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My 11 year old JR has a canine tooth that the vet thinks should be pulled, or a root canal. He has some type of disorder with his central nervous system, or maybe a pinched nerve in his neck, and I am concerned about anesthesia. He doesn't seem in pain from the tooth (yet!) and it has been this way (darker than the rest of his teeth) for awhile now. Has anyone had to face a similar problem?