I need to go to a dentist, "Orthodontics" is derived from the Greek "orthos" ("correct", "straight") 
Oh ok like to straighten teeth?
Exactly, in fact it has a history over 2000 years old
I had no idea it went that far back what else can you tell me?
Well it has origins as a part of medicine
Oh ok so just like Dr.'s
Yup! In fact I have heard archaeologists have discovered mummified ancients with metal bands wrapped around individual teeth