From ADEA guidelines :
"Earliest Notification Date. Dental schools begin notifying applicants, either orally or in writing, of provisional or final acceptance no earlier than December 1 of the academic year prior to the academic year of matriculation. For example, offers of acceptance for fall 2012 begin no earlier than December 1,2011."
It doesn't say anything about rejecting before Dec 1st post interview, so how comes everyone says that they won't send rejections before Dec 1st? Is it like an unwritten rule or sth?