I'm really scared about my upcoming surgery at the dentist. He won't put me to sleep and has prescribed Ativan instead. Will this be enough?

i have two dentures that are not holding in place anymore, very unpleasant. i have to have two lower dental implants installed in a few weeks and i'm scared. it's just the way it is, i can't help it. i'm very anxious and stressed about this surgery. the dental clinic where i'm doing business doesn't offer intravenous moderate sedation. The dentist prescribed 2 ativans 0.5 mg to be taken 30 minutes before the appointment. my question is: will this prescription really help me control my anxiety and my uncontrollable fear? and if so, will the effect be sufficient and long enough for the duration of the surgery. expected 2 hours.