1.Influence of insertion torque on primary stability of dental implants in beagle
Hu LIU ; Shitong XU ; Jingwen DING ; Yaping SONG ; Caimei ZHANG ; Chengwei HUANG
The Journal of Practical Medicine 2014;(10):1534-1537
Objective To investigate the correlation between the insertion torque values and primary stability of dental implants using different insertion torque values ,and search for the best insertion torque values that can acquire good primary stability. Methods Six male pure beagles were selected, and the first molars and four premolars of bilateral mandibulars were extracted. Three months later, a total of 48 XIVE dental implants were inserted. All implants were divided into group A, group B, group C, and group D based on the insertion torque value (ITV): group A, 0 < ITV < 20Ncm; group B, 20 ≤ ITV < 40Ncm; group C,40Ncm ≤ ITV < 60Ncm;group D,ITV≥60Ncm The dental implant stability was measured by Resonance frequency analysis when implanrs were placed immediately. Results No complications occured.There was significant difference between group A and grop B (P=0.012), group A and grop C (P=0.037), group A and grop D (P=0.001). There are no ignificant difference among group B,group C and grop D(P>0.05). Conclusion With the limitations of the study, it was concluded the primary stability does not simply depend on the insertion torque;When the insertion torque value was no less than 20Ncm, the dental implant can acquire good primary stability.
2.RCA quality improvement practices in the administration of promet-hazine serious error
Xuelian ZHANG ; Ying HE ; Caimei ZHANG ; Xin XU
China Modern Doctor 2014;(24):119-122
Objective To offer reference that the hospital governors use RCA quality improvement method. Methods Carries on the case analysis according to the case using RCA methods of reality, such as promethazine special to the wrong medicine drug approaches pathways leading to patient consciousness change, put forward the improvement pro-posal for quality improvement. Results During the period from June 2012 to January 2014 , the hospital did not happen because the drugs special route of administration way wrong phenomenon. Conclusion Application of RCA techniques can help us find the system reasons for the incident, and then analyze the reasons, to take practical action to improve the corresponding. And share the case method, put an end to these events.
3.Effects of skin/muscle incision and retraction on spatial learning and memory in immature rats after adult-hood
Caimei XU ; Wenyao DENG ; Yanlu YING ; Xiangcai RUAN ; Bin ZHENG ; Ruimin LUO ; Manting YAO
The Journal of Practical Medicine 2017;33(21):3535-3538
Objective To investigate the effects of skin/muscle incision and retraction(SMIR)on mechanical paw withdrawal threshold and the ability of spatial learning and memory in immature rats after adulthood. Methods 27 male SD rats aged 3 weeks and weighing 60 ~ 80 g were randomly divided into 3 groups(n = 9):control group(group C),sham operation group(group Sham)and skin/muscle incision and retraction group (group SMIR). Group SMIR received operation for skin/muscle incision and retraction. Sham group received skin/muscle incision but no retraction.No surgery was operated on C group. Pain behavior was assessed by mechanical paw withdrawal threshold(MWT)to von Frey filament stimulation before and 1,3,7,12,22 and 32 days after operation.The effects of spatial learning and memory function were assessed by Morris water-maze test at 33 days after operation. Results Mechanical paw withdrawal threshold of group SMIR decreased 1 day after operation (P<0.05)and showed no significant difference before and 3,7,12,22,32 days after operation in 3 groups(P >0.05). In Morris water-maze test,compared with Sham and C group,the average escape latency in SMIR was sig-nificantly longer in the water maze navigation experiment(P < 0.01);the ratios of time and path in the quadrant of the platform were obviously lower in SMIR(P < 0.01). There was no statistical difference between sham and C group(P>0.05).Conclusion SMIR did not cause chronic pain but may cause a decrease in the ability of spatial learning and memory in immature rats.
4.Biomechanical Study on Personalized Titanium Alloy Short Femoral Prosthesis
Hongwei LIU ; Wen ZHANG ; Junfeng JIANG ; Yiping WENG ; Nanwei XU ; Yunkun ZHANG ; Caimei WANG
Journal of Medical Biomechanics 2021;36(3):E359-E364
Objective To evaluate biomechanical properties of the personalized titanium alloy short femoral prosthesis by finite element analysis. Methods Based on the validated femoral finite element model, the base of the femoral neck was simulated, and by inserting different short femoral prostheses, four total hip replacement (THR) models, namely, the SMF stem model (Model A), BE1 stem model (Model B), MINI stem model (Model C) and personalized stem model (Model D) were established, respectively. The same loads and constraints were applied to four groups of models, and the von Mises stress distribution and deformation were calculated and analyzed, so as to compare mechanical stability of each model. Results The deformation of all THR models was smaller than that of the femur model under physiological state. The deformation of Model B was close to that of Model C, and the deformation of Model A was close to that of Model D. The peak stress of Model C was higher than that of the other 3 models, reaching 9555 MPa. The overall stress trend was Model C > Model B > Model D> Model A > Model under physiological state. Conclusions The peak stress, stress distribution of personalized short femoral stem were similar to that of SMF stem, with reasonable stress distribution, small stress shielding of the proximal femur, minimum overall deformation and shear stress of the prosthesis, and its effectiveness and stability could meet the requirements of human biomechanics, which could provide references for joint surgeons and prosthesis researchers.