The singer had to axe a set of concerts in order to have emergency root canal surgery last week.
The star took to Twitter to let her fans know what was going on. She said: "Waiting on the endodontist to meet me and do a nighttime root canal. Life does not work on the right schedule sometimes. This is such bad timing!!!!!... Wish me luck."
The 'How Do I Live' singer was supposed to perform in New Philadelphia, Ohio on Thursday (July 26) and Carmel, Indiana the day after (July 27). However, she was unable to appear due to the painful treatment she was receiving.
Rimes posted a graphic description of her dental work on Twitter, including details such as: "I got 3 shots in the roof of my mouth & 1 INSANE shot directly into the half dead, half ALIVE nerve through the hole he drilled on the backside of my tooth."
She went on to apologise: "So sorry to my sweet fans. We'll make it up any show missed as soon as we can. I'm in bed, have been & trying to alleviate the pain."
The singer also pulled out of a performance at Ohio's Lancaster Festival on Saturday and Sunday (July 28 and 29) so that she could rest in preparation for more treatment.