I was brushing my teeth after eating lunch today, after I'm done I always check my teeth to make sure I didn't miss anything that I can obviously see. While I was looking, I noticed that the back (side nearest the tongue) of one of my bottom front teeth has an area where it is slightly discolored a very light gray color. Flossed between the teeth thinking it was food and it didn't come out, scraped the area with my fingernail and it didn't come off then either. The gray discoloration is on the back of my tooth, nearest the side close to another tooth. On closer inspection, there is also a very small gray area on the neighboring tooth. The discoloration is not on the gum line.
I tried to inspect this closer and held up a small book light to the tooth. Once under the light the gray area disappears and becomes very white, whiter than the rest of my tooth. The neighboring tooth that also has the slight grayish discoloration also turns bright white when a lite is shown on it.
I can only see the gray spot when looking at the tooth at a certain angle by changing my head position, or by moving the light around at different angles, but most angles the light held up to it makes the gray disappear into a very white color.
Oh no, same thing happened to me but on my top front teeth! Turned out it was a cavity. The dentist said "see that discolouration there?" That's the cavity rotting your tooth from the inside out. If you left this any longer the tooth would have died, turned black and you would need a root canal"
Go to the dentist NOW!
(He also told me that these are "floss cavities" caused by not flossing well enough! It was recommended that I gargle with salt water to stop that cavities infection from spreading to my gums)