Study On Properties Of Porous Implants Based On Selective Laser Melting Technique

With the continuous innovation and development of medical field,artificial implants have become an effective method to repair bone defects.However,the elastic modulus of traditional implant by titanium and its alloy is much larger than that of bone tissue,it is easy to lead to the phenomenon of "stress shielding" and finally result in bone resorption and surgical failure.Therefore,to design implants with controllable porous structure can reduce elastic modulus and promote the osseointegration of implant,porous implant has been the main direction of planting technology.Due to the traditional manufacturing process can't fabricate the implant with complex inner structures,this paper uses the laser selective melting technique(SLM)to study the porous structures:(1)Fabricating implants with interconnected pores based on SLM,this study determine the process flow,path planning,molding direction and process parameters by Theoretical analysis and experimental methods;(2)According to the design principle of typical porous structure,designing hexahedron and honeycomb structures.From the perspective of industrialization,in order to improve the efficiency of design,parametric design platform is established based on Solidworks.(3)The mechanical properties of two typical porous structures are evaluated by FEA and experiments,and porous structure with superior mechanical properties is used to fabricate implants.(4)Dental implants market demand is huge,but the typical porous structure can't apply to fabricate dental implant,so the improved structure should be design for dental implant.In this study,new porous structure of dental implants(solid and hollow structure)are designed and used in basic research,including mechanical performance and osseointegration.The results of the study shows that selective laser melting technology for fabrication porous structure with good mechanical properties;typical hexahedron is superior than honeycomb structure in fabrication precision and mechanical properties;the elastic modulus is close to human bone tissue and the mechanical properties meet the biomechanical requirements with the porosity porous of structure is 50%~70%,designers should select the reasonable design parameters in the range of allowable value according to different requirements;the typical porous structure is not applicable to porous dental,the special porous structures are designed for dental implants,experimental results show that hollow structure can meet the requirements of mechanical properties,and has excellent osseointegration properties.