Dose- and time-dependent association of smoking and its cessation with risk of peri-implant diseases.

DESIGN: A retrospective cohort study involved patients who received at least one implant-supported restoration at a university dental clinic between 2001 and 2013. Patients were randomly selected from an electronic database, and their recruitment via telephone contact spanned from February 2021 until July 2021.

MAIN OBJECTIVE: To investigate the association of smoking and its cessation with the risk of peri-implant mucositis and peri-implantitis in a cohort of implant-treated patients.

METHODS: The study adhered to the principles outlined in the Declaration of Helsinki and followed the STROBE guidelines for reporting observational research. Included were adult patients who were rehabilitated with dental implants, irrespective of the type of edentulism, superstructure, and prosthetic retention, provided that they had adequate access for peri-implant probing. Patients with incomplete records were excluded. Clinical measurements included plaque and bleeding indices, periodontal pocket depth, suppuration on probing, mucosal recession, and width of keratinized mucosa. Periapical radiographs were taken and marginal bone level (MBL) was measured using ImageJ software. The primary outcome variable was peri-implant status which was classified into: health (H), peri-implant mucositis (PM), and peri-implantitis (PI). Smoking status was categorized into: never-smokers, former smokers, and current smokers. Smoking information included: daily cigarette consumption, duration of smoking (in years), and age at initiation, and for former smokers, the duration of smoking cessation.

RESULTS: The cohort included 117 patients (55 females and 62 males) with a mean age of 64.2 years at examination. They were rehabilitated by 450 implants, with an average of 4.6 implants per patient and a mean duration of 8 years in function. Out of the total, 39 patients were H, while 41 and 37 showed PM and PI, respectively. Periodontal and MBL measures were significantly higher in PM and PI groups compared to H group (p < 0.001). Considering tobacco use, 56 patients were never-smokers, 42 former smokers, and 19 current smokers. The average daily consumption of cigarettes was 15.7. Ever-smokers >23 pack-years had a significantly higher risk for PI (OR = 3.40; 95% CI 0.91-17.30; p = 0.002) compared to nonsmokers. Regression analysis showed that subjects with a span since smoking cessation of more than 21 years exhibited a significantly lower risk of peri-implant diseases (PIDs) than those who had ceased smoking within 21 years (p = 0.028).

CONCLUSION: A smoking intensity exceeding 23 pack-years was significantly associated with PI risk, while the risk of PIDs was comparable between never-smokers and those who had quit smoking more than 21 years ago.