A retrospective case control study to validate the association between Interleukin-1 gene variations and adult chronic periodontal disease in Chinese (Taiwan).

Inclusion Criteria:

• To be included in this study, an individual needs to be Han Chinese of 35 years of age or older at time of enrollment.

Exclusion Criteria:

• Subjects who, at time of enrollment, were pregnant or breastfeeding, or needed antibiotic prophylaxis before periodontal treatment will be excluded from this study.

All study subjects will be selected from a pre-existing patient database in Taiwan. All chronic periodontitis cases and controls will be subjects who were at least 35 years old at time of enrollment.

Classification of chronic periodontitis will be based on the extent of periodontal tissue destruction with consideration of tooth loss.