This study was aimed at investigating the effects of the transfer of metallic debris during an in vitro wear test on ceramic femoral heads articulating against metallic acetabular cups. In particular, Biolox (R) Delta ceramic femoral heads of two different diameters (32 and 36 mm, three samples of each set) were run for five million cycles onto a hip wear simulator using bovine calf serum as lubricant. Wear and degradation of Biolox (R) Delta Composite femoral heads were evaluated by a gravimetric method and by micro-Raman spectroscopy, which was used to investigate possible phase changes upon the particles deposit, by assessing the monoclinic zirconia content and quantifying the tetragonal -> monoclinic zirconia transformation. Our results showed that after five million cycles, the 32 mm-acetabular cups lost a mass higher than the 36 mm-ones. Metal transfer was observed on all the Biolox (R) Delta ceramic femoral heads and determined a worsening of all roughness parameters. The micro-Raman analyses of the in vitro tested femoral heads confirmed the results previously obtained on retrievals, i.e. the stress related to metal transfer appeared to be a particularly severe condition able to induce the tetragonal -> monoclinic zirconia phase transformation. The extent of the transformation appeared higher than that observed in vivo for Biolox (R) Delta-on-Biolox (R) Delta couplings. On average, the 36 mm-femoral heads seemed more detrimentally affected by metal transfer than the 32 mm-ones; one femoral head belonging to the first set of samples underwent the highest extent of phase transformation and the highest depth involved, which in the worn centre area appeared on average higher for the 36 mm-components than for the 32 mm-ones. (C) 2016 Elsevier Ltd. All rights reserved.

Transfer of metallic debris after in vitro ceramic-on-metal simulation: Wear and degradation in Biolox Delta composite femoral heads / Taddei, Paola; Ruggiero, Alessandro; Pavoni, Eleonora; Affatato, Saverio. - In: COMPOSITES. PART B, ENGINEERING. - ISSN 1359-8368. - 115:(2017), pp. 477-487. [10.1016/j.compositesb.2016.07.008]

Transfer of metallic debris after in vitro ceramic-on-metal simulation: Wear and degradation in Biolox Delta composite femoral heads

Eleonora Pavoni
Investigation
;
2017-01-01

Abstract

This study was aimed at investigating the effects of the transfer of metallic debris during an in vitro wear test on ceramic femoral heads articulating against metallic acetabular cups. In particular, Biolox (R) Delta ceramic femoral heads of two different diameters (32 and 36 mm, three samples of each set) were run for five million cycles onto a hip wear simulator using bovine calf serum as lubricant. Wear and degradation of Biolox (R) Delta Composite femoral heads were evaluated by a gravimetric method and by micro-Raman spectroscopy, which was used to investigate possible phase changes upon the particles deposit, by assessing the monoclinic zirconia content and quantifying the tetragonal -> monoclinic zirconia transformation. Our results showed that after five million cycles, the 32 mm-acetabular cups lost a mass higher than the 36 mm-ones. Metal transfer was observed on all the Biolox (R) Delta ceramic femoral heads and determined a worsening of all roughness parameters. The micro-Raman analyses of the in vitro tested femoral heads confirmed the results previously obtained on retrievals, i.e. the stress related to metal transfer appeared to be a particularly severe condition able to induce the tetragonal -> monoclinic zirconia phase transformation. The extent of the transformation appeared higher than that observed in vivo for Biolox (R) Delta-on-Biolox (R) Delta couplings. On average, the 36 mm-femoral heads seemed more detrimentally affected by metal transfer than the 32 mm-ones; one femoral head belonging to the first set of samples underwent the highest extent of phase transformation and the highest depth involved, which in the worn centre area appeared on average higher for the 36 mm-components than for the 32 mm-ones. (C) 2016 Elsevier Ltd. All rights reserved.
2017
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11566/315648
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 10
  • ???jsp.display-item.citation.isi??? 7
social impact