Comparative Stress Distribution of Different Implant Designs in Bone: A 3-D Finite Element Analysis

INTRODUCTION : Development of an ideal substitute for missing teeth has been a major challenge of dental practitioner for millennia. An implant is a medical device which is made from one or more biomaterials, that are intentionally placed in the body either totally or that is partially buried beneath an epithelial surface. Many factors affect load transfer at the bone implant interface such as the type of loading, material properties of the implant and prosthesis, implant geometry, surface structure, implant design quality (diameter and length) and quantity of surrounding bone, and nature of bone implant interface. Insufficient vertical and horizontal bone volume does not allow implant placement particularly in the bone atrophy distal to the mental foramen. In this instance, small-diameter implants may be used where there is not enough bone width in the alveolar ridge; however, large-diameter implants have been proposed to increase the osseo integrated implant interface. Here using a finite element analysis the stress distribution among four different implant designs were compared and the implant with the most favorable stress distribution in bone was found. AIMS AND OBJECTIVES : The aims of the study are to compare the stress distribution of various implant designs in bone using a three dimensional finite element analysis. The objective of the study is to compare stress distribution among long and short implants and also between cylindrical, tapered and hybrid implant designs. This is to determine which implant design is the most ideal one in distributing stresses in the bone so that it will enhance the stability as well as survival rate of the implant. METHODOLOGY : A three dimensional finite element model of the mandible with four different implant designs were modelled based on the measurements of a dried human edentulous mandible using modelling software ‘Solidworks’ and was analyzed for stresses produced in the bone following axial and non-axial biting loads of different magnitude using ‘ANSYS Workbench’. RESULTS : The results of the study indicated that implants with wider diameter have more favorable stress distribution in bone compared to longer implant designs and influence of implant length and taper was not as pronounced as that of implant diameter. SUMMARY AND CONCLUSION : Based on the observations in this study, it was concluded that short implants with wider diameter have more favorable stress distribution compared to other implant designs and could be considered for use with fixed restorations. However further clinical research is suggested in order to prove it as a reliable and successful treatment modality