1.A clinical research of purging fu-organs therapy on patients with sthenia-heat of severe pneumonia
Huayao CHEN ; Tongqi WU ; Kejian WANG ; Lijun QIAO ; Mingxia SUN ; Yuandong FU ; Changquan CHEN ; Suyu SHI
Chinese Journal of Integrated Traditional and Western Medicine in Intensive and Critical Care 2013;(5):279-282
Objective To investigate the clinical efficacy of purging fu-organs traditional Chinese medicine (TCM)therapy for treatment of patients with severe pneumonia and sthenia-heat. Methods According to random number table method,71 patients with sthenia-heat of severe pneumonia were divided into a treatment group (35 cases)and a control group(36 cases). Conventional basic treatment was given to both groups,and additionally, small chengqi decoction was applied nasogastrically for the therapy in treatment group for 2 weeks. The clinical pulmonary infection score(CPIS),Marshall score,integration score of TCM syndromes and the mortalities in 28 days and 60 days were used to compare the clinical efficacy of the two groups. Results With the prolongation of treatment,the CPIS,Marshall score and integration score of syndromes in the two groups were gradually decreased. In treatment group,CPIS and Marshall scores were lower than those of control group on the 4th day ,and there were statistically significant differences(CPIS score:5.8±1.7 vs. 6.8±1.9,Marshall score:5.3±2.3 vs. 6.6±2.7,both P<0.05);the above 2 scores in treatment group were also lower than those of control group on the 7th and 14th day after treatment(7th day CPIS score:5.3±1.5 vs. 5.6±1.4,Marshall score:5.1±1.9 vs. 5.7±1.8;14th day CPIS score:3.9±1.7 vs. 4.4±2.3,Marshall score:4.2±1.9 vs. 4.9±2.5),but there were no statistically significant differences(all P>0.05). In addition,the integration scores of syndromes were significantly decreased on the 4th, 7th and 14th day in the treatment group significantly lower than those in the control group(4th day:7.6±2.3 vs. 10.6±2.7,7th day:7.4±2.5 vs. 9.2±2.1,14th day:6.1±1.9 vs. 8.3±2.4,all P<0.05). However,there were no statistically significant differences in mortality rates in 28 days and 60 days respectively between control group and treatment group(28 days:16.7% vs. 11.4%,60 days:25.0% vs. 20.3%,both P>0.05). Conclusion Purging fu-organs therapy not only can decrease the CPIS and Marshall scores of patients with sthenia-heat of severe pneumonia,but also can improve their syndromes.
2.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.
3.Effects of PEEK Anisotropy Formed by 3D Printing on Mechanical Properties of Femoral Substitutes
Siqi YAO ; Changning SUN ; Ling WANG ; Changquan SHI ; Dichen LI
Journal of Medical Biomechanics 2023;38(2):E276-E282
Objective Aiming at the problem of significant anisotropy in the three-dimensional ( 3D) printed polyether-ether-ketone ( PEEK) bone substitutes manufactured by material extrusion technology, taking the femur, the main load-bearing long bone of the lower limb, as an example, the biomechanical properties of the femoral model under different direction in the build chamber were evaluated by the combination of finite element analysis and in-vitro mechanical experiment. Methods A left femoral model was obtained by reconstruction from CT data. The stress and displacement of the 3D printed PEEK femur with different directions in the build chamber under five physiological postures in the human gait cycle were simulated by varying the orthogonal anisotropy mechanical properties. An in-vitro mechanical experiment was conducted to investigate the safety and stability of the femur through a 3D printed PEEK femur. Results When the long axis of the femur model was perpendicular to the building platform of the 3D printer, a better mechanical property was obtained, and the maximum von Mises stress was 46. 56 MPa, which was lower than the yield stress of PEEK, while the maximum displacement was larger than that of the natural femur under same loading condition. Therefore, the 3D printed PEEK femur met the strength requirement, but the stability needs to be improved. Conclusions The long axis is recommended to be perpendicular to the building platform when the material extrusion technology was used for the substitute of the load-bearing long bone, and the effect of its anisotropy on service performance of the substitute should be carefully considered when the 3D printing technology is used for load-bearing bone substitute.