Periodontal disease occurs in 10-20% of adults, and constitutes a major cause of tooth loss. About 0.5% of U.S. adolescents between the ages of 14 to 17 years old (about 70,000) have localized early onset periodontitis and 0.1% (17,000) have the more destructive form known as generalized early onset periodontitis. Both types of early onset periodontitis often lead to tooth loss before the age of 20. Extrapolation of these figures up to age 35 leads to estimates of early onset periodontitis having a major impact on the dental health of 400,000 individuals in the U.S. population. Discovery of genetic polymorphisms at the interleukin 1 alpha and 1 beta genes significantly associated with disease risk allows genetic testing to be used to predict disease prior to onset. This can be used to target clinical efforts for disease prevention to those individuals at greatest risk. The genetic test can also justify more aggressive therapeutic treatments for individuals already affected by the early onset periodontitis who, based on their genetic profile, are predicted to exhibit very rapid disease progression.