I have a small dent in an AAP TotalGrip and I decided not to use it, better safe than sorry. From what I gather, a dent in the filter can flex and compromise the structural rigidity of the can...
I would wait to see from more people who have actually had dents in filters and used them anyway... I just don't feel like taking a risk, especially when it's my girlfriend's car at hand.
I have a PureOne that I bought a couple years ago and it has a dent (small) at the edge where the horizontal and vertical areas intersect. I've been apprehensive about using it.
I might use it. OTOH, I would not put it on a car that I would not be the ONLY driver. I won't sit there and ponder the issue for 30 seconds ..or 30 minutes and wonder what's wrong if anything happened.
I have a AC Delco UPF 52 with a nice dent in the end,wasnt about to toss out a premium $9 synthetic filter,shes on my Z71 going strong as we speek!!,no problem use it!!!!
I have used dented filters. Of course, typical small block chevy filters only filter and don't have a bypass in them to potentially get knocked off kilter.
I would say it depends on the size of the dent, Mobil 1 cans are pretty strong and the filter media is not right next to the can to get knocked out of whack. Also you could have cut it open instead of just throwing it out. What was the filter number?