Interleukin-1β and thiobarbituric acid reactive substance (TBARS) levels after phase I periodontal therapy in patients with chronic periodontitis

Background: Interleukin-1 beta (IL-1 beta), a potent stimulator of bone resorption, has been implicated in the pathogenesis of periodontal tissue destruction. There is also a clearly defined and substantial role for free radicals or reactive oxygen species in periodontal destruction. The thiobarbituric acid reactive substances (TBARS) is a commonly applied test to measure free radical activity. The aims of this study were to investigate the amount of crevicular IL-1 beta, tissue TBARS levels, and the clinical status of patients with advanced chronic periodontitis and the effect of phase I periodontal therapy on these clinical parameters and measurements. Methods: Twenty-five chronic periodontitis and 25 healthy control (C) patients were selected for the study. Plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL) were recorded from each sampling area. Gingival crevicular fluid (GCF) sampling and clinical index scores were recorded at the initial examination (IE) and 6 weeks after phase I periodontal therapy (APT). Assays for GCF IL-1 beta were carried out by enzyme-linked immunosorbent assay (ELISA). Gingival tissue samples were obtained from sites requiring periodontal flap surgery due to unresolved pockets to determine the tissue TBARS levels. The paired-samples t test was used to compare the IL-1 beta levels and clinical parameters between IE and APT. The independent-samples t test was used to determine the significance of all parameters between IE and C, and between APT and C. The correlation among the IL-1 beta levels, clinical parameters, and tissue TBARS levels was analyzed using the Pearson correlation. Results: The concentration of IL-1 beta levels was not statistically different among IE, APT, and C groups, but the total amount of IL-1 beta levels was statistically different among the 3 groups. While the levels of IL-1 beta and the clinical parameters were reduced following phase I periodontal treatment, pretreatment IL-1 beta, post-treatment IL-1 beta, and TBARS levels were statistically higher in IE and APT groups than C specimens. Tissue TBARS levels in the APT group were statistically greater than controls. No correlations were noted between tissue TBARS levels and clinical parameters in the APT group. A positive statistical correlation was detected between the total IL-1 beta and TBARS levels in the APT group. Conclusion: These data suggest that the levels of crevicular IL-1 beta and gingival tissue TBARS are closely associated with periodontal status. This relationship may be valuable in treating and monitoring periodontal disease progression.