields,periodontal ligaments,implants,and surrounding alveolar bone under normal occlusion. RESULTS AND CONCLUSION:(1)In all root shield models,the stress was concentrated on the palatal cervical side,both sides of the edges and the lower edge of the labial side.As the thickness of the root shield increased,the equivalent stress peak and displacement showed a decreasing trend.The 0.5 mm thickness model produced a stress concentration of 176.20 MPa,which exceeded the yield strength(150 MPa)of tooth tissue.(2)The periodontal ligament stress in each group was concentrated in the neck margin and upper region.With the increase of root shield thickness,the equivalent stress peak and displacement of periodontal ligament showed a decreasing trend.(3)Implant stress in all models was concentrated in the neck of the implant and the joint of the implant-repair abutment,and the labial side was more concentrated than the palatal side.With the increase of root shield thickness,the equivalent stress peak of the implant in the model showed an increasing trend.(4)In each group of models,stress of cortical bone concentrated around the neck of the implant and the periphery of the root shield,and the labial side was more concentrated than the palatal side.With the increase of the thickness of the root shield,the equivalent stress peak around the root shield decreased;the peak value of the equivalent stress of the bone around the neck of the implant showed an increasing trend.In the model,the stress of cancellous bone was mainly concentrated around the neck of the lip of the implant,the top of the thread,the root tip and the lower margin of the root shield,and the labial side was more concentrated than the palatal side.With the increase of the thickness of the root shield,the peak value of the equivalent stress of the bone around the root shield in the model showed a decreasing trend.The minimum principal stress of cortical bone in each group of models was concentrated around the neck of the implant,exhibiting a fan-shaped distribution.As the thickness of the root shield increased,the minimum principal stress of cortical bone showed an increasing trend.(5)These results indicate that different thicknesses of the root shield have different biomechanical effects.The root shield with a thickness of 0.5 mm is easy to fracture.For patients with sufficient bone width,the root shield with a thickness of 2.0 mm is an option to reduce the risk of complications such as root shield exposure,fracture,and displacement.Meanwhile,it should be taken into account to protect the periodontal ligament in the preparation process,and rounding treatments ought to be carried out on both sides and the lower edge of the root shield.
2.Artificial intelligence model for diagnosis of coronary artery disease based on facial photos
Li LIN ; Tingfeng XU ; Yaodong DING ; Yang ZHANG ; Jichao WANG ; Yaxin ZUO ; Gong ZHANG ; Minxian WANG ; Yong ZENG
Chinese Journal of Cardiology 2024;52(11):1272-1276
Objective:To develop and validate an artificial intelligence (AI) diagnostic model for coronary artery disease based on facial photos.Methods:This study was a cross-sectional study. Patients who were scheduled to undergo coronary angiography (CAG) at Beijing Anzhen Hospital and Beijing Daxing Hospital from August 2022 to November 2023 were included consecutively. Before CAG, facial photos were collected (including four angles: frontal view, left and right 60° profile, and top of the head). Photo datasets were randomly divided into a training set, a validation set (70%), and a testing set (30%). The model was constructed using Masked Autoencoder (MAE) and Vision Transformer (ViT) architectures. Firstly, the model base was pre-training using 2 million facial photos obtained from the publicly available VGGFace dataset, and fine-tuned by the training and validation sets; the model was validated in the test set. In addition, the ResNet architecture was used to process the dataset, and its outputs were compared with those of the models based on MAE and ViT. In the test set, the area under the operating characteristic curve ( AUC) of the AI model was calculated using CAG results as the gold standard. Results:A total of 5 974 participants aged 61 (54, 67) years were included, including 4 179 males (70.0%), with a total of 84 964 facial photos. There were 79 140 facial photos in the training and validation sets, with 3 822 patients with coronary artery disease; there were 5 824 facial photos in the test set, with 239 patients with coronary artery disease. The AUC value of the MAE and ViT model initialized with pre-training model weights was 0.841 and 0.824, respectively. The AUC of the ResNet model initialized with random weights was 0.810, while the AUC of the ResNet model initialized with pre-training model weights was 0.816. Conclusion:The AI model based on facial photos showes good diagnostic performance for coronary artery disease and holds promise for further application in early diagnosis.
