What the fuck was God thinking when (S)he made teeth? Seriously - you have to scrub them with a cleaning solution twice a day just to keep them from rotting. In addition, you have to force a string between each one of them, rinse your mouth out with chemicals, and go to a dentist twice a year to have them professionally cleaned, probed, and x-rayed. Otherwise, you'll get holes in the teeth that have to be filled with tiny pieces of metal. Talk about high maintenance.
On top of all this general upkeep you have to stay on top of, teeth present a number of other common challenges. First of all, when you're young you get one set of teeth, which subsequently FALL OUT and are replaced with more teeth. Those teeth come in any which way they feel like, leaving teens the world over with scraggly, crooked bones poking into their lips until they pay a different professional to glue METAL WIRES to them just to make them straight. Sometimes, the wires aren't enough and they give you RUBBER BANDS to attach to the wires for reinforcement. After the braces come off a year later, they give you an uncomfortable retainer with more metal on it that you're supposed to wear every night until it winds up in the junk drawer with your wind up novelty penis and the recorder your mom gave you in the fourth grade.
Then there's the "wisdom" teeth, which for all their wisdom seem to be good for nothing but causing pain and disrupting the other teeth we are already preoccupied with trying to tame. So you go to yet another professional to have these fuckers cut out entirely, leading to a week of dry sockets (or puss filled, depending on the mood and disposition of a particular socket).
Then you get old and all your teeth fall out anyway, at which time you have to wear a third set of entirely fake dentures.
Chemicals, metal, rubber, plastic, strings, surgery...what kind of body part requires so much manmade technology just to prevent nature from totally destroying it?
And your mouth is in a constant state of funk to boot.
Intelligent design my ass.