We moved into a house where the former owner "cut out" a space in the MDF shelving in the kitchen cabinet.?

It has jagged edges and the lines are crooked. We would like to rent a tool to straighten out the edges, which is difficult since we cannot get the shelf out of the cabinet. Can anyone tell us what kind of portable power saw we can rent to do this ourselves? I read it should be a carbide tool. Thanks for your help.