I have some because I slipped on a patch of ice and broke my nose and front teeth. I had to have one of my front teeth surgically removed, while the other had broken off. It was VERY noticeable when I spoke or smiled, plus it impacted how I ate. It changed the way my mouth was shaped, as well as the way my jaw would sit. I had headaches because of the misalignment.
Because Western society has some strange obsession with teeth. If you don’t have them or you have rotten ones you’re seen as being scum, poor, etc. (all things with negative connotations). If you have teeth, people think you’re clean, respectable, etc. (things with positive connotations).
I’m sure they wish they didn’t have to, but if the natural teeth are beyond repair or had to be extracted to eliminate further decay and disease, these people still need something to replace the original teeth. The more obvious reason is to be able to eat food that requires chewing. A less obvious reason is proper alignment of the mouth with the lips and jaw.
Because they’re missing their other teeth. I know a few people with false teeth. Their natural teeth either feel out, broke or decayed so much that they had to get them pulled and get false ones.
What lucbvu2007 said. I lost all my teeth due to diabetes sucking the calcium out of them. They appeared normal & healthy, but were hallow & just a shell. The dentist had no choice but to pull them. Sad day, but I am extremely grateful for a myriad of reasons for my “new” teeth. =) I can eat! I look nice. (fake or not, I cherish them!)
Because, without teeth, you’d get really sick of eating nothing but SOUP and mashed up stuff.
Also, even though they can do great implants now for permanent fake teeth, dental insurance and Medicare won’t pay for it. They will only cover for dentures. :-/
Cavities rot teeth. Over a period of decades they can get big enough to require the tooth to be extracted, which is replaced with a false tooth. Injuries or gum disease can also be causes for teeth needing to be replaced.