Antal M, et al. - Authors investigated if systemic inflammatory conditions and cigarette smoking could act in synergy and their co-occurrence led to a much higher risk of developing severe stage periodontal disease (PD) than what the combination of their individual risks would suggest. Enrollees received a full-mouth periodontal examination to determine their periodontal status. In the control group, it was determined that smoking in history increased the odds of developing both the moderate and the severe stages of PD. However, the change was not statistically prominent. The proposition put forth was that chronic cigarette smoke possibly led to permanent changes in the periodontal tissues, causing their hypersensitivity to inflammatory challenges.