Osseointegration of Cylindrical Zirconia–Alumina Functionally Graded materials, Dental implant by Electrophoretic Deposition

Awham Salman,Saad Farid,Mohammed Eesa,Alaa Atiyah,Nada Al-Ghaban

doi:10.36533/zjmt.v1i1.1

Abstract

Electrophoretic deposition (EPD) technique is used to prepare zirconia–alumina composite layers based on the principle of functionally graded materials (FGM). The FGM were prepared with five layers. The outer layer was composed of pure α-alumina to promote biocompatibility while the inner layer was stabilised zirconia (3Y-TZP), to benefit from its tough properties. The intermediate layers were stepwise graded layers. The stability of the EPD suspensions was the main challenge during the preparation steps. Due to availability and low cost, alcoholic solutions of polyethylene glycol (PEG) and toluene were used to control conductivity, dielectric constant and the viscosity of the suspension. The appropriately applied potential, (ζ), for the deposition of each layer, was achieved via gradation of the applied voltage, which was to optimise the packing of each layer and avoid cracking after sintering at 1500 °C. The cylindrical-shaped green specimens were obtained via deposition on graphite electrodes. A small amount of acetic acid was added during the deposition of the final outer alumina layer to introduce porosity, via the bubbling of acetic acid, to encourage osseointegration. The sintered specimens were implanted in rabbit tibial bone. In vivo histological tests showed the successful osseointegration of the implants to the rabbit bone.

Highlights

The replacement of the tooth root with an implant into the jaw is an essential step for whole tooth replacement; the implant is capped with a ceramic or polymeric dental crown
Ethanol-dissolved polyethylene glycol (PEG) was used as a suspension solution for the first time for the deposition of zirconia– alumina functionally graded materials (FGM), utilising its long polymer chains (MW=4000) to suspend high-density powders of zirconia and alumina
PEG was previously used with Electrophoretic deposition (EPD) solutions, such as isopropanol and other materials, such as hydroxyapatite and graphene [37, 38]

Summary

Introduction

The replacement of the tooth root with an implant into the jaw is an essential step for whole tooth replacement; the implant is capped with a ceramic or polymeric dental crown. The dental implant carries various loads during mastication and needs to be examined for its mechanical properties, biocompatibility and integration with the bone. For these purposes, different materials, shapes and surface characteristics were examined to improve clinical outcomes. Surface modification of titanium alloys is usually performed to improve biocompatibility with the jawbone. This biocompatibility is limited by the generation of thin fibrous tissue that assists mechanical interlocking with the bone. The limited biocompatibility, cost and the complicated fabrication process of titanium alloys encourage the use of ceramic implants [1,2,3]

Methods

Results

Conclusion