Ultrasound assessment of dental implant stability: Finite element analysis of wave propagation

Abstract

Dental implants are widely used in oral and maxillofacial surgery. In clinics, accurate measurements of implants biomechanical stability are of interest since they could be used to improve the surgical strategy by adapting the choice of the healing period to each patient. Experiments using 10 MHz ultrasound device show significant effects of the amount and quality of bone in contact with the implant on the ultrasonic responses measured. In this paper, we present some numerical results for studying the sensitivity of the ultrasonic response of the implant to variations of the quantity and quality of bone tissue in contact with the implant is assessed under realistic conditions. A 3D finite element model which is based on experimental measurements was developed in order to account for the evolution of the bone biomechanical properties at the implant interface. Based on the reproducibility of the measurement, the results indicate that the device should be sensitive to the effects of a healing duration of less than one week. In all cases, the amplitude of the implant response is shown to decrease when the dental implant primary and secondary stability increase, which is consistent with the experimental results. Moreover, the effect of osseointegration phenomena in a layer between bone tissue and the implant is modeled. The numerical results show that the implant ultrasonic response changes significantly when a liquid layer is located at the implant interface compared to the case of an interface fully bounded with bone tissue.