I see that Scaling and Root Planing costs about 3,000 baht in Bangkok or Pattaya. The cheapest I've seen in Ubon is 250 baht per tooth X 32 = 8,000 baht.

Any one know a competent periodontist in Ubon?

I believe the Rajavej Hospital in Ubon have a Periodontist. Works about 3 days aweek. Not sure on the cost though.