Problem based learning=pbl. Basically, instead of traditional lectures, you work in groups of 8 people to work on different case problems. for example, a patient has a heart attack on your clinic chair...why and how? This answer will not be taught to you, instead you'l have to do independent research and discuss it with your group later on. this is how you will learn everything at USC. Instead of lecturers or faculty members, you'l have facilitators that will guide you through the material. Although USC is 100% PBL, they do have info sessions, which is the lecture counterpart of lectures (A review once every 2 weeks or so). Although, PBL is a different approach to learning dentistry, USC does well on the NBDE 1 and has a decent specialization rate. Also, the facilities are sweet. I think my only deter would be the price tag. If you get an interview, you should check out the school. gl.
