Just a little longer term perspective here. Whether or not you get caught in dental school is kind of irrelevant. Just wait until you are practicing and get reported to the state dental board for using illegal drugs. Every single state dental board has a "Dentist Well Being Committee" that is in charge of reviewing reported drug abuse, and determining if a dentist is able to keep their license or not. They can restrict or completely revoke your license. The reporting can be done anonymously by patients, office staff, colleagues, and just about anyone else that you may have pissed off that knows about your use. Also, having any kind of arrest for drug use is a great way to lose your DEA number and prescribing power. So seriously, it may be harmless fun, but the consequences can be severe, especially when you are getting into a self regulating profession. Again, dental school is the least of your worries when it comes to this kind of thing.