I see that you have had a lot of looks but no replies so I will try to help you out. Currently, I am a 3rd year perio resident. Perio is a great specialty and I would recommend it to anyone that is interested in it. Now to answer your question. Just like with dental school, some programs are easier to get into then others. However, probably the average perio resident finished in the top 25% of his or her class and got around a 90 on the NDB 1. Some of the better programs would not except you with the above stats while other "not so good" programs you would have no problem getting in. My advice to you is to do your best to give you the best options so that you will not be limited on your choices. What makes a "not so good program"? There are many reasons like bad program director, not enough patients, limited amount of procedures and experiences i.e. implants, GBR, sinus Lifts, I.V. sedations. I hope this helps. I would write more but I have a patient waiting for me.