3.Distribution and health risk of residual trihalomethane in regional drinking water
Xuefei PANG ; Minxian ZHAO ; Qiang LIU ; Xiaolong ZHOU ; Songwen LU ; Ying WANG ; Wei LIANG ; Haibing YANG
Shanghai Journal of Preventive Medicine 2023;35(12):1212-1217
ObjectiveTo explore the variation rules and health risks of trihalomethane in regional drinking water, and to provide evidence for the innovative water processing technology and the optimization of drinking water quality. MethodsBased on regional drinking water sanitation monitoring, non-parametric rank sum test was used to analyze the effects of residual trihalomethane production in different periods and with disinfection methods. The United States environmental protection agency (USEPA) classic "four-step" health risk assessment model was used to evaluate the carcinogenic risk and non-carcinogenic risk of trihalomethane through drinking water exposure. ResultsThe yield of trichloromethane in wet season was 6.3 μg·L-1, which was higher than that in dry season. Compared with chlorination pretreatment, ozone pretreatment reduced the content of bromomethane dichloromethane. Compared to liquid chlorine disinfection, sodium hypochlorite treatment incresed the levels of trichloromethane and bromomethane chloride. Although the total carcinogenic and non-carcinogenic risks of trihalomethane in drinking water in the region were at safe levels, they were above the acceptable limits occasionally. The highest carcinogenic risk of trihalomethane were dichlorobromomethane and chlorodibromomethane,and the highest non-carcinogenic risk was trichloromethane. The health risk of children was 1.2 times higher than that for adults. ConclusionThe production of residual trihalomethane in drinking water in this area is relatively low, which is less harmful to the health of adults and children. Monitoring, including other disinfection byproducts, should continue and appropriate disinfection techniques for drinking water should be explored.
4.Development and application of a chemical transformational method for the indirect measurement of ligustilide content in Angelica sinensis
Peng-cheng WU ; Pan ZHAO ; Xing-ping LUO ; Yun-jie WANG ; Xiao-ning WEI ; Quan HAO ; Peng-wei LIU ; Rui-li LIN ; Lin NI ; Ping-shun SONG ; Jun-xi LIU
Acta Pharmaceutica Sinica 2021;56(3):841-848
The poor stability of the ligustilide (LIG) makes its quantitation in
5.A cross-sectional study on psychological needs of family members of critically ill inpatients in semi-closed wards and analysis of influence factors
Qinqi XU ; Wenliang WANG ; Yin ZHANG ; Minxian WANG ; Zhengchuan DONG
Chinese Journal of Burns 2021;37(5):475-484
Objective:To analyze and discuss the psychological needs of family members of critically ill burn inpatients in semi-closed wards and their related influence factors.Methods:A cross-sectional survey was conducted among the 82 burn patients, who met the inclusion criteria and were admitted to the Department of Burns and Plastic Surgery of Ruijin Hospital of Shanghai Jiao Tong University School of Medicine from October 2018 to April 2019, and their family members. A general condition questionnaire of 15 indexes was applied to investigate the general data of burn patients and their family members including cause of burn, gender, age, total burn area, burn depth, burn severity, burn site, and type of medical insurance of patients, kinship with the patients, gender, age, experience of accompanying in intensive care isolation wards, occupation, education level, and monthly income of their family members. The Critical Care Family Needs Inventory (CCFNI) was used to assess each item, each factor, and total scores of the family members of patients including 5 factors and 45 items such as support scale (SS), comfort scale (CS), information scale (IS), proximity scale (PS), assurance scale (AS). CCFNI was used to assess the total scores of patients and their family members after classification according to the general data, the data were statistically analyzed with one-way analysis of variance or independent sample t test. Indicators with statistical significance in the above analysis were selected for multiple linear regression analysis to screen the independent influence factors of psychological needs of patients' family members. CCFNI was used to assess each dimension scores of patients and their family members after classification according to the aforementioned selected independent influence factors including age and burn area of patients, gender, educational level, and experience of accompanying in intensive care isolation wards of their family members, and the data were statistically analyzed with one-way analysis of variance or independent sample t test. Results:A total of 82 questionnaires were sent out in this study, and 80 were effectively received, with s a recovery rate of 97.6%. In 80 patients, there were 45 males and 35 females; 35 cases (43.75%) were ≤14 years; most of the patients had flame and thermal burns; 33 patients (41.25%), 21 patients (26.25%), and 26 patients (32.50%) had moderate, severe, and extremely severe burns, respectively; and only 3 patients (3.75%) had no health insurance. In 80 family members of patients, 34 (42.50%) were males and 46 (57.50%) were females; 62.50% in the family members of patients were concentrated between 18 and 45 years old; and 12 family members of patients had experience of accompanying in intensive care isolation wards, accounting for 15.00%. The total CCFNI score of the family members was (141±14) points, and the scores of AS, PS, IS, CS, and SS were (3.77±0.23), (3.43±0.37), (3.53±0.34), (2.50±0.59), and (2.69±0.45) points, respectively. The top five items of the psychological needs of family members of patients were concentrated in three factors (AS, PS, and IS), and the item "ensuring that patients receive the best treatment" ranked the first, with a score of (3.99±0.11) points. There were significant