Originally Posted by topflightpro

You should be fine riding on it for now, but keep your eye on it.

Aluminum does not like to be dented and it will eventually crack and fail. However, it will be a slower process, and the failure is unlikely to be catastrophic.

I dented an aluminum top tube about two months ago and kept riding and racing the frame. It developed a slight crack after a few weeks and the top tube started getting a little wavy looking - that's when I retired it.

If it were a steel frame, the dent would not be an issue.