A prosthesis is disclosed for placement across an ostium opening from a main body lumen to a branch body lumen. The prosthesis has a radially expansible support and a bifurcation traversing portion. The radially expansible support is configured to be deployed in at least a portion of the branch body lumen. The bifurcation traversing portion has a biostable portion having a first end and a second end. The first end is located adjacent to the radially expansible support. The bifurcation traversing portion also has a biodegradable portion having a first end coupled with the second end of the biostable portion. The biodegradable portion has a second end disposed at an end of the prosthesis opposite the radially expansible support. When deployed, the bifurcation traversing portion extends from the radially expansible support across a bifurcation and into a main body lumen such that the carina is supported thereby.