differences on the CCFNI total scores of patients with different age, total burns area, and severity of burns and of their family members with different gender, education level, and whether or not experience of accompanying in intensive care isolation unit ( F=4.378, 5.481, 5.913, t=4.027, 14.339, 7.265, P<0.05 or P<0.01). Multiple linear regression analysis showed that the patient's age (≤14, 15-45 years) and total burn area (11%-30%, 31%-49%, ≥50% TBSA) and the patient's family members' gender, educational level, experience of accompanying in intensive care isolation unit could affect the psychological needs of family members of patients ( t=3.133, 2.260, 2.297, 2.433, 3.015, 2.200, 2.102, 2.463, P<0.05 or P<0.01). There was statistically significant difference in AS score of the patients' family members with different age ( F=4.390, P<0.05). There were significant differences in both IS and AS scores of the patients' family members of patients with different burn area ( F=5.042, 3.131, P<0.05 or P<0.01). The AS score of the patients' family members with experience of accompanying in intensive care isolation unit was significantly lower than those without ( t=-1.040, P<0.05). The SS score of the patients' family members with college education or above was significantly higher than those with high school (technical secondary school) or below ( t=0.657, P<0.05). The IS score of the patients' family members with college education or above was significantly lower than those with high school (technical secondary school) or below ( t=-1.438, P<0.05). The SS score of male family members of patients was significantly lower than those of female patients ( t=4.149, P<0.05). Conclusions:The family members of burn patients in semi-closed ward have the most urgent need to ensure the patients receive the best treatment. Patients' age, total burn area, and their family members' gender, education level, experience of accompanying in intensive care isolation unit are the main factors affecting the psychological needs of family members of patients.
6.Extracorporeal shock wave treatment for palm crush injuries
Zhanyu YANG ; Haiyan YAN ; Yang LI ; Anying FENG ; Lijun WU ; Minxian WANG ; Yu ZHU
Chinese Journal of Physical Medicine and Rehabilitation 2020;42(10):915-918
Objective:To observe the clinical effect of extracorporeal shock wave treatment in the treatment of functional disorders after a palm crush injury.Methods:Forty patients who had experienced a hand crush injury more than 3 months previously were randomly divided into a control group and a combination group, each of 20. Both groups were given routine joint mobilization, ultrasound treatment, muscle strength training and occupational therapy every day in ten day units for 2 months. The combination group also received extracorporeal shock wave therapy three times a week for the two months. Before the experiment and after one and two months of treatment, both groups′ upper limb functioning was evaluted using the DASH score, grip strength and hand flexibility in the 9-hole wood board test.Results:After 2 months of treatment, significant improvement was observed in all of the measurements with both groups. The average scores of the combination group on all three tests were by then significantly better than the control group′s averages.Conclusions:Adding extracorporeal shock wave therapy to routine rehabilitation can improve the rough and fine functioning of a crushed hand.
7.Concept analysis of pressure injury-related pain
Liuxin ZHANG ; Ru ZHANG ; Yuling ZHONG ; Minxian WANG ; Min WANG ; Xianwen LI ; Jie WANG
Chinese Journal of Modern Nursing 2020;26(31):4428-4431
With the in-depth research on pressure injury, pressure injury-related pain has gradually attracted attention, but its definition is not uniform yet, and there is a lack of targeted assessment tools. This research systematically searches the Chinese and English literature related to pressure injury-related pain published from 1995 to 2019, and uses Rodgers' evolutionary concept analysis method to systematically analyze the concept, and clarify its defining attributes, causes and consequences. This research also puts forward the attributes of pressure injury-related pain, clarifies related concepts such as chronic wound-related pain and wound-related pain, as well as the concept with typical cases, so as to provide a reference for the management of pressure-related pain.
8.Three-dimensional reconstruction based on DICOM data and its application for orthopedic implants
Jing LI ; Long YANG ; Jianji WANG ; Qin LIU ; Qiang ZOU ; Yu SUN ; Minxian MA ; Chuan YE
Chinese Journal of Tissue Engineering Research 2017;21(7):1046-1051
BACKGROUND:The output of computed tomography (CT) is Digital Imaging and Communications in Medicine (DICOM), whereas the input of three-dimensional (3D) printing is an object Standard Template Library model represented by a triangular mesh. The process of data handing and forrmat conversion are keys to the combination of these two techniques. OBJECTIVE:To explore how to convert CT data into a stereoscopic 3D model efficiently. METHODS:The DICOM in Medicine format data of the patients with femoral fractures were edited and produced by Mimics. We made a 3D model by adjusting the parameters of the 3D printer slicing software, and discussed the significance of 3D model in medical field, especially orthopedics. RESULTS AND CONCLUSION:Mimics software is the bridge to connect two-dimensional CT scan images and 3D images, to create a 3D model by editing the data of DICOM which comes from the CT scanner, with a 3D printing technology. The 3D Model can help doctors for routine clinical diagnosis and treatment, to improve the communication between doctors and patients and the quality of clinical medical teaching. 3D printing also makes medicine more personalized, remote, minimally invasive, and promote the development of medicine to the direction of digital medicine.
