Hi Guest!

Yes medical billing for appliances used to treat TMD has been a bit of a challenge with some medical insurers since the S8262 discontinuation. But, as you stated, D7880 is still the most commonly accepted code for TMD appliances. And yes, the diagnosis codes for temporomandibular disorders were updated/changed as of October 1, 2016 as well.
For the Mora appliance, it would fall into the same category. If you run into a medical insurer that will not accept D7880, here are a few other codes we have seen accepted by a few insurers:

D7880 - occlusal orthotic device, by report

D7899 - unspecified TMD therapy, by report

Or, if the medical insurer says they won’t process the “D” codes (most will these days, but you will run into a few that won’t), you can try:

E1399 - Durable medical equipment, miscellaneous
21299 - Unlisted craniofacial and maxillofacial procedure
21499 - Unlisted musculoskeletal procedure, head

A narrative report explaining the treatment accompanying the claim is recommended since they are all "by report", “unlisted”, or "miscellaneous" codes.

For example, Aetna's medical policy for Temporomandibular disorders lists D7880 as an accepted HCPCS code is criteria is met: http://www.aetna.com/cpb/medical/data/1_99/0028.html

As for the adjustments - do you mean a repair to the appliance?

Hope this helps, have a great day!