Osseointegration Improvement of Co-Cr-Mo Alloy Produced by Additive Manufacturing

Abstract

Cobalt-base alloys (Co-Cr-Mo) are widely employed in dentistry and orthopedic implants due to their biocompatibility, high mechanical strength and wear resistance. The osseointegration of implants can be improved by surface modification techniques. However, complex geometries obtained by additive manufacturing (AM) limits the efficiency of mechanical-based surface modification techniques. Therefore, plasma immersion ion implantation (PIII) is the best alternative, creating nanotopography even in complex structures. In the present study, we report the osseointegration results in three conditions of the additively manufactured Co-Cr-Mo alloy: (i) as-built, (ii) after PIII, and (iii) coated with titanium (Ti) followed by PIII. The metallic samples were designed with a solid half and a porous half to observe the bone ingrowth in different surfaces. Our results revealed that all conditions presented cortical bone formation. The titanium-coated sample exhibited the best biomechanical results, which was attributed to the higher bone ingrowth percentage with almost all medullary canals filled with neoformed bone and the pores of the implant filled and surrounded by bone ingrowth. It was concluded that the metal alloys produced for AM are biocompatible and stimulate bone neoformation, especially when the Co-28Cr-6Mo alloy with a Ti-coated surface, nanostructured and anodized by PIII is used, whose technology has been shown to increase the osseointegration capacity of this implant.

In Vivo Evaluation of Collagen and Chitosan Scaffold, Associated or Not with Stem Cells, in Bone Repair

“…Statistically, all possible comparisons showed significant differences between groups (p < 0.05). These results suggest that a stimulus is necessary for bone repair in critical man- In the present study, despite the good results observed in the grafted groups (G2, G3, G4) compared to the control group (G1), complete repair did not occur probably because a postoperative period of 6 weeks was standardized in order to determine the speed of bone formation in response to the protocol used [81,82]. Thus, it is important to observe the longterm results in research with grafting of barrier membranes in animals, because it is still unknown whether long-term mineralization occurs in the soft tissue layer formed under the membrane [3].…”

Collagen-chitosan-hydroxyapatite composite scaffolds for bone repair in ovariectomized rats

“…There were no complications that needed to be reported and no diseases or signs recommending the removal of an animal (clinical outcome) were observed 40 . In addition, our research group has experience in the method used, as demonstrated by previously published studies 11,[41][42][43] .…”

Emerging Strategies to Improve the Design and Manufacturing of Biocompatible Therapeutic Materials

“…As a result, plasma immersion ion implantation (PIII) is the most effective alternative as it creates nanotopography even in complex structures. Iatecola et al [ 7 ] investigated the osseointegration results of the three conditions of additively manufactured Co–Cr–Mo alloy: (i) as-built, (ii) after PIII, and (iii) coated with titanium (Ti) followed by PIII. The metallic samples were designed with a solid half and a porous half to observe the bone ingrowth for different surfaces.…”