From my experience, root canals and crowns are covered by dental insurance, not medical. Most dental issuances plans do not pay much towards this. An extraction is at least partially covered by medical insurance.
Talk to the insurance person at your dental office, they may know of some dental insurance options that are available for you. My dental office told me about Aetna Dental Savings Plan - not an insurance, but you get a discount on different services. I did a little research into it last year, and may consider joining it.
SCC R-Lateral tongue, T1N0M0
Age 47 at Dx, non-smoker, casual drinker, HPV-
Surgery: June 2005
RT: Feb-Apr 2006
HBOT: 45 in 2008; 30 in 2013
Recurrence/Surgeries: Jan & Apr 2010
Biopsy 2/2011: Moderate dysplasia
Surgery 4/2011: Mild dysplasia
Dental issues: 2013-2020