Here is to our dear friend, "Ms. Natural Consequences"! She always has our back, doesn't she?
Are you going to make him pay any of the dental bill? Maybe he needs to not have video games for a while, like until all the cavities are filled? Or maybe he needs to sell some of his games or game systems (if you are like many parents here who have a system or three per kid - just nuts in my book!) so he can help feel the other natural consequences of his actions?
Often with my kids nothing gets through (esp with Mr. BigBanker Tyler) unless there is a financial cost. Since much of life is like that I never mind adding that aspect in. Cause as adults his teeth might hurt for months until he gets the $$ to pay the dentist.