THE EFFECT OF MATERIAL STIFFNESS ON DENTAL IMPLANT STABILITY – A FINITE ELEMENT ANALYSIS

The perseverance of dental implant system in restoration of occlusion is highly dependent on biomechanical overloading factors such as implant macro geometries, parafunctional oral habits, and material. Different implant materials could affect the load transfer at the bone-implant interface differently which is related to stress shielding phenomenon. To date, the role of various implant materials on the surrounding tissues as well as implant stability is still debatable and unclear especially when the implant failure is of concern. Through this study, implant body with different materials or stiffnesses that are zirconia, Ti-6Al-4V, cpTi, TiZr, and PEEK were investigated via 3-D FEA. The bone tissues were modelled based on CT image datasets and subsequently be processed in SolidWorks software. All geometries were converted into finite element models and analysed in ANSYS software. The bone and implant models were assigned with anisotropic and isotropic properties, respectively. A dynamic occlusal loading of 300 N and pretension of 20 N were applied on the implant body and screw, respectively. The results showed that the less stiff implant increased the bone stress and decreased the implant body stress values compared to the stiffer implant. Moreover, the implant with lower stiffness exhibited lower bone strain and higher implant deformation than the implant with higher stiffness. Of all implant materials analysed, PEEK is observed to be the most satisfactory. However, further modifications on PEEK would be necessary to improve inherent bioactivity and osseointegration.