Assessment of salivary tumor necrosis factor-alpha level in the initial stages of treatment with fixed appliances and clear aligners

Abstract

OBJECTIVES: To assess and compare the tumor necrosis factor-alpha (TNF-α) levels in saliva samples during the initial stages of orthodontic treatment with fixed orthodontic appliances (FAs) and clear aligners (CAs). MATERIALS AND METHODS: This longitudinal study comprised 40 patients (22 males, 18 females, mean age 22 ± 7 years) who were categorized into two equal-sized groups. Group A comprised 20 patients treated with FA, and Group B comprised 20 patients treated with CA. Unstimulated saliva was collected before the intiation of treatment and then collected again after the placement of the FA/CA at 24 hrs, 7th day, and on the 21st day in both groups. TNF-α levels were determined through ELISA. STATISTICAL ANALYSIS: The data were subjected to statistical analysis. For intragroup comparison of TNF-α at different time points, the Wilcoxon matched-pairs signed-rank test was used, and for intergroup comparison of FAs and CAs at different time points, the Mann–Whitney U test was used. RESULTS: TNF-α levels in the saliva increased significantly at 24 hours, followed by a decline on the 7th day and 21st day in both groups. Changes in TNF-α levels were significantly higher in the FA group than those in the CA group at different time points. CONCLUSION: This study showed that the salivary TNF-α levels increased significantly during the initial stages of FA and CA treatment at different time points. The mean salivary TNF-α level in both FA and CA groups increased significantly at 24 hours, followed by a decline on the 7th day and then on the 21st day. There was a significant difference between the FA and CA treatment, where the CAs showed a significantly low level of TNF-α in saliva at different intervals of time when compared to the FAs.