I had to reapply and I changed my statement. Obviously there is something that needs improving in your over all application and though it might not be your personal statement, it never hurts to change it.
In my opinion, you are the same person, and your experiences are going to be the same as they were in the previous cycle (hopefully you did something over the year to make yourself a stronger applicant however)... so how do you change the personal statement?
Well one way is the think of other ways to say it. I changed my opening, and really developed what I learned from my experiences through out my education and dental shadowing.
For brain storming ideas: Take a look at your experiences- Describe what you did, what you learned from it, and how that knowledge will help you become a better student/dentist.
I wouldn't dwell on the fact that you are a reapplicant. I would state it (because they already know) but also explain why being a reapplicant makes you more suited than the next person. Show commitment and perseverance.
Good Luck!