A loss of tooth (including wisdom tooth) equals a loss of jaw bone. Extractions also lead to bone necrosis. This is what leads to collapsed and unsymmetrical faces.
Look at a picture of an older person, for example:
This is why extractions should be avoided at all costs! Like braces, it is a retractive orthodontic treatment.
You see a lot of this in England… People in England have such lousy teeth due to their poor diet which prevents proper facial development. Then, the orthodontists across the pond go extraction-crazy with disastrous consequences.
Healthy teeth and a healthy jaw with no necrosis (I.E. no extractions) is one component to a good looking face. So you should make sure that you have good oral hygiene to maintain your tooth quality.
Maintaining Your Teeth
1) Saliva remineralizes/strengthens your teeth. Mouth breathing/dry mouth is the number one cause of tooth decay . So chew gum with xylitol often for saliva production (it will also remodel your jaw and improve your memory).
2) Brush your teeth with coconut oil then do oil pulling (swish coconut oil in your mouth for 20 minutes) every day.
3) Consume Vitamins: A,D,K, dairy (butter, cheese, milk) 
*Dr. Weston Price also noticed that the tribes with the best teeth also ate a lot of foods rich in enzymes (fermented foods). I.E. cheese, cultured butter, yogurt (get only Greek – they burn the lactic acid residue which oxidizes), or fermented grain drinks like kaffir beer.
**If you need extractions for any reason, or you already had extractions, consider a ceramic implant.