A retrospective study of periodontal disease severity in smokers and non-smokers

Smoking has been associated with increased risk of periodontitis. The aim of the present study was to compare the periodontal disease severity of adult heavy smokers and never-smokers referred for assessment and treatment of chronic periodontitis.

A random sample of patients with at least 20 teeth, stratified for smoking and age (5-year blocks, 35 to 55 years), was selected from an original referral population of 1,221 subjects with chronic adult periodontitis. Adequate records for 59 never-smokers and 44 subjects who smoked at least 20 cigarettes per day were retrieved. The percentage of alveolar bone support was measured from dental panoramic radiographs with a Schei ruler at x3 magnification with the examiner unaware of the smoking status. Probing depths at six sites per tooth were obtained from the initial consultation.

There was no significant difference in age between groups. Smokers had fewer teeth (p<0.001), fewer shallow pockets (p<0.001) and more deep probing depths (p<0.001). The differences were greater in subjects 45 years of age and over. In this age group, smokers had approximately 13% more bone loss, 15% more pockets in the 4-6 mm category and 7% more pockets in the >/= 7 mm category than the never-smokers.

This study confirmed that smokers had evidence of more severe periodontal disease than never-smokers. The differences increased with age confirming an exposure-related response.