Tribocorrosion Behavior of Ti6Al4V Coated with a Bio-absorbable Polymer for Biomedical Applications

Abstract

The modification of titanium-based surfaces has been recently studied to accelerate the osseointegration process of endosseous implants. Indeed, bioabsorbable polymer veneers carrying antimicrobials or bone growth factors to the implant-bone interface could enhance such osseointegration process. The main aim of this work was to study the tribocorrosion behavior of veneering biodegradable poly(D,L-lactide) on titanium surfaces in an artificial saliva solution. Cylinders of Ti6Al4V were prepared by grit-blasting with 250-lm alumina particles followed by HF/HNO 3 etching technique to increase the roughness of the top surface. After surface modification and cleaning, the rough surface was covered with poly (D,L-lactic acid) (PDLLA) by spin-coating technique. Reciprocating sliding tests were performed against an alumina ball at a normal load of 0.5 N, a sliding frequency of 1 Hz, and linear displacement amplitude of 3 mm using a tribometer. The sliding tests associated to open-circuit potential (OCP) measurements were performed in artificial saliva solution to mimic the oral conditions for 60 min. After tribocorrosion tests, the worn surfaces were inspected by scanning electron microscopy. The results revealed a lower coefficient of friction (COF) on PDLLA than that recorded on Ti6Al4V. A protective effect of PDLLA against wear and corrosion of Ti6Al4V was noticed on the reciprocating sliding under OCP measurements for 60 min. Furthermore, a gradual degradation of PDLLA was detected, which could be useful in situ to release of therapeutic substances to be incorporated into the bioabsorbable polymer.

Effects of poly-ether-ether ketone (PEEK) veneer thickness on the reciprocating friction and wear behavior of PEEK/Ti6Al4V structures in artificial saliva

“…Nevertheless, several issues on failures or negative effects on the long term performance of titanium-based structures such as: wear on contacting surfaces, corrosion in specific environments (e.g. oral cavity containing fluorides or acid lactic), peri-implant inflammation and excessive stress on bone due to a mismatch in Young modulus between bone and implant [1][2][3][4][5][6].…”

“…In dentistry, a veneer is a layer of material placed over a tooth or prosthetic infrastructure, either to improve the aesthetics or else to protect prosthetic structures against wear and corrosion in the mouth . Recent advances have been reported on the use of soft veneers based on thermoplasticbased polymers such as polytetrafluoroethylene (PTFE), biodegradable poly (D,L-Lactide) PDLLA and poly-ether-ether-ketone [2,4,[16][17][18]. It has been already proved that PEEK and its composites have higher wear and chemical resistance associated with a high biocompatibility when compared to titanium or stainless steel [4,[19][20][21][22][23][24][25].…”

Histological Change in Soft Tissue Surrounding Titanium Plates after Jaw Surgery

“…Metal debris may be released into the tissues as a result of manufacturing defects, corrosion, surface contamination, or mechanical damage which may occur during insertion or removal, or may be due to wear whilst in situ [5,25]. Tissue trauma, hematoma, tissue healing, and mechanical instability between the implant and the surrounding tissues may be at least partly responsible for the histological changes seen in the tissues [1].…”

“…Commercially pure titanium (CpTi) and its alloys are the first-choice material for bone internal fixation in trauma or orthognathic surgery due to their biological and mechanical properties, including their excellent biocompatibility, corrosion resistance, and high mechanical strength [1]. Even if they are well-tolerated, the long-term side effects within human tissues are still unclear and controversial [2].…”

Tribocorrosion behavior and mechanism of micro‐arc oxidation Ca/P coating on nanocrystallized magnesium alloys

“…Therefore, the tribocorrosion of the implant has attracted many attentions. Souza et al studied the tribocorrosion behavior of veneering biodegradable poly ( d , l ‐lactic acid) on Ti6Al4V surfaces by reciprocating sliding tests in an artificial saliva solution. Marques et al investigated the wear/corrosion synergistic effect on the MAO‐treated commercially pure titanium surfaces under a simulated oral environment.…”