简介：3D打印作为一种新型快速成型制造技术,在个性化、复杂三维结构及难加工医疗器械的制造中,无论在成本还是交付时间上,都体现出传统技术无可比拟的优势。本文概述了3D打印医疗器械的主要应用特点和优势,重点论述了3D打印钛及钛合金医疗器械的研究动态、临床应用及病例,对其大规模广泛应用和推广前景进行了展望。

简介：Interfacedebondingbetweenprosthesesandabutmentswasthemostfrequentfailuremodeofresin-bondedfixedpartialsdentures(RBFPDs)inclinic.ThepurposeofthisstudywastoinvestigatetheeffectofaccessoryretentionformsonthebondstrengthofRBFPDs.Threetypesof3Dfiniteelementmodelswereconstructed.ThemodelofposteriormetalplateRBFPDwithspoon-shapedocclusalrestseatsservedasthecontrol.Theremainingtwotypesofmodelsbasedonthecontroladdedtheretentionformdesignofthepinholeandaxialgrooverespectively.Theaxialorbuccolingualloadof150Nwasappliedontheprosthesis,firstpremolarandfirstmolarrespectively.Themaximumprincipalstressesoftheadhesivelayerindifferentmodelswerecalculated.Undertheloadofthesamemagnitude,thestressduetothebuccolingualloadwassignificantlyhigherthanthatduetotheaxialloadintheadhesivelayer.Theproximalshoulder,occlusalrestseatswallandtheproximalmarginadjacenttotheshoulderwerethehighriskregionwheretheadhesivelayerdamagedeasily.Comparedwiththecontrolmodel,thepinandgroovemodelscouldslightlydecreasethestressintheadhesivelayeraftertheaxialloading,whilethestressintheadhesivelayerdrasticallydecreasedafterhorizontalloadingandreducedby22%and31%respectively.TheseresultsindicatethatthehorizontalocclusalforcehasamoreseriousharmtothedebondingofRBFPDs.Inaddition,theaccessoryretentionforms(e.g.pinandaxialgrooveretentionforms)candecreasethestresslevelintheadhesivelayer,whichareconducivetoincreasetheload-bearingcapacityofRBFPDs.

简介：目的评价3．0T时间飞跃法磁共振血管成像（3．0T3D-TOFMRA）对颅内动脉瘤的诊断价值。方法选择25例有颅内动脉瘤相关症状患者，其中男性14例，女性11例：年龄25-74岁，平均年龄57岁。对其3．0T3D-TOFMRA诊断为颅内动脉瘤患者的磁共振资料进行回顾性分析。并与数字减影血管造影（DSA）对照。结果3．OT3D-TOFMRA共显示28个动脉瘤，其中单发22例，3例为多发动脉瘤，起自颈内动脉系统25个；起自基底动脉系统3个；DSA检查共显示27个动脉瘤．结论3．0T3D-TOFMRA虽然对于直径≤3mm的微小动脉瘤的诊断存在一定的误诊及漏诊率．但其诊断颅内动脉瘤时能比较全面地显示动脉瘤．三维信息对临床确立治疗方案有很大帮助。3．OT3D-TOFMRA不失为高危人群或临床怀疑颅内动脉瘤患者筛查及随诊观察的有效手段。

简介：Furthermore,breast-feedingwithoutvitaminDsupplementationcouldprolongthedeficiency,whichmightleadtoariskofserioushealthproblemslaterinlife,includingtype1diabetesanddecreasedbonedensity.'Craniotabes,thesofteningofskullbones,inotherwisenormalnewbornshaslargelybeenregardedasaphysiologicalconditionwithouttheneedfor