Porous Structure Design For Dental Implants And Its Mechanical Properties Analysis

Teeth play a irreplaceable role in daily life.Tooth loss will not only affect occlusion and pronunciation,but also affect appearance.At present,the application of dental implant restoration technology is more and more common,and its material is generally titanium alloy.However,the elastic modulus of titanium alloy is much higher than the mandible,which will cause stress shielding and leads to implant failure.Regulate and control the elastic modulus of solid dental implants,alleviating the stress shielding phenomenon and maintaining the longterm effectiveness of dental implants were the research focuses of dental implants at present.In this paper,porous structure is introduced into dental implants,and the elastic modulus is changed by changing the internal unit structure of pores,which provides a new method for better balancing the strength and elastic modulus of implants.The specific research contents of this paper are as follows:(1)Using reverse reconstruction technology,a complete mandibular model is established by processing CT scanning data.Five types of porous structures were designed based on G-A theoretical model.(2)The influence of design parameters on the equivalent elastic modulus and bending stiffness of porous structures was explored by simulation analysis,and the mechanical characteristics of different structures were verified.Which provides guidance for the design and application of porous structure.(3)The porous structure was formed by the selective laser melting technology(SLM),and the real mechanical properties of the porous structure were verified by compression experiments.Microscopic observation shows that the porous structure can be accurately formed by selective laser melting technology without sharp corner cracks and other defects during the manufactured process.The compression test results of porous structures are consistent with the simulation results.Considering the molding effect,failure mode and mechanical properties,the best parameter of porous structure to meet the implantation requirements is the circular ring structure with a height of 2mm and a diameter of 0.6 mm.(4)The finite element analysis of dental implant was carried out by simulating occlusal condition.The simulate results shows that the porous dental implant enhances the stress stimulation to the surrounding bone and relieves the stress shielding phenomenon compared with the condition of solid dental implant.At the same time,the stress distribution around the porous dental implant both well uniform and have excellent deformation coordination performance.With the condition of osteoporosis,porous dental implants can also give appropriate stress stimulation to bone tissue and relieve stress shielding phenomenon.The focus of this paper is to select the porous structure suitable for dental implants and establish the implant model,so that it can effectively alleviate the stress shielding phenomenon under the condition that different bones can meet the normal chewing movement.This study provides a new idea for the design of dental implants and a certain theoretical basis for the clinical application of dental implants.