White spots on tip of my teeth. What is it and what can be done?

My teeth are all uniform in color from the the root of my gums, except for my two canine teeth, since I have white spots at the end/tip of my teeth that don't seem to go away. I want to know what that is and what can be done? Veneers? Caps? I've tried whitening toothpaste, but it doesn't seem to go away.