canon - Is a professional camera cleaning needed after a dirty, dusty photography adventure trip?

I recently returned from a photography adventure in Nepal. It's a very dirty, dusty country. I have a Canon 5D mk3 and a 35mm f1.4L lens. I have been inspecting my camera for damage induced by Nepal and have found that some dust/dirt has gotten into my focus ring. I believe the 35mm is dust sealed, but at the price point this camera is at, I was wondering if this sort of thing requires a professional cleaning by Canon to protect my investment? It has a tiny bit of grinding sound and feel to it, but nothing that seems to be hurting functionality of the focus mechanism at all.