If you have not heard back from the school you are not waitlisted. The general rule is if you haven’t received a rejection then your application is still pending a decision. Waitlisting for dental school only occurs after interviews, not before. I would not worry too much if you haven’t heard back from dental schools by December. It is common and completely normal for interview offers to come in later than December! Not hearing back is the best situation to be in since most schools will notify you of a rejection almost immediately. You can check your individual application statuses on the AADSAS website.