What is the role of lipopolysaccharide on the tribocorrosive behavior of titanium?

Autor(es)

Mathew, Mathew T. ^[1] ; Barao, Valentim A. ^{[2, 3]} ; Yuan, Judy Chia-Chun ^[3] ; Assuncao, Wirley G. ^[2] ; Sukotjo, Cortino ^[3] ; Wimmer, Markus A. ^[1]

Afiliação do(s) autor(es)

^[1] Rush Univ, Med Ctr, Sect Tribol, Dept Orthoped Surg, Chicago, IL 60612 - USA

^[2] Univ Estadual Paulista UNESP, Aracatuba Dent Sch, Dept Dent Mat & Prosthodont, BR-16015050 Sao Paulo - Brazil

^[3] Univ Illinois, Coll Dent, Dept Restorat Dent, Chicago, IL 60612 - USA

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS; v. 8, p. 71-85, APR 2012.
• Citações Web of Science: 33

Resumo

In an oral environment, titanium dental implants are exposed to a complex degradation process which is predominantly influenced by the intermittent mechanical events (mastication), continuous exposure to varying chemical solutions (saliva and food) and formation of microbiological (biofilm). Several studies have investigated the chemical corrosion and mechanical resistance of titanium; however, very few attempted to report on the effects of combined chemical, mechanical and microbiological interactions, which simulates the oral environment. A new multi-disciplinary research area, ``tribocorrosion{''} (a combined study of wear and corrosion), was used to address such issues. The tribocorrosive nature of titanium in artificial saliva (pH 6.5) with lipopolysaccharide (LPS) was investigated. ``Rventy-four titanium discs (12 mm diameter, 7 mm thickness), were divided into 8 groups (n = 3) as a function of material (commercially pure titanium (cpTi) and titanium-aluminum-vanadium (TiAlV) alloy) and LPS concentrations (0, 0.15, 15 and 150 mu g/ml). Sliding duration (2000 cycles), frequency (1.2 Hz) and load (20 N) parameters mimicked the daily mastication process. Electrochemical impedance spectroscopy was conducted before and after tribocorrosion to comprehend the changes in corrosion kinetics. Worn surfaces were examined using white-light-interferometry and scanning electron microscopy. Total weight loss and roughness values were calculated. LPS affected the tribocorrosive behavior of both titanium types. LPS statistically accelerated the ion exchange between titanium and saliva, and reduced the resistance of the titanium surface against corrosion (p < .05). Sliding events decreased the protectiveness of the titanium surface. In general, TiAlV exhibited better corrosion behavior, but both titanium types showed similar in total weight loss (p > .05). LPS significantly increased the cpTi weight loss (p = .041), and the roughness of the surface (p < .001). In summary, LPS negatively affected the corrosion/wear behavior of titanium, which may contribute to the failure of dental implants. (C) 2011 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 07/58926-5 - Análise comparativa da distribuição interna de tensões entre overdentures implanto-retidas e próteses fixas implanto-suportadas do tipo protocolo, através do método de elementos finitos tridimensional
• Beneficiário: Valentim Adelino Ricardo Barão
• Modalidade de apoio: Bolsas no Brasil - Doutorado