9.Development and application of special-purpose grafter by femoral head decompression combined with bone marrow mesenchymal stem cells transplantation based on three-dimensional printing technology
Jianji WANG ; Long YANG ; Jing LI ; Qi SUN ; Weimin ZUO ; Qifeng REN ; Yu SUN ; Zhanyu WU ; Qiang ZOU ; Minxian MA ; Chuan YE
Chinese Journal of Tissue Engineering Research 2016;20(44):6636-6642
BACKGROUND:Autologous tissue-engineered bone marrow mesenchymal stem cel s (BMSCs) transplantation is one of the most common methods of treating early osteonecrosis of femoral head, but now there is stil no any special-purpose grafter available in the market. Such surgical transplantation is a laborious, time-consuming and tedious process, which goes against its clinical promotion. OBJECTIVE:To develop a supporting, efficient, special-purpose grafter, to solve the difficulty in stem cel s transplantation during core decompression of femoral head. METHODS:CAD software was used to perform solid modeling for this special-purpose grafter and print them by three-dimensional (3D) fast printing technology. The performance of this special-purpose grafter was tested by femoral head core decompression combined with BMSCs transplantation. It was compared with traditional surgical instrument in terms of duration of operation, intraoperative blood loss, visual analogue scale (VAS) of stem cel/biological fiber col agen complex omission amount and doctor’s satisfaction score. RESULTS AND CONCLUSION:(1) A kind of special-purpose grafter was developed by 3D printing technology rapidly. (2) Compared with the control group, duration of operation, intraoperative blood loss, VAS scores and doctor’s satisfaction scores were significantly improved in the trial group (P<0.05). (3) CAD software combined with 3D printing technology is a highly efficient means for front-line clinicians to perform independent development. The research and development of this special-purpose grafter provides a perfect solution to the laborious, time-consuming and tedious process of cel/biological col agen fiber transplantation.
10.Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) scaffolds carrying human bone marrow mesenchymal stem cells for bone tissue engineering
Junbiao ZHANG ; Zhixu HE ; Chuan YE ; Yong WANG ; Mei WANG ; Qin LIU ; Long YANG ; Jing LI ; Minxian MA
Chinese Journal of Tissue Engineering Research 2016;20(21):3057-3064
BACKGROUND:As a noticeable tissue engineering material of polyhy droxyalka noates family, poly (3-hydroxybutyrate-co-4-hydroxybutyrate)(P3HB4HB) exhibitsgood biocompatibility, adhesion and mechanicalproperties, presenting aextensive application future in tissue-engineered research.
OBJECTIVE:To investigate the biocompat ibilityin vitroand ectopic osteogenic differentiationin vivoof P3HB4HB and human bone marrow mesenchymal stem cels.
METHODS:Passage 5human bone marrow mesenchymal stem cels transplanted ontothe three-dimensional P3HB4HB scaffoldwereincubated with osteogenic induction medium (test group)or with no osteogenic induction(control group), respectively. After 5-day incubation, thecelgrowth was assessed by acridine orange staining and scanning electron microscopy; after14-day incubation, both kinds of cel-scaffold composites were subcutaneously implanted into the nude mice. At 16 weeks after implantation, the cel-scaffold composites were removed to observeectopic osteogenic differentiationin vivousing hematoxylin-eosin staining, von Kossa staining and colagen type I immunohistochemical staining.
RESULTS AND CONCLUSION:Acridine orange staining showed that cels adhered wel on the surface of the scaffold;under thescanning electron microscope, induced celsgrew wel on the P3HB4HB scaffold and produced abundant extracelular matrixes. In addition, at 16 weeks after implantation, there were osteoidtissues in the test group, positive for von Kossa staining as wel as colagen type I immunohistochemical staining;furthermore, hematoxylin-eosin staining showednumerous osteoblasts and bone lacunas. In contrast, no bone tissues appeared in the control group. To conclude, P3HB4HB is a suitable material for bone tissue engineering.

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