Abstract:In order to study difference of stress levels and stress distribution on femur after total hip replacement,the data of experiments and finite element analyses were recorded.After good agreement was obtained between surface strains from experiments and the finite element analyses,the finite element model was construeted,which provided the capability to determine the stresses on femur.The analysis results showed that total hip replacement reduced evidently the femoral stress levels,changed the stress distribution on femur,and resulted in reduction of femoral elastic modulus.The stresses of femur had relation to cervical length and cervicodiaphyseal angle of femoral implant.It was pointed out particuarly that there was the cycle mode of bone reconstructin in designing femoral implant.

Abstract:Eighteen horn attachments of canine knee menisci were tested under tensile loading until failure, in a parallel direction to the tibial plateaus,at two different rates reproducing quasi-static and dynamic conditions.Ultimate loads,stresses,strains and Young moduli were detemined and failure mode was idontified for each specimen.An average of 552 Newtons of tensile loading was withstood by the attachments.Means ultimate stress and strain were respectively of 51 MPa and 41/00.As they are higher than rupture parameters of the meniscus itself,it is normal that no attachments'failure occurs in vivo.Functionality of future meniscal prostheses requires this kind of fixation with a similar strength.Sighificantly lower ultimate stress and tendency to avulsion failure were observed at quasi-static.strain rate compared to results at dynamic rate.This shows the importance of reproducing physilolgical conditions in in vitro tests.

Abstract:Shooting the simulayory media or dog with 7.62 mm or 5.56 mm M 193 bullets,the instantaneous deformation and displacement of the blood vessels, and the gradient attenuation of the pressures inside tubes of different diameters were observed by means of high speed photography,instantaneous pressure measurement and pathomorphological examination,which prove that the blood flow disturbance do exist at the time of wounding,and that,in view of the pathological characteristics,there is a definite relationship between the distant organ injuries and the radical blood flow disturbance.

Abstract:Three group various compressive force locked method were used in this paper.We determined that compressive force inhibited femoral epiphyseal plate growth in rabbit.Exponential function was expressed relationship between compressive force and epiphyseal plate growth.Thus obtained equation.

Abstract:An experimental research on the shape of joints surface is conducted,suing the Fourier Tranform Profilometry(FTP).The errors associated with the practical application of FTP technique are analyzed and the corresponding refinements are presented.The results of the experiments on the standard flat and cylindrical surfaces respectively show that FTP technique has an accuracy of th least 0.05mm.

Abstract:Patella fracture is a common skeletal injury causing disfunction of the knee joint.Traditional nonoperative treatment with long leg splinting usually left a painful stiff knee or a nonunion fracture, Poor extension muscle power and limited range of motion are the common Sequence especialy in aged patients.Using modified anterior tension bend wiring,we have treated displaced and comminuted patella fracture in 69 patients since 1987.For preventing dislocation of Kirschner wire,we bend the hook in both the upper and lower end of the K-wire.Then rotate the hooks into the tendon of quadriceps and patella tendon,The main complication of this method was rotation of the K-wire during or after active training of the knee joint extension,When the hooks rotated towards to the subcutaneous area,it will cause painful flexion of the knee joint. We modified this procedure with pre-making a loop on the upper end of the K-wire,The tension bend wiring passed through the loop then tightened.More than two years follow-up showed no rotation of K-wire and no losening wiring was found with our new method.

Abstract:The purpose of this in vitro experiment is to explose the effect of bleaching agent and mask agent on composite resin-enamel adhesive strength by means of shear test.The result showed:(1)bleaching agent could decrease adhesion of composite resin-enamel,but it is also related to the type of bleaching agent,the concentration of hydrogen peroxide and bleaching time.(2)Good quality mask agent,such as Bayer and 3M agent had no influence on composite resin-enamel adhesion.Therefore,clinically it is practicable to use 40%carbamide peroxide(in which the concentration of hydrogen peroxide is 14%),bleached for the limit of 10 min and thoroughly sprayed with water or covered with good quality mask agent and then finished with composite resin to complete the repair process.

Abstract:The experiment was carried out with 8 normal male adult fresh cadaver lumbar spine specimens being used as functional units.The compressive,shear and torsional stiffness of the lumbar disc were measurfed.The results of measurement showed that the compressive stiffness was 1314N/mm.the shear stiffness 242.5N/mm,the torsional stiffness 6.5Nm/deg.The strength of the lumbar disc was 80.3N.Our experimental results showed that the stiffness and strength of the disc was decreased after the posterior vertebral structures or the nucleus pulposus was removed, after the posterior vertebral structures was removed,of which the torsional stiffness was reduced by 51 percent,the torsional strength was reduced by 44 percent.

Abstract:We tested the thoracic aortas of spontaneously hypertensive rats(SHR)and Wistar Kyoto Rats(WKY)about diameter,thickness,strain-stress and relatively stretch length at fragility time.According to Lagrangian meaning and straight stretch theory of Feng Yuanzhen, we discussed the strain-stross and got the experience fomula:dT/dλ=α(T+β)=αT+ E0,which was used to assess the vascula's boimechanics of SHR and WKY in hypertension and aging.It is show that not only the vesscle's relatively stretch length of WKY is more than SHR'S, but also young than old(P<0.01,P<0.05).The vasculas of SHR and aging have higher elastic modulus.Always,the elastic protein and smooth muscle play an important role at the lower strain and the collagen fiber at higher strain.It is considered that the thoracic aortas in SHR and aging having higher elastic modulus are due to the decline in elastic protein.

Abstract:Co-Cr alloy is current major material for dental operating repairs.This product containing the elements of cobalt,chromium,nickel,molybdenum,etc,melted in high vocuum,is alloy prossessing the properties of high strength and resistance to corrosion.In the process of dental clinical use,will be wantonod profusion much paarts materials.This project though the meduim of material analyzing and testing.Results to:Co-Cr alloy may reprocess,to waster matter regeneration,in order to reduce medical cost.

Abstract:Researches have been done on buffer space of buffer type conical telescopic crown retainer as well as displacement of denture support tissues and stress distribution by means of finite element analysis.The result shows that the stress value of subbasal tissues apparently surpassed that of periodontal tissues when the loadr was within 130N,However,after the loading force reaching 130N,the occlusal space between internal & external crown of retainers dissappeared.The stress value of abutment pesiodontal support tissues increased obviously and the differential value of stress between these two kind of support tissues of denture decreased.

Abstract:In order to get the data for the use of design an new type of Artificial verterbral Body(AVB),twelve fresh spinal specimens obtained from five human male cadavers(aged from 20 to 30 years)were tested in axial compression.Load-deformation curves of the specimens showed non-linear mechanical behavior,and could be divided into three regions:Creep region、elastic region and rigid region.The elastic range and the segalation height of AVB were accorded with the elastic region and creep region of the specimens respectively.

Abstract:We successfully manufactured the Traditional Chinese Medical Massage Manipulation Monitor,measured the force applied on the monitor with rolling manipulation and analyzed the locus of resultant acting point.The result indicates that four classes can be derived from the locus.For each class,we put forward some analysis and a standard for all.