Effect of smoking cessation for 1 year on periodontal biomarkers in gingival crevicular fluid

Background and Objective: The aim of this 12 mo prospective study was to assess the effect of smoking cessation on periodontal tissue without periodontal intervention, using matrix metalloproteinase (MMP)-8, MMP-9 and interleukin (IL)-1ß in gingival crevicular fluid, and nicotine and cotinine in saliva. Material and Methods: Of the 122 male smokers enrolled in a smoking cessation clinic, 11 quitters, nine non-quitters, six oscillators and 13 non-smokers participated in all experiments done at follow-up week 2, and follow-up months 2, 4, 6 and 12. The following were measured: gingival index; dental plaque index and sites of 3.5 mm < probing depth < 5.5 mm using a WHO probe for the full mouth; amounts of MMP-8, MMP-9 and IL-1β in gingival crevicular fluid of the upper anterior teeth area using enzyme-linked immunosorbent assay; and concentrations of nicotine, cotinine and hydroxycotinine in saliva using high-performance liquid chromatography-tandem mass spectrometry. Results: No significant differences in MMP-8 and MMP-9 in gingival crevicular fluid were detected between smokers, quit-smokers, oscillators and non-smokers for 1 year. Only the amount of IL-1β showed that smokers (90.14 ± 65.32 pg/mL) had a significantly higher value compared with non-smokers (37.70 ± 40.90 pg/mL), quit-smokers (32.11 ± 40.50 pg/mL) and oscillators (11.90 ± 12.46 pg/mL) at 2 mo follow-up (p = 0.007). IL-1β had a positive correlation with nicotine (r = 0.351) and the cotinine (r = 0.376), nicotine (r = 0.492) and hydroxycotinine (r = 0.358), and hydroxycotinine (r = 0.413) levels at 2 wk and 4 and 6 mo follow-up, respectively. Conclusions: This 1-year prospective smoking cessation study without nonsurgical periodontal therapy shows IL-1β in gingival crevicular fluid could have a positive relationship with the nicotine and cotinine levels in saliva.