Has anyone successfully obtained a soft power application using dental invisaligns in Chiang Mai?

Apply in your homecountry, and wait for free in your home, not weeks in a 3 country paying hotel and food, in a country that you have no interest in visiting.

Furthermore the Embassy staff in the homecountry would know how the “standard” documents are formated, resulting in less danger of additional documentation.

Dental was fine last year but lately there have been a lot of issues with that. If you can prove you have already been using thai dentists and that you need a long term treatment that could still work. If you just apply with something like u mentioned above, it's really likely that your application will get rejected cuz it won't take over 6 months to do that. You can likely do that treatment visa exempt or with a METV

Got approved with dental plan but I have a very in-depth plan