The epitome of the awkward teen years is of course braces. Almost everyone in the world could use braces, my orthodontist assures me of this, since basically no one in the world has perfectly aligned teeth. The science of orthodontics though requires lots of applications of physics to get the job done!
I myself went through the torture of braces for the last four years, beginning with a devilish instrument called a pendulum. Now a pendulum is not anything like a pendulum in a clock that swings back and forth other than the fact that if a pendulum was in your mouth it would probably hurt just as much. Besides that point though a pendulum is very unique in its form of torture. The pendulum is secured to the back teeth which are stationary so that it can slowwwwly push the other teeth and make the correct space to perfectly align the teeth. This is directly using physics principals as a net force is applied to the teeth so they are pushed into the correct position. The power of the pendulum is found in the metal structure itself which being secured to the back teeth cannot move meaning that it is a sort of spring applying force to the teeth.
As if this torture was not enough, the pendulum is only the first of many long steps in the process of braces. The next step is the actual braces themselves.
The metal braces consist of long metal wires which are affixed to the teeth, these wires are tightened VERY much so that they too have energy to apply forces on the teeth. They are continually tightened throughout the process on every visit so that they continue to straighten and realign the teeth.
Picture from pixshark.com
The best and probably FUNNEST (sarcasm) part of braces is most definitely the rubber bands that you are forced to wear 24/7. The rubber bands basically do the same thing that the others do applying force to the teeth so that they can be made looking perfect. This time though the energy that fixes the teeth is stored a tad differently with rubber bands being stretched obviously holding the energy. The bands have to be continually changed so that the energy is kept as high as possible and the most force applied at all times. This means moving teeth and an unhappy brace wearer.
So next time you see someone with braces, say a short prayer for them that physics doesn't hurt them too much.