The removal of Al 2O 3 particles from grit-blasted titanium implant surfaces: Effects on biocompatibility, osseointegration and interface strength in vivo

• Published in: Acta biomaterialia Vol. 6; no. 7; pp. 2852 - 2861
• Main Authors: Rüger, Matthias, Gensior, Tobias J., Herren, Christian, Walter, Matthias von, Ocklenburg, Christina, Marx, Rudolf, Erli, Hans-Josef
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2010
• Subjects: Aluminum oxide; Arthroplasty; Grit-blasting; Osseointegration; Titanium; Osseointegration; Grit-blasting; Titanium; Arthroplasty; Aluminum oxide
• ISSN: 1742-7061; 1878-7568
• DOI: 10.1016/j.actbio.2010.01.009

For the improvement of surface roughness and mechanical interlocking with bone, titanium prostheses are grit-blasted with Al 2O 3 particles during manufacturing. Dislocated Al 2O 3 particles are a leading cause of third-body abrasive wear in the articulation of endoprosthetic implants, resulting in inflammation, pain and ultimately aseptic loosening and implant failure. In the present study, a new treatment for the removal of residual Al 2O 3 particles from grit-blasted, cementless titanium endoprosthetic devices was investigated in a rabbit model. The cleansing process reduces residual Al 2O 3 particles on titanium surfaces by up to 96%. The biocompatibility of the implants secondary to treatment was examined histologically, the bone–implant contact area was quantified histomorphometrically, and interface strength was evaluated with a biomechanical push-out test. Conventional grit-blasted implants served as control. In histological and SEM analysis, the Al 2O 3-free implant surfaces demonstrated uncompromised biocompatibility. Histomorphometrically, Al 2O 3-free implants exhibited a significantly increased bone–implant contact area ( p = 0.016) over conventional implants between both evaluation points. In push-out testing, treated Al 2O 3-free implants yielded less shear resistance than conventional implants at both evaluation points ( p = 0.018). In conclusion, the new surface treatment effectively removes Al 2O 3 from implant surfaces. The treated implants demonstrated uncompromised biocompatibility and bone apposition in vivo. Clinically, Al 2O 3-free titanium prostheses could lead to less mechanical wear of the articulating surfaces and ultimately result in less aseptic loosening and longer implant life.