Evaluation of Periodontal Inflammation and Its Association with Serum IL-6 and IL-1β Levels in Orthodontic Patients

Background: Maintaining periodontal health is essential for the stability of orthodontic treatment. Fixed orthodontic appliances can increase dental plaque accumulation, complicate oral hygiene, and consequently lead to gingival inflammation. Cytokines such as interleukin-6 (IL-6) and interleukin-1β (IL-1β) are key inflammatory mediators involved in periodontal tissue response. Objective: The aim of this study was to evaluate the asossiation between periodontal inflammation and serum levels of IL-6 and IL-1β in orthodontic patients. Methodology: This study was conducted at the Specialized Dental Center in Tikrit, Salah al-Din, between October 2024 and June 2025. A total of 90 participants aged 13–30 years were divided into four groups: control (n=30), baseline pre-treatment (n=20), post-treatment at 3 months (n=20), and post-treatment at 6 months (n=20). Blood samples were collected to measure serum IL-6 and IL-1β levels using ELISA. Gingival swabs were obtained from patients aged 13–21 years with orthodontic-related inflammation to identify bacterial pathogens through culture and microscopy. Results: A total of 52 bacterial isolates were identified. The predominant pathogens were Staphylococcus aureus (23.1%), Streptococcus sanguinis (19.2%), and Klebsiella pneumoniae (11.5%). IL-6 levels were highest at baseline (233.1 ± 102.6 pg/mL) and decreased progressively at 3 months (215.1 ± 111.2) and 6 months (148.7 ± 51.4), approaching control values (146.2 ± 58.9). Similarly, IL-1β levels declined from 255 ± 101.8 at baseline to 215.3 ± 67.09 at 3 months and 194 ± 60.91 at 6 months. Conclusion: Orthodontic treatment is associated with transient increases in inflammatory cytokines and bacterial accumulation. Over time, IL-6 and IL-1β levels decreased, indicating periodontal adaptation. These findings highlight the interaction between microbial factors and host immune response during orthodontic therapy.