Don't have black teeth

Hi all,
This post is about tooth brushing... and in general, how to get your child to do important things that he or she doesn't necessarily always want to do.
My son isn't very enthusiastic about brushing his teeth. Eating chocolate, drinking orange juice and chewing gum are all not problems, but tooth brushing can sometimes be a drama.
We find he is most responsive and willing to brush his teeth when we (or I) tell him that if he doesn't brush his teeth, he will get black teeth and they will really hurt (be "Ouwwah" or "Ouchy"). He usually responds by saying, "no black teeth... be ouwwah!" and opening his mouth really wide to let us brush his teeth.
It really works well, but some of you out there may be wondering how ethical this approach is. But I think of it this way... I am not lying to him. In fact, I am telling the absolute truth... that is, if he doesn't brush his teeth, they will get cavities and hurt. I think he needs to understand that. Isn't that our motivation for brushing our teeth? Is there anybody out there who actually enjoys brushing his or her teeth and would do it voluntarily, if not doing it had no consequences?
Is this approach any worse than telling a child that Santa Claus will not come if he or she misbehaves? I find telling the child the real consequence can be a good and effective approach.
Some more examples: if you don't wear your helmet when you ride your bike, you will hurt your head if you fall down and it will really hurt. If you don't wear your hat in the sun, you will get a sunburn on your head... you need to protect your head from the sun.
Our son always wears his helmet and hat when we ask him to, because he understands why he needs to.
So many times I have seen parents tell their kids to do something, "because I said so"... and then wonder why the kids don't listen or don't do it. I think when the child understands the real reasons (i.e. not because of Santa Claus) why we are asking them to do (or not do) certain things, he or she is much more likely to listen.
So think about this the next time your child doesn't want to brush his or her teeth or wear his or her hat. Try pulling out the real consequence card before you pull out the Santa Claus card.
You might feel bad about telling them the real consequences, but in my opinion, it is not something to feel bad about... you are not lying, and if you don't tell them, they will end up finding out the consequences the hard way, when they actually do get a tooth cavity or a sunburn on their head!
Take care and happy napping,
TBD