to be honest, u shouldn't have to change much .. i kept like 70% of my first personal statement, cuz my passion and reasons for choosing dentistry has not changed in the pass year.. i only addressed how i've become MORE passionate followed by dentistry related experiences/examples (i'm sure u have been doing dental related stuff to boost ur resume and make u look like a stronger applicant ) ..
so...u should do hte same..now go brainstorm! reading others may spark some ideas but it comes down to you to make it enjoyable to the reader and reveal your true self..interviewers are trained to see if u bull****ed ur way thru ur personal statement and if u are as genuiune as u sound in ur essay..
good luck