1.The application of rapid prototyping in oral and maxillofacial prosthesis(1)——The revertible design of artificial mandible substitutes
Yaxiong LIU ; Dichen LI ; Bingheng LU
Journal of Practical Stomatology 2000;0(05):-
Objective: To enable an artificial mandible substitute to be mostly suitable for mandibular reconstructon in individual patients. Methods: Use rapid prototypinlg and surface imitating as the primary technology for individualized design and manufacturing of the artificial mandible substitute. Results: An individualized artificial mandible substitute was designed and prepared. Conclusion: Rapid prototyping is feasible in individualized bone substitute preparation.
2.The application of rapid prototyping to the oral and maxillofacial prosthesis(2)——The individualized manufacturing of artificial mandible substitutes
Yaxiong LIU ; Dichen LI ; Sanhu HE
Journal of Practical Stomatology 2000;0(05):-
Objective: To enable an artificial mandible substitute to be with individualized shape in the individual patient. Methods: Rapid prototyping and surface imitating were used as the primary technology in the individualized design and manufacturing of the artificial mandible substitute. Results: The shape and size of the manufactured artificial mandibe were almost the same to those of the original natural one. Conclusion: Rapid prototyping may be used in individualized bone substitute preparation.
3.Total knee arthroplasty based on the assistance of three-dimensional-printing personalized surgical navigation template
Bing QIU ; Mingjiao ZHANG ; Bensen TANG ; Biyong DENG ; Dichen LI ; Fei LIU
Chinese Journal of Tissue Engineering Research 2015;(48):7731-7735
BACKGROUND:With significantly individual differences in the anatomy of the knee joint, traditional total knee replacement is difficult to accurately predict the position of locating limb alignment, size of the prosthesis and osteotomy amount of patients during operation. OBJECTIVE:To investigate the clinical effect of total knee replacement based on the assistance of medical image reconstruction, computer-aided design technology and 3D-printing personalized surgical navigation template. METHODS:Medical image data of patients were col ected using CT or magnetic resonance scanning equipment. The three-dimensional reconstruction of the bone was conducted by two-dimensional medical image processing technology. The navigation template was designed by computer-aided design technology. The personalized surgical navigation templates were produced by 3D printing technology, and the clinical total knee replacement was conducted. The postoperative results were evaluated using imageology. RESULTS AND CONCLUSION:Arigin 3D Pro (Arigin Medical Co., Ltd.) can accurately reconstruct a three-dimensional model of the lower limb bones. The three-dimensional design software Arigin Surgical Templating by their independent research and development can precisely pinpoint related lower limb axis, including limb alignment, rotation axis of the femur and osteotomy reference point. The personalized navigation template we researched and produced for knee surgery fitted tightly with femoral condyle and tibial plateau bone anatomy during operation, without significant movement. The deviation of patients’ limb alignment was less than 3° after total knee replacement.
4.Lymphadenitis in cat scratch disease(CSD):A clinicopathological study
Xia GE ; Qun XIE ; Zenong CHENG ; Min YAO ; Dechun LIU ; Dichen LI
Chinese Journal of Clinical and Experimental Pathology 2001;(2):120-22
Purpose To study the main points of the diagnosis and differential diagnosis of the lymphadenitis in CSD. Methods Expression of CD45, CD3 and CD68 were evaluated immunohistochemically (S-P method). Results Five cases of microabscess in early stage and 21 cases of microabscess-granuloma were found. The histologic features were the formation of microabscess and granuloma. The early microabscess in the lymphnodes were surounded by B lymphocytes (CD20+) and macrophages (CD68+). The typial microabscess granuloma were surrounded by epitheloid cells (CD68+) and CD3 positive T lymphocytes. Conclusion The main characteristic of the lymphadenitis of cat scratch disease is the formation of granuloma with microabscess. The immumohistochemical markers are useful to distinguish the proliferative cell types. This lesion may result from bacterial infection which induces the cell immune reaction.
5.Tissue-engineered soft tissue oriented manufacturing technologies and additive manufacturing
Qin LIAN ; Dichen LI ; Cheng CHEN ; Weijie ZHANG ; Yaxiong LIU ; Jiankang HE ; Zhongmin JIN
Chinese Journal of Tissue Engineering Research 2014;(8):1263-1269
BACKGROUND:In recent years, many manufacturing techniques have been recently developed for soft tissue engineering scaffolds. Especialy additive manufacturing with a unique material accumulated forming principle can be feasible and reliable to manufacture the highly precise scaffolds with gradient structures and multi-materials for large soft tissue defect repairing.
