Facial changes with positional plagiocephaly. Will they correct with a helmet?

Sorry I don't have an answer, but my daughter is also just about 5 months old and was diagnosed with Torticollis/Plagiocephaly. I had heard some babies need helmets, but so far the physical therapist is saying she doesn't think she'll need one. I was concerned because I want to make sure my daughter's head, face and ear correct itself and she said with time, it will as the Torticollis is resolved. So I presume if they say it can be resolved without a helmet (if it's not too severe), then I presume with a helmet, it should also resolve itself.