Effect of cigarette smoking on oral elastase activity in adult periodontitis patients

Background: We have previously reported that elastase activity in oral flui ds is significantly increased in most adult periodontitis patients. In some patients, however, elastase levels remain low despite the presence of deep periodontal pockets. In this study we explored whether or not smoking is r elated to the unexpected low elastase values in these patients. Methods: We determined what proportion of the periodontitis patients that s howed low oral elastase values were smokers. Paraffin-stimulated saliva or oral rinse samples (3 ml of water, 30 second rinse) were assayed for elasta se activity by incubating with 1 mM succinyl-alanyl-alanyl-valine-p-nitroan ilide for 20 hours at 37 degrees C, and the color formation read with a spe ctrophotometer. Neutrophil numbers were analyzed by staining the cells in t he oral rinse smear samples. Results: In 2 patient groups, one in Helsinki, Finland (n = 46) and the oth er in Vancouver, British Columbia (n = 25), 63% and 83%, respectively, of t he adult periodontitis patients who had one or more pockets greater than or equal to 6 mm and had low oral elastase values (increase of optical densit y <0.5) were smokers. Non-smoking periodontitis patients had elevated neutr ophil numbers compared to healthy subjects, while the smoking patients show ed no significant change. Next we analyzed elastase levels in stimulated wh ole saliva in a group of smokers (n = 300) and those who had quit smoking ( n = 102). Smokers had significantly lower oral elastase levels than former smokers in both advanced and moderate periodontitis groups. In this subject group, 56% of all smokers with periodontitis (at least one pocket greater than or equal to 6 mm) had oral elastase values less than 0.5 U while only 31% of those patients who had quit smoking had low values. Conclusions: Cigarette smoking leads to lowered elastase and neutrophil lev els in the oral cavity. The oral neutrophil elastase assay, therefore, cann ot be used to measure the periodontal status of smokers.