Tissue Eng Regen Med.  2019 Feb;16(1):11-18. 10.1007/s13770-018-0168-0.

Titanium Powder Coating Using Metal 3D Printing: A Novel Coating Technology for Cobalt-Chromium Alloy Implants

• Kim SC
• Jo WL
• Kim YS
• Kwon SY
• Cho YS
• Lim YW

• KMID: 2441251
• DOI: http://doi.org/10.1007/s13770-018-0168-0

Abstract

BACKGROUND
Three-dimensional (3D) printing with a direct metal fabrication (DMF) technology has been innovatively introduced in the field of surface treatment of prostheses. The purpose of this study was to determine whether such modifications on the surface of cobalt-chromium (CoCr) alloy by titanium powder coating using DMF improves the osseointegration ability of CoCr alloy.
METHODS
We compared the in vitro and in vivo ability of cells to adhere to DMF-coated CoCr alloy with machining. Biological and morphological responses to human osteoblast cell lines were examined by measuring cell proliferation rate and observing expression of actin filament. For in vivo study, we inserted different specimens in each medulla of the distal femurs of rabbit. After 3 months, the distal femurs were harvested, and a push-out test and histomorphometric analyses were performed.
RESULTS
The cell proliferation rate and cell adhesion in the DMF group were higher compared with those in the machined group. Human osteoblast cells on the DMF-coated surface were more strongly adhered and well-proliferated compared with those on the other surface. In the in vivo test, there was a significant difference in the ultimate shear strength between the DMF and machined groups (2.49 MPa vs. 0.87 MPa, respectively, p = 0.001). In the histomorphometric analysis, there was a significant difference in the mean bone-to-implant contact percentages between the DMF and machined groups (72.3 ± 6.2% vs. 47.6 ± 6.9%, respectively, p < 0.001).
CONCLUSION
Titanium coating of CoCr alloy with 3D metal printing provides optimal surface characteristics and a good biological surface both in vitro and in vivo.

Keyword

Cobalt-chromium alloy; Direct metal fabrication; Osseointegration; Surface treatment; 3D printing

MeSH Terms

Actin Cytoskeleton
Alloys*
Cell Adhesion
Cell Line
Cell Proliferation
Femur
Humans
In Vitro Techniques
Osseointegration
Osteoblasts
Printing, Three-Dimensional*
Prostheses and Implants
Shear Strength
Titanium*
Alloys
Titanium