Evaluation of Changes in Microbiology and Periodontal Parameters During and After Fixed Orthodontic Appliances

The objective of the study was to evaluate the changes in microbiology through quantitative analysis of aerobic and anaerobic colonies and periodontal measurements during and after 1 month of removal of fixed orthodontic appliances. This prospective study comprised 30 patients, aged 12-30 years seeking orthodontic treatment in the department of Orthodontics and Dentofacial Orthopaedics of People's College of Dental Sciences and Research Centre, Bhopal from May 2016 to November 2017. Microbiological samples (supra- and subgingival plaque) and periodontal measurements like bleeding on probing (BOP), periodontal pocket depth (PPD) with oral hygiene assessment indices {plaque index (PI), gingival index (GI)} were used at 2 time interval: when patient undergoing orthodontic treatment >12 month (baseline, T₁) and 1 month after the removal of appliance (T₂). Bacterial culture method used to detect aerobic and anaerobic colony forming units (CFU) and their ratio (aerobic/anaerobic). Data analyzed using paired t-test and chi-square test. There was a significant decrease in an aerobic and anaerobic CFU (both supra- and subgingivally) and increase in CFU ratio (relatively less anaerobes) (p≤0.05) at T₂. Supragingival plaque sampling showed greater diminution in the CFU count as compared to the subgingival CFU, as these sites are more accessible for maintaining hygiene. Also, periodontal measurements showed significant decrement (PI, GI, PPD and BOP) at T₂ (p≤0.05). Fixed orthodontic treatment has transient effect on periodontium as supra- and subgingival CFU count decreases and periodontal health was ameliorated after removal of appliances which was accompanied with periodontopathic bacteria and clinical periodontal signs of inflammation during treatment.