Levels of smoking and outcome measures of root coverage procedures: a systematic review and meta-analysis

This systematic review and meta-analysis was performed to investigate if there was a significant association between the number of cigarettes smoked per day and the results of root coverage procedures.

Electronic search was performed through PubMed, Web of Science, Embase, and Scopus until January 2023. Studies were included if evaluated the outcomes of periodontal plastic surgery procedures for the treatment of gingival recession in smokers. Statistical evaluation was conducted using random-effects method to analyze the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CI).

From a total of 4494 references, 15 studies were considered relevant to be included in this study. The results showed that 44.39% sites had complete root coverage (CRC) at 6 months (non-smokers: 54.06%, < 10 cigarettes/day: 48%, 10-20 cigarettes/day: 19.56%, ≥ 20 cigarettes/day: 50%). Mean root coverage at 6 months were as follows: non-smokers: 74.94% ± 16.71%, < 10 cigarettes/day: 84.20% ± 2.24%, 10-20 cigarettes/day: 75.30% ± 14.69%, ≥ 20 cigarettes/day: 68.75% ± 26.51%. A significant difference was revealed between non-smokers and individuals who smoked 10-20 cigarettes/day in terms of CRC at 6 months: OR = 0.15 (95% CI = 0.03 to 0.71; P = .017). However, no significant difference was detected comparing 10-20 and ≥ 20 cigarettes/day.

As there was not enough data available, any definitive conclusions about the connection between an increase in the amount of cigarettes consumed per day and the results of root coverage procedures could not be reached. Further research is required with comparative studies involving individuals who smoke varying numbers of cigarettes.