Chewing surface cavity. Now we can catch them earlier by using high magnification that you can see shadowing developing around a pit or stain.

By the time you get a stick in a chewing surface cavity or see it on an x-ray, the cavity is deep and has already destroyed a lot of good tooth structure and is more likely to need a crown or root canal in the future.

Having said that, a lot of patients have what are just stains in the grooves with no shadowing that are fine.

For me, unless it is obvious on a new patient like you who has never had cavities, I'm going to watch those suspicious areas for some time and see if anything changes. However, if I know there is a cavitie there, I'm taking photographs at the exam, and when I do treatment, so the patient knows they can trust me.

It isn't always that the new guy is trying to do unnecessary work. There are dentists that overlook a lot of stuff. That creates an awkward moment for sure.

I would get another opinion from someone you trust that isn't your old dentist.