My mom has tetracycline stains
My mom takes very good care of her teeth. However she has tetracycline stains that made her not want to smile much and she is embarrass about her teeth since they look grayish yellow. She is upset because it looks like she has dirty teeth when she never had a cavity in her in any of her adult teeth. I know this problem bothers her but since her dentist told her whiting treatment would not help her very much she thinks there is nothing that can be done. Is that the case? Why can her dentist just whiten her teeth?