Just have a list of your medications and hand it to them.

The dentist needs to know because damn near all of then cause dry mouth and cavities are quick to follow the Dentist can advise you what toothpaste and mouthwash to use ( usually Biotine which is wonderful)...

No one really is going to care if your on psych meds to be honest. Most dental tech's dont even know what a psych med is anyway.