Hi there and first - how old are you? Why are you thinking about this?
I was in a car accident when I was 15 yrs. old and had perfect teeth (had braces as well) - they were straight, white ....beautiful. Then since I had traumatized my jaw in the car accident - after about 6 yrs. I had to have a root canal. When you have that done it discolors the tooth or causes it to turn a slightly gray color because it's dead basically - no blood or oxygen going to it.
To make a long story short - over time - I kept popping up with root canals that needed to be done (when you hurt your teeth/jaw - they say that normally happens if it's a hard hit) so I decided to get veneers on my teeth (just the upper). He did do a good job but I felt very different and somewhat regretted it because it didn't feel like me REAL teeth and food would get caught in certain spots, etc... Or someone might mention false teeth or something and I felt awkward or embarrassed.
It all boils down to ..........do you really care if it's fake or not? Nowadays everyone is getting it done so it's not a big deal, but they can also cause receeding gums as well so you have to be careful and it all depends if you're affecting it at the root or not.
It is also VERY expensive if you're going to have it done right. I'm getting 8 teeth on my top redone with crowns vs. veneers (when it's veneers - they actually shave down the outside of your real tooth so once it's done - you'll never get back your original teeth again) and it'll cost me around $11K or more. Yes it's that expensive! It all depends on what you want done but there are places that give free consultations if you're that interested.
If you're young and there's nothing wrong with your smile - just get the brightwhite ($600 to $800 depending on where you live) and it'll whiten you up. It's done in the doctor's office and you sit under rays for about 2 hours.