I've been to the Dental Hospital near Habito Mall which is near On Nut BTS.

Crowns can be made same day or next day, as they have their own onsite lab, they are glass porcelain and my dentist here on Maui admires them every time he checks my teeth. Price is decent. I haven't been to any others in Bangkok.

Last time I was there was Jan 2022.

That shuttle bus ended during the pandemic and wasn't running when I was there in 2022. The guard at the front door will order you a shared ride on her phone for maybe 20 - 30 baht. Motorbike or tuk tuk or taxi will work from On Nut BTS. I tried walking it one time and vowed never to do that again. It is walkable, it's just not a very pleasant walk.

-David