There's a couple websites out there that have some basic guidelines to what types of things you should include. Just conduct a search o google. You want your personal statement to catch the admissions committees attention (I mean c'mon they read 1000s of these things !!) you should include why you want to be a dentist, interesting experiences that may have led you to be interested in this career field, skills you have obtained, what you have done to prepare, and basically anything interesting about yourself! The possibilities are endless and your personal statement is a make or break in acceptance in some cases so I have heard. Once you are done I highly suggest getting one of your professors or advisors to look over it for you. No matter how great you are at English there could still be some mistakes and you definitely don't want any of those when trying to get accepted into a dental program! Good luck!