5 July 2011 Date filed: 5 February 2007 Inventors: Stinson; Jonathan S. (Minneapolis, MN) Assignee: Boston Scientific Scimed, Inc. (Maple Grove, MN) Endoprostheses including metal matrix composite structures An endoprosthesis that includes a composite having a metal matrix and a plurality of stiffening particles in the matrix. The metal of the metal matrix can include titanium, niobium, tantalum, or alloys thereof. The stiffening particles can include a metal core and a thin surface layer. The thin surface layer can include oxides, carbides, nitrides, or combinations thereof.