When you are in the chair at the dentist, where do you look?

I mean I don’t feel right looking up into the face of the hygienist or dentist while they are working on me. I would like to close my eyes but then I don’t know when to open my mouth and that light is extremely intense so I end up counting the holes in the ceiling tile. How about you? What do you do? Is there a proper etiquette for this? And if you are on the opposite side of this encounter, what do you prefer?