Guardian Dental Insurance has now joined Delta Dental in providing claims advancement for dental offices to help with financial assistance.  Basically, they will prepay for work based on what you did in claims with them in 2019. 

https://www.prnewswire.com/news-releases/guardian-opens-program-to-advance-claims-payments-to-dentists-301050522.html

Here is a tracker from the ADA of details of each program, including all the Deltas:

https://mailview.bulletinhealthcare.com/mailview.aspx?m=2020050501ada&r=6944831-8391&l=02e-530&t=c