Investigation of the hypoxia induced factor (HİF) signal pathwayassociated with daily smoking amounts in periodontal healthyindividuals

Objective: It was aimed to investigate whether the hypoxic environment caused by the amount of cigarettes smoked daily in periodontal healthy individuals affects the amount and content of signal pathway biomarkers and periodontopathogen bacteria that can be induced by hypoxia. Method: This study was conducted on 100 individuals in 5 groups as Control Group (n = 20): Individuals who do not smoke and have never smoked during their lifetime, Group 1 (n = 20): Individuals who consumed 5 or fewer cigarettes daily Group 2 (n = 20): Individuals who consumed 6 -10 cigarettes daily, Group 3 (n = 20): Individuals who consumed 11-19 cigarettes daily, and Group 4 (n = 20): Individuals who consumed 20 or more cigarettes daily. Periodontal clinical parameters were measured from all existing teeth of the patients and gingival crevicular fluid (GCF) was taken from the right maxilla teeth 16, if they were not present in the oral cavity, from teeth 15 or 17. For the determination of bacterial presence, subgingival plaque samples were collected from the gingival sulcus for each individual with paper strips 2 times. Gingival samples were collected from subjects with an indication for gingivectomy or a crown lengthening operation. Gingiva and dental plaque samples were analyzed by Polymerase Chain Reaction (PCR), and GCF samples by Enzyme Linked Immunosorbent Assay (ELISA) method. HIF-1α, HIF-1β, PHD-1 in GCF were examined and HIF-1α, VEGF amounts were examined in the gingiva. In subgingival dental plaque samples, A. actinomycetemcomitans, P. gingivalis, T. forsythia, T. denticola, P. intermedia, P. micros, F. nucleatum, C. recta, E. nodatum, E. corrodens and C. gingivalis / ochracea / sputigena periodontopathogens were examined. Results: There was no statistical difference between groups at age (p>0.05). When plaque indexes, gingival indexes and gingival sulcus depth evaluated, there was no statistically significant difference between groups (p>0.05). The number of cigarettes is statistically different among all groups (p<0.05). According to ELISA results, when the HIF-1α values are analyzed, it was found significantly higher than group 1, group 2 and group 4 (p<0.05). Group 5 was found significantly higher than group 1, group 2 and group 4, but significantly lower than group 3 (p<0.05). There was no statistical difference between the groups in HIF-1β value (p>0.05). Considering PHD 1 values, it was found that Group 5 was statistically higher than group 1, group 2 and group 3 (p<0.05). When the PZR results of HIF-1α were evaluated by keeping the control gene (GAPDH) constant, there was no difference among smokers and smokers showed 2 times increase compared to non-smokers. PZR results of VEGF showed an increase among smokers in the group with over 20 smokers, but there was no difference between other smoker groups. There was a 2 times increase in smokers compared to non-smokers. T. forsythia, T. denticola, P. intermedia, P. micros, F. nucleatum, C. recta, E. corrodens, C. gingivalis / ochracea / sputigena were detected in all groups. E. nodatum was not detected in the 0-5 smoker group. A. actinomycetemcomitans was not detected in the group of smokers more than 20 and P. gingivalis in the non-smoker group. Conclusion: There were no significant differences in clinical parameters between groups. Although it was hypothesed that hypoxia will increase depending on the amount of cigarettes consumed daily, it was detected in our study that hypoxia may change regardless of the amount of cigarettes consumed daily. Keywords: Cigarette, HIF-1α, HIF-1β, VEGF, PHD-1, Periodontopathogen