Comparison of cotinine levels in the peri-implant sulcular fluid among cigarette and waterpipe smokers, electronic-cigarette users, and nonsmokers

Background: Assessment of cotinine levels in the peri-implant sulcular fluid (PISF) may serve as a valuable biomarker of peri-implant diseases in nicotine-product users. Purpose: The aim of the present study was to compare cotinine levels in the PISF among cigarette smokers, waterpipe users, electronic-cigarette users, and nonsmokers. Materials and Methods: Cigarette smokers, waterpipe smokers, electronic-cigarette users, and nonsmokers were included. A questionnaire was used to collect information about age, gender, duration of smoking and vaping, family history of smoking, duration of smoking/vaping, and daily frequency of smoking/vaping. Implant-related data including implant dimensions and duration of implants in function were also recorded. In all groups, peri-implant probing depth (PD), bleeding on probing (BoP), and plaque index (PI) were assessed. Using standard techniques, PISF was collected and levels of cotinine in the PISF were measured. Sample-size estimation was performed, and statistical comparisons were done using one-way analysis of variance and Bonferroni post hoc adjustment tests. P values below.05 were categorized as statistically significant. Results: One hundred two male individuals (35 cigarette smokers, 33 waterpipe smokers, 34 electronic-cigarette users, and 35 nonsmokers) were included. Scores of peri-implant PI (P <.05) and PD (P <.05) were significantly higher among cigarette smokers, waterpipe smokers, and electronic-cigarette users compared with nonsmokers. Peri-implant BoP was more often manifested in nonsmokers compared with cigarette smokers (P <.05), waterpipe smokers (P <.05), and electronic-cigarette users (P <.05). The volume of collected PISF was significantly higher among cigarette (P <.05) and waterpipe smokers (P <.05) and electronic-cigarette users (P <.05) than nonsmokers. Cotinine levels were significantly higher in the PISF of cigarette (P <.05) and waterpipe smokers (P <.05) and electronic-cigarette users (P <.05) than nonsmokers. Conclusions: Habitual use of nicotinic products enhances the expression of cotinine in the PISF. Cotinine levels in the PISF of cigarette and waterpipe smokers and electronic-cigarette users are comparable.