Are the stents put in for renal artery disease temporary or permanent?

Permanent. Arterial stents are meant to be permanent and are rarely ever removed. They can, however, develop restenosis or renarrowing that may require further intervention.
Permanent. The stents that are currently used for renal artery stenosis are permanent.
Permanent. While bioabsorbable stents are in the development pipeline, they are not yet commercially available. Renal artery stenting is done with permanent stents.