OBJECTIVE:To summarize scaffolds manufacturing technologies in the soft tissue engineering applications developed in recent years and to predict the direction of development.
METHODS: A retrieval was performed for the literature about the manufacturing methods of soft tissue scaffolds using key words of “additive manufacturing, microfabrication, vascular tissue engineering, muscle tissue engineering, cartilage tissue engineering, stereolithography, 3D printing, biodegradable hydrogel” in English and Chinese, which were published between January 2010 and September 2013 in PubMed Database and China National Knowledge Infrastructure (CNKI) Database.
RESULTS AND CONCLUSION:For large soft tissue defects repairing, structure design of the scaffolds has been shifted from a simple planar structure to a more complex three-dimensional structure, and integration of scaffold structure, materials and cels, and growth factors during the manufacturing procedure can be used to obtain the resolution of vascularization. Additive manufacturings become one of the most promising approaches for the ideal soft tissue scaffolds with gradient and complex structure and multi-materials. In particular, the hydrogel/cellcomposite scaffolds fabrication, a hot but promising approach to develop the soft tissue engineering wil be made progress by the accurate principles and processes of the hydrogel additive manufacturing combined with the introduction of living cels and growth factors.
6.The development of the system of blood flow block by using magnetic compression abdominal large vascular.
Xiaopeng YAN ; Yi LV ; Feng MA ; Jia MA ; Haohua WANG ; Shanpei WANG ; Dichen LI ; Yaxiong LIU ; Shenli JIA ; Zongqian SHI ; Ruixue LUO
Chinese Journal of Medical Instrumentation 2014;38(2):107-109
A new system of blood flow block for control of bleeding in abdominal operation is composed of an abdominal magnetic blocking unit, an abdominal external electromagnet unit and other non-magnetic operation instrument. The abdominal external electromagnetic unit is placed in advance in the operation bed. The abdominal magnetic blocking unit can be placed directly on the ventral of the large vessels when need to blocking the abdominal large vessels during the operation. According to the non-contact suction characteristics of magnetic materials, the two magnetic units will attract each other and compression the vessels. Using this system for vascular occlusion does not need clear exposure and without separating vessel. There is the advantage of rapid, accurate and reliable for the system.
Abdomen
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blood supply
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Blood Loss, Surgical
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prevention & control
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Electromagnetic Phenomena
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Equipment Design
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Surgical Equipment
7.Study of the lymph node micrometastasis in patients with supraglottic carcinoma.
Jiwen ZHAO ; Yaping XU ; Yan ZHOU ; Fang ZHOU ; Dichen LIU
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2008;22(18):837-839
OBJECTIVE:
To explore an available and sensitive method to detect cervical lymph node micrometastasis in patients with laryngeal squamous cell carcinoma.
METHOD:
The primary tumors and 182 neck lymph nodes from Twenty cases with supraglottic cancer dissection were examined with immunohistochemical (IHC) staining using cytokeratin 19 (CK19), and haematoxylin and eosin (HgE) staining. The frequency of lymph node metastasis and the clinical relevance, and the relationship between overall survival time and lymph node metastases by Log Rank test were analyzed.
RESULT:
The expression of CK19 was 23. 6% of lymph nodes and all of the primary tumors. In Hg-E staining, 16.5% of lymph nodes were positive. There was highly significant difference between them. There were 88.4% lymph nodes, 9.3% lymph nodes and 2.3% lymph node corresponding to the II, III and IV levels by IHC. Lymph node metastases were detected on the II (86.7%) and III levels (13.3%) with H&E. The highest rate of positive lymph nodes was on the II level of the neck. There was highly significant difference between overall survival time and lymph node metastasis in CK19 analysis.
CONCLUSION
The expression of CK19 may be served as an available method to evaluate occult micrometastases in laryngeal squamous cell carcinoma. High frequency of CK19 was associated with a decreased probability of survival time.
