Preliminary Design And Analysis Of A New Core Structure Dental Implant

Dental implantation is a commonly used method of oral cavity repair.Because biomechanical compatibility of dental implants has a great impact on long-term effect,researchers continued to study the mechanical properties of implants and their surrounding bone tissues.Marginal bone loss occurs after a long time use of dental implant,and the overloading at marginal bone was regarded as a main reason for this phenomenon for a long time.As a result,the design and material selection of implants were based on the principle of keeping the marginal bone tissue low stress peak.However,some studies have shown that low stress level is also not conducive to maintain bone properties.Caused by the high modulus of implant material,the low stress level in peri-implant bone tissues might lead to bone disuse atrophy,which known as stress shielding effect.Although the stress shielding effect attracts researchers’ attention gradually,most of the numerical analysis and simulation about dental implant have not considered this factor.This paper aims at analyzing stress shielding effect of dental implant by using finite element method.Mandible and tooth model were built based on CT data.Based on the stress state of model with 3 teeth,stress state of peri-implant bone was analyzed.The regional average strain energy density(RASED)was proposed to describe the stress level and stress distribution.Combied with peak value of Von Mises stress,RASED was used to analyze the effect of material parameters,implant diameter,length and thread design on stress at bone.The results are as follows:1)The implant of materials that share similar modulus to dentin would be beneficial to maintain healthy stress level in the peri-implant bone and relieve stress shielding effect effectively;2)To avoid overloading at bone,the diameter of implant should be wider than 1/3 of the buccolingual width,and the length of implant should be similar to root length;3)V-thread and small pitch could slightly increase the stress level of peri-implant bone,but the effect is not obvious.Based on the conclusions above,a new core structure dental implant that made by available clinical implant materials was designed,and it was verified by FEM that such implant could achieve a comparatively ideal use.