Galvanic Corrosion of Ti Dental Implants Coupled to CoCrMo Prosthetic Component.

Francielly M. S. Soares,Emília S. Monteiro,Maria Elisa R. Coimbra,Carlos N. Elias,Ana Isabel C. Santana,Nicholas Dunne

doi:10.1155/2021/1313343

Francielly M. S. Soares, Emília S. Monteiro + Show 4 more

Open Access

https://doi.org/10.1155/2021/1313343

Copy DOI

Abstract

Dental implant systems are composed of an implant, prosthetic components, and a crown. Since the implants are made of commercially pure Ti (cp Ti) and prosthetic components are often made of Ti and CoCrMo alloys, a galvanic couple between these two devices may lead to galvanic corrosion, ions release, and even loss of the implant. This study aimed to investigate the corrosion resistance and measure the galvanic potential between cp Ti alloys (annealed microstructured cp Ti G4 and cold-worked nanostructured cp Ti G4) and a CoCrMo alloy. The corrosion resistance has been characterized by measuring the open circuit potential, the potentiodynamic polarization, the potentiostatic polarization, and the zero-resistance current. The cp Ti has been tested before and after a surface acid treatment. The samples' surfaces have been examined by scanning electron microscopy, and their surface roughness has been measured by a 3D optical profilometer. The polarization results showed that the CoCrMo alloy showed lower corrosion resistance than cp Ti. The surface acid treatment improves dental implant corrosion resistance. The galvanic analysis showed that the cp Ti without surface treatment behaved as an anode and after the acid treatment has a cathodic behavior in relation to the CrCoMo alloy. The highest value of galvanic current was cp TiG4 acid etched in contact with CoCrMo, in pH 2 solution. The galvanic couple with the lowest current has been the nanostructured cp Ti in contact with CoCrMo alloy.

Highlights

IntroductionE abutment is attached to the dental implant by a screw that raises it from the bone surface to above the gingival surface
A dental implant system consists of three main components: implant, prosthetic component, and crown. e implant is a cylinder, conical, or hybrid-shaped inserted into the alveolar bone for replacing the dental root (Figure 1). e prosthetic component is named an abutment. e abutment is attached to the dental implant by a screw that raises it from the bone surface to above the gingival surface. e crown that replaces the visible part of the tooth can be either cemented or attached with a screw to the abutment [1]
Ti UFG was produced by severe plastic cold deformation by equal-channel angular pressing (ECAP) at room temperature to refine grain size microstructure and increase mechanical properties [2]. e CoCrMo alloy is specified by the ASTM F1537 technical standard with a nominal chemical composition of Co-28Cr-6Mo

Summary

Introduction

E abutment is attached to the dental implant by a screw that raises it from the bone surface to above the gingival surface. Pure titanium (cp Ti ASTM F67) is commonly used in dental implants due to a good combination of adequate mechanical properties with biocompatibility [2]. Favorable properties of cp Ti include adequate mechanical strength, chemical stability, good osseointegration, high strength-to-weight ratio, and corrosion resistance [3, 4]. E dental implant surface feature plays a very important role in the interaction with the proteins, glycoproteins, and cells. When cp Ti dental implants are coupled with implant prosthesis structures made with cobalt-chromium alloys, nickel-chromium-titanium, gold-palladium alloy, and titanium alloy (Ti-6Al-4V) galvanic corrosion may occur [12]

Methods

Results

Conclusion