Design of experiments (DoE) based optimization of dental implants: A review

Abstract

Dental implant is used as restoration of lost tooth caused due to accidental injuries. When dental implant gets osseointegrated, it behaves in a manner like natural teeth as it is continuously acted upon by static and dynamic loads. The forces get transmitted during osseointegration are directed toward jawbone and they induce excessive stresses which may result in implant fracture and fatigue failure. The way in which stresses get transferred to jawbone via interface determine the survivalrate of implant. Therefore, it is important to study the stress concentration at bone-implant interface. Mechanical parameters like stiffness, porosity, mechanochemical parameters and biomechanical parameters like implant length, diameter, thread shape and geometry affect it. Hence, it is essential to optimize these functional parameters to lower the stress intensity at implant-bone interface and improve implant stability. This review paper concentrates on different approaches used in optimization and design of experiments (DoE) techniques to have minimum stress level at the interface. Optimization techniques referred are topology and shape optimization and in DoE techniques Analysis of Variance method (ANOVA), Taguchi method, Sensitivity analysis method are discussed mainly. DoE based implant thread profile optimization by response surface method is an important understand stress distribution along interface. While Taguchi method along with FE analysis is recommended for design of experiments approach where multi factors need to optimize with factorial design.