Aged
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Carcinoma, Squamous Cell
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diagnosis
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pathology
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Female
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Glottis
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pathology
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Humans
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Keratin-19
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analysis
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Laryngeal Neoplasms
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diagnosis
;
pathology
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Lymph Nodes
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pathology
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Lymphatic Metastasis
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Male
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Middle Aged
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Neoplasm Staging
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Prognosis
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Staining and Labeling
8.3D printed external fixator for treatment of tibial fractures
Feng QIAO ; Dichen LI ; Zhongmin JIN ; Yongchang GAO ; Jinlong HE ; Shicheng ZHENG ; Shuguang LIU
Chinese Journal of Orthopaedics 2019;39(1):23-29
Objective To investigate the feasibility and primary clinical outcomes of a kind of independent research and development customized 3D printed external fixator in the treatment of tibial fracture.Methods Data of 7 tibial fracture patients who were treated using computer-assisted reduction and 3D printing technique including a new kind of customized external fixator with automatical reduction function from December 2013 to November 2015 were retrospectively analyzed.There were 5 males and 2 females in this cohort.The age of the patients ranged from 25 to 49 years old,with an average age of 38.1 years old.The procedure was as follows.At first,two or three pins were placed separately into the distal and proximal tibia away from fracture site.Then,the CT scanning was performed on the fractured tibia.According to the CT scanning data,the external fixator was designed by computer software and manufactured by the 3D printing technique.The reduction of tibial fracture was achieved automatically after the 3D printed external fixator was connected to the inserted pins.Finally,the accuracy of reduction was assessed by postoperative X-ray image.During the different fracture healing course,the stress environment could be dynamically adjusted by screwing or unscrewing the nuts to fulfill rigid fixation,compression fixation or elastic fixation for the bone healing.Results All the 7 cases had obtained successful reduction by only one time operation with the 3D printed external fixators.The average lateral angulation was 1.42°± 1.13°,and the average anteroposterior angulation was 1.65°± 1.36°,while the average lateral displacement was 1.38± 1.44 mm,and the average anteroposterior displacement was 1.83± 1.30 mm,which were measured from postoperative X-ray image.The individual durations of the operation were 9 min,8 min,9 min,1.5 min,1.4 min,1.4 min and 2.4 min,respectively.All fractures had achieved bony union in 19-25 weeks after operation,with an average time of 21.4±1.6 weeks.All patients were followed up for 6 months when removal of the external fixator,and no refracture occurred.Conclusion The customized 3D printed external fixator has the function of automatical reduction.In addition,it can provide three kinds of fixation modes,which are rigid fixation,compression fixation and elastic fixation.It has the advantages of simple operation,accurate reduction,reasonable fixation,etc.
9.Biomechanical Study of PEEK Condyle Prosthesis Printed by Fused Deposition Modeling and Selective Laser Sintering
Fang GUO ; Shuo HUANG ; Ning LIU ; Yongfeng LI ; Min HU ; Changquan SHI ; Dichen LI ; Changkui LIU
Journal of Medical Biomechanics 2021;36(2):E264-E270
Objective To make finite element analysis and compressive performance test on three-dimensional (3D) printed personalized poly-ether-ether-ketone (PEEK) condyle prosthesis, so as to analyze stress distribution characteristics and mechanical properties of the prosthesis, and to evaluate its clinical value and prospect. Methods The finite element models of PEEK condyle prosthesis, mandible and fixation screw were established by software such as CBCT, Mimics, Geomagic Studio, SolidWorks and ANSYS Workbench. The maximum mastication force was applied, and the maximum stress of the condyle prosthesis and screw, as well as the stress and strain of the mandible were recorded. In order to simulate the actual clinical situation, a special fixture was designed to test compression performance of the condyle prosthesis prepared by the fused deposition modeling (FDM) and selective laser sintering (SLS) at the rate of 1 mm/min. Results The peak stress of the PEEK condyle prosthesis was 10.733 MPa, which was located at the back of the condyle neck. The peak stress of 5 fixing screws was 9.707 5 MPa, which appeared on the 2# and 5# screws near the trailing edge of the mandibular ascending branch. The peak stress of both the prosthesis and the screw was smaller than its yield strength. The maximum pressure of the condyle prosthesis prepared by FDM and SLS was (3 814.7±442.6) N and (1 193.970±260.350) N, respectively. Compared with the SLS preparation, the FDM prepared prosthesis not only had higher compression strength but also better toughness. Conclusions The 3D printed personalized PEEK condyle prosthesis shows uniform stress distributions and good mechanical properties, which can provide the theoretical basis for PEEK as reconstruction material for repairing temporomandibular joint.