The singer's lawsuit said McKay's treatment led to "severe tooth pain, gum inflammation and chronic gum bleeding," E! News said.
Rimes said she had to subsequently undergo nine root canals, bone grafting, physical therapy and installation of a temporary bridge as a result of his treatment. She said she suffered a "permanent cosmetic deficiency" and her "ability to perform as an artist has been and will continue to be significantly compromised until all re-treatment is completed," E! quoted the lawsuit as saying.
McKay has not publicly responded to the complaint.