Smoking

Attention, cigarette, cigar and pipe smokers.  Smoking and periodontal disease are closely linked. 

Research has shown that smokers tend to have a more severe progression of periodontal disease than non-smokers and also lose more teeth than nonsmokers do. According to  the Centers for Disease Control and Prevention, daily smokers have double the amount of tooth loss over age 65 compared to those over age 65 who have never smoked. 

Other tobacco products are also harmful to your periodontal health. Smokeless tobacco can also cause gums to recede which  increase the chances of losing the bone and fibers that hold your teeth in place.

Smokers are at a disadvantage after periodontal treatment since they do not heal as well, but the effects are fortunately reversible if smoking is curtailed before commencing treatment. 

Resource link: http://www.perio.org/consumer/smoking.htm