Use rescue remedy spray to calm your nerves before you go in. Also, I used to work as a dental nurse until recently and I can recommend calling the dental practice up and making them aware of your distress regarding dental work/dentist, it will go into your notes and the dentist will be made aware too. They will be accommodating and be more cautious!
I’ve seen many of people come in so nervous they’ve passed out, so it’s not uncommon for them to see it, so don’t be ashamed! Maybe take a friend or relative in with you for reassurance?
As for your teeth, they have seen it ALL, they want to help you keep your teeth as long as possible in your lifetime so they may be forward with the comments about them, but it’s for a very good reason!
I remember once a gentleman had stumps for teeth, he never cleaned his teeth, ate far too much sugar and smoked profusely from a young age. He had to have them all ripped out and have dentures. He was only 45!
However, the whole time, the dentist I worked with was lovely about it, he wasn’t judgemental at any time, he was very professional!
I hope for your sake that you have a nice dentist for your visit cause it is a horrible experience for some people and you want it to be as comfortable as possible because looking after your teeth is so important!
Fingers crossed everything will be